Şahin Arslan, N. and T. E. Martin. 2018. Reproductive biology of Grey-breasted Wood Wren (Henicorhina leucophrys): A comparative study of tropical and temperate wrens. Wilson Journal of Ornithology 131: 1-11.
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March 2019
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Zimova, M., L. S. Mills, P. M. Lukacs, and M. S. Mitchell. 2014. Snowshoe hares display limited phenotypic plasticity to mismatch in seasonal camouflage. Proceedings of the Royal Society B 281:20140029.
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March 2014
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Ton, R., and T. E. Martin. 2019. Nest Predation and Adult Mortality Relationships with Post-natal Metabolic Rates and Growth among Temperate and Tropical Songbirds. Journal of Experimental Biology 223: doi: 10.1242/jeb.226563.
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Abstract
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September 2020
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Variation in life history expression is thought to arise from selection acting through physiological mechanisms, but selection pressures may differ or even conflict between life stages. High offspring predation risk can favor fast growth rates among species that may be achieved by faster post-natal metabolic rates. Faster metabolism, on the other hand, may create costs for adults, such that species with low adult mortality rates may be expected to minimize such adult costs through slower metabolism. Thus, mortality at the two different life stages may differentially influence offspring metabolism. We tested these possibilities among 43 songbird species studied on three continents. We found that nest predation risk and adult mortality probability were indeed interactive in their association with offspring metabolic rates across species. Our results provide a rare example of ecological sources of mortality during different life stages being correlated with post-natal metabolic rate as a mechanism underlying offspring growth.
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Ton, R., and T. E. Martin. 2015. Metabolism correlates with variation in post-natal growth rate among songbirds at three latitudes . Functional Ecology doi: 10.1111/1365-2435.12548.
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November 2015
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Ton, R, and T. E. Martin. 2017. Proximate effects of temperature versus evolved intrinsic constraints for embryonic development times among temperate and tropical songbirds. Scientific Reports 7(1), 895.
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April 2017
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Tewksbury, J. J., T. E. Martin, S. J. Hejl, W. Jenkins, and M. Kuehn. 2002. Parental care of a cowbird host: caught between the costs of egg-removal and nest predation. Proceedings of the Royal Society of London 269: 423-429.
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January 2002
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Tewksbury, J. J., L. Garner, S. Garner, J. D. Lloyd, V. Saab, and T. E. Martin. 2006. Alternative hypotheses of landscape influence on nest predation and brood parasitism in fragmented ecosystems. Ecology:87(3), Pp. 759-768.
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March 2006
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Stetz, J. B., M. S. Mitchell, and K. C. Kendall. 2018. Evidence of Competition in Shaping Seasonal Density Patterns of Sympatric Ursids. Ecography. DOI: 10.1111/ecog.03556
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April 2018
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Sparklin, W. D. M. S. Mitchell, D. B. Jolley, and L. B. Hanson. 2009. Territoriality of feral pigs in a highly persecuted population on Fort Benning, Georgia Journal of Wildlife Management 73:497-502.
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October 2008
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Slevin, M. C., E. E. Bin Soudi, and T. E. Martin. 2020. Breeding Biology of Mountain Wren-Babbler (Gypsophila crassus). Wilson Journal of Ornithology 132(1):124-133.
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January 2020
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Sharp, N. W., M. S. Mitchell, and J. B. Grand. 2009. Sources, sinks, and spatial ecology of cotton mice in longleaf pine stands undergoing restoration. Journal of Mammalogy.
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December 2009
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Sells, S. N., and M. S. Mitchell. In press. The economics of territory selection. Ecological Modelling.
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October 2020
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Sells, S. N., S. B. Bassing, K. J. Barker, S. C. Forshee, A. C. Keever, J. W. Goerz, and M. S. Mitchell. 2018. Increased scientific rigor will improve reliability of research and effectiveness of management. Journal of Wildlife Management 82:485-494. DOI: 10.1002/jwmg.21413.
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March 2018
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Sells, S. N., M. S. Mitchell, and J. A. Gude. 2019. Addressing disease risk to develop a health program for bighorn sheep in Montana. Chapter 14 in: Rung, M. C., S. J. Converse, J. E. Lyons, and D. R. Smith, editors, Case Studies in Decision Analysis for Natural Resource Management, Johns Hopkins Press.
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July 2019
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Sells, S. N., M. S. Mitchell, V. L. Edwards, J. A. Gude, and N. J. Anderson. Submitted. A Decision Analytical Approach to Proactive Management of Pneumonia Epizootics in Bighorn Sheep. Journal of Wildlife Management.
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July 2016
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Sells, S. N., M. S. Mitchell, J. J. Nowak, P. M. Lukacs, N. J. Anderson, J. M. Ramsey, and J. A. Gude. Submitted. Modeling Risk of Pneumonia Epizootics in Bighorn Sheep. Journal of Wildlife Management.
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January 2015
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Sells, S. N., C. M. Costello, P. M. Lukacs, L. L. Roberts, & M. A. Vinks. 2023. Predicted connectivity pathways between grizzly bear ecosystems in Western Montana. Biological Conservation, Volume 284, 110199, ISSN 0006-3207, https://doi.org/10.1016/j.biocon.2023.110199
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Abstract
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Download
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July 2023
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Habitat and corridor mapping are key components of many conservation programs. Grizzly bear populations in the continental US are fragmented and connectivity among federal recovery areas is a conservation goal. Building on recent work, we modeled movements to predict areas of connectivity, using integrated step selection functions (iSSFs) developed from GPS-collared grizzly bears (F = 46, M = 19) in the Northern Continental Divide Ecosystem (NCDE). We applied iSSFs in a >300,000 km<sup>2</sup> area including the NCDE, Cabinet–Yaak (CYE), Bitterroot (BE), and Greater Yellowstone (GYE) Ecosystems. First, we simulated directed movements (randomized shortest paths with 3 levels of exploration) between start and end nodes across populations. Second, we simulated undirected movements from start nodes in the NCDE, CYE, or GYE (no predetermined end nodes). We summarized and binned results as iSSF classes (1 = lowest relative predicted use; 10 = highest relative predicted use) and evaluated predictions using 127 outlier grizzly bear locations. Connectivity pathways were primarily associated with mountainous areas and secondarily with river and stream courses in open valleys. Values at outlier locations indicated good model fit and mean iSSF classes at outlier locations (≥7.4) and Spearman rank correlations (≥0.87) were highest for undirected simulations and directed simulations with the highest level of exploration. Our resulting predictive maps will facilitate on-the-ground application of this research for prioritizing habitat conservation, human-bear conflict mitigation, and transportation planning. Additionally, our overall modeling approach has direct utility for myriad species and conservation applications.
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Sells SN, Costello CM (2024) Predicting future grizzly bear habitat use in the Bitterroot Ecosystem under recolonization and reintroduction scenarios. PLOS ONE 19(9): e0308043. https://doi.org/10.1371/journal.pone.0308043
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Abstract
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Download
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September 2024
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Many conservation actions must be implemented with limited data. This is especially true when planning recovery efforts for extirpated populations, such as grizzly bears (<i>Ursus arctos</i>) within the Bitterroot Ecosystem (BE), where strategies for reestablishing a resident population are being evaluated. Here, we applied individual-based movement models developed for a nearby grizzly bear population to predict habitat use in and near the BE, under scenarios of natural recolonization, reintroduction, and a combination. All simulations predicted that habitat use by grizzly bears would be higher in the northern half of the study area. Under the natural recolonization scenario, use was concentrated in Montana, but became more uniform across the northern BE in Idaho over time. Use was more concentrated in east-central Idaho under the reintroduction scenario. Assuming that natural recolonization continues even if bears are reintroduced, use remained widespread across the northern half of the BE and surrounding areas. Predicted habitat maps for the natural recolonization scenario aligned well with outlier and GPS collar data available for grizzly bears in the study area, with Spearman rank correlations of ≥0.93 and mean class values of ≥9.1 (where class 10 was the highest relative predicted use; each class 1 – 10 represented 10% of the landscape). In total, 52.4% of outlier locations and 79% of GPS collar locations were in class 10 in our predicted habitat maps for natural recolonization. Simulated grizzly bears selected habitats over a much larger landscape than the BE itself under all scenarios, including multiple-use and private lands, similar to existing populations that have expanded beyond recovery zones. This highlights the importance of recognizing and planning for the role of private lands in recovery efforts, including understanding resources needed to prevent and respond to human-grizzly bear conflict and maintain public acceptance of grizzly bears over a large landscape.
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Schwabl, H., M. G. Palacios, and T. E. Martin. 2007. Selection for rapid development leads to higher embryo exposure to maternal androgens among passerine species. American Naturalist 170: 196-206.
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August 2007
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Sarah N. Sells, Cecily M. Costello, Paul M. Lukacs, Frank T. van Manen, Mark Haroldson, Wayne Kasworm, Justin Teisberg, Milan A. Vinks, Dan Bjornlie. 2023. Grizzly bear movement models predict habitat use for nearby populations. Biological Conservation, Volume 279, 109940, ISSN 0006-3207, https://doi.org/10.1016/j.biocon.2023.109940.
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March 2023
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Saalfeld, S. T., S. S. Ditchkoff, J. J. Ozaga, and M. S. Mitchell. 2007. Seasonal variation in sex ratios provides developmental advantages in white-tailed deer, Odocoileus virginianus. Canadian Field Naturalist.
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January 2009
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S. S. Ditchkoff, B.L. Williams, M.S. Mitchell, J.B. Grand, and J.J> Millspaugh. Fecal Glucocorticoid Metabolites in Wild Pig Populations Fluctuate Based on Reproductive Cycle. Wildlife Society Bulletin: 00(0): 000-000, 201X
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Abstract
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February 2011
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Wild pigs (Sus scrofa) pose considerable ecological problems as an invasive exotic. However, our understanding of many aspects of the ecology of this species is limited. Our goal was to examine the relationships between patterns of stress and reproductive behavior in a free ranging population of wild pigs through analysis of fecal glucocorticoid metabolites. We collected fecal samples from both trapped and hunter harvested animals between August 2004 and January 2006. Sexually mature pigs on Fort Benning had two seasons of elevated stress levels corresponding with two distinct periods of increased farrowing activity (March/April and July/August). For sexually mature females, fecal glucocorticoid levels were greater during the peak farrowing seasons than during the rest of the year. Fecal glucocorticoids in sexually mature males peaked during the periods immediately preceding each breeding season, and were at their lowest point during the peak farrowing seasons. Fecal glucocorticoid concentrations did not differ among sexually immature individuals of either sex between the breeding seasons and the rest of the year. Individuals collected from traps exhibited greater fecal glucocorticoid concentrations than individuals collected via hunter harvest. Mature males likely experienced their greatest levels of stress during the peak of the breeding season due to heightened breeding activity, and decreased stress during the peak of the farrowing season due to a decrease in breeding activity as the majority of receptive females were already pregnant. The timing of peak stress levels among both sexes of sexually mature animals and the lack of fluctuations in stress levels among sexually immature animals lead us to conclude that reproduction and the timing of peak reproductive activity are the major factors influencing stress among free-ranging wild pigs. This study has established baseline parameters of stress in wild pig populations, and highlights the temporal periods during which particular classes of animals experience the greatest levels of stress.
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Ruprecht, J. S., D. E. Ausband, M. S. Mitchell, E. O. Garten, and P. Zager. 2012. Homesite attendance based on sex, breeding status, and number of helpers in gray wolf packs. Journal of Mammalogy 93:1001–1005.
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September 2012
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Runge, M.C., J.B. Grand, and M.S. Mitchell. 2013. Structured decision making. pp. 51-72. In P.R. Krausman and J.W. Cain eds. Wildlife Management and conservation: Contemporary principles and practices. Johns Hopkins Baltimore, Maryland.
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January 2013
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Runge, M.C., J.B. Grand, and M.S. Mitchell. 2013. Structured decision making. Pages 51-72 in P.R. Krausman and J.W. Cain III, editors. Wildlife Management and Conservation: Contemporary Principles and Practices. The Johns Hopkins University Press.
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November 2014
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Ruggera, R. A., and T. E. Martin. 2010. Breeding biology and natural history of the Slate-throated Whitestart in Venezuela. Wilson Journal of Ornithology 122: 447-454.
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September 2010
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Rosenblatt, E, Cook, J. D., DiRenzo, G.V., Grant, E.H.C., Arce, F., Pepin, K. M., Rudolph, J.F., Runge, M.C., Shriner, S., Walsh, D., and Mosher, B.A. 2023. Epidemiological modeling of SARS-CoV-2 in white-tailed deer (Odocoileus virginianus) reveals conditions for introduction and widespread transmission. biorxiv.
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September 2023
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Roff, D. A., V. Reme', and T. E. Martin. 2005. The evolution of fledging age in songbirds. Journal of Evolutionary Biology. 18:1425-1433.
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January 2005
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Robinson, H., T. Ruth, J. A. Gude, D. Choate, R. DeSimone, M. Hebblewhite, K. Kunkel, M. R. Matchett, M. S. Mitchell, K. Murphy, and J. Williams. 2015. Linking Resource Selection and Mortality Modeling for Population Estimation of Mountain Lions in Montana. Ecological Modelling g 312: 11–25.
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June 2015
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Robinson, H, R. DeSimone, C. Hartway, J. Gude, M. Thompson, M. Mitchell and M. Hebblewhite. Submitted. A test of the compensatory mortality hypothesis in mountain lions: a management experiment in west-central Montana. Journal of Wildlife Management
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June 2014
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Rich, L. N., M. S. Mitchell, J. A. Gude, and C. A. Sime. 2012. Anthropogenic mortality, intraspecific competition, and prey availability structure territory sizes of wolves in Montana. Journal of Mammalogy 93:722-731.
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June 2012
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Rich, L. N., E. M. Glenn, M. S. Mitchell, J. A. Gude, R. E. Russell, C. A. Sime, D. E. Ausband, and J. D. Nichols. Submitted. Estimating occupancy and predicting numbers of gray wolf packs in Montana using hunter surveys. Journal of Wildlife Management 77:1280-1289.
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July 2013
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Reynolds-Hogland, M. J., and M. S. Mitchell. 2007. Three axes of ecological studies: Matching process and time in landscape ecology. IN J. A. Bissonette and I. Storch (eds) Temporal Dimensions of Landscape Ecology: Wildlife Responses to Variable Resources. Springer, New York. 10:174-194
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January 2007
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Reynolds-Hogland, M. J., and M. S. Mitchell. 2007. Road effects on habitat quality for black bears in the Southern Appalachians:a long term study. Journal of Mammalogy, 88(4):1062-107.
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August 2007
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Reynolds-Hogland, M. J., and M. S. Mitchell. 2006. Spatio-temporal availability of soft mast in clearcuts in the Southern Appalachians. Forest Ecology and Management 237:103-114.
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December 2006
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Reynolds-Hogland, M. J., M. S. Mitchell, R. A. Powell, and D. C. Brown. 2007. Selection of den sites by black bears in the Southern Appalachians. Journal of Mammology, 88(4):1062-1073.
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August 2007
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Reynolds-Hogland, M. J., L. B. Pacifici, and M. S. Mitchell. 2007. Linking resources with demography to understand resource limitation for bears. Journal of Applied Ecology, 44:1166-1175.
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December 2007
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Reynolds-Hogland, M. J., J. S. Hogland, M. S. Mitchell. 2007. Evaluating intercepts from demograhic models to understand resource limitation and thresholds. Ecological Modeling, 211:424-432.
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November 2007
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Reynolds, M. J., and M. S. Mitchell. 2007. Three Axes of Ecological Studies: Matching Process and Time in Landscape Ecology. In Bissonette, J. A., and I. Storch, editors, Temporal Explicitness in Landscape Ecology: Wildlife Responses to Changes in Time. Springer, New York, NY.
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April 2007
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Remes, V., and T. E. Matin. 2002. Environmental influences on the evolution of growth and development rates in passerines. Evolution 56(12): 2505-2518.
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December 2002
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Prentice, M.B., M.L.J. Gilbertson, D.J. Storm, W.C. Turner, D.P. Walsh, M.E. Pinkerton, P.L Kamath. 2024. Metagenomic sequencing sheds light on microbes putatively associated with pneumonia-related fatalities of white-tailed deer (Odocoileus virginianus), Microbial Genomics, 10:001214. https://doi.org/10.1099/mgen.0.001214
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March 2024
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Powell, R. A., and M. S. Mitchell. 2012. What is a home range? Journal of Mammalogy 93:948-958.
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September 2012
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Parsons, E. W. R., J. L. Maron, and T. E. Martin. 2013. Elk herbivory alters small mammal assemblages in high elevation riparian drainages. Journal of Animal Ecology 82: 459-467.
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Abstract
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February 2013
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1. Heavy herbivory by ungulates can substantially alter habitat, but the indirect consequences of habitat modification for animal assemblages that rely on that habitat are not well studied. This is a particularly important topic given that climate change can alter plant-herbivore interactions.
2. We explored short-term responses of small mammal communities to recent exclusion of Rocky Mountain elk (Cervus elaphus) in high elevation riparian drainages in northern Arizona, where elk impacts on vegetation have increased over the past quarter century associated with climate change. We used 10 ha elk exclosures paired with unfenced control drainages to examine how browsing influenced the habitat use, relative abundance, richness, and diversity of a small mammal assemblage.
3. We found that the small mammal assemblage changed significantly after five years of elk exclusion. Relative abundance of voles (Microtus mexicanus) increased in exclosure drainages, likely due to an increase in habitat quality. The relative abundances of woodrats (Neotoma neomexicana) and two species of mice (Peromyscus maniculatus and P. boylii) decreased in the controls, while remaining stable in exclosures. The decline of mice in control drainages was likely due to the decline in shrub cover that they use. Thus, elk exclusion may have maintained or improved habitat for mice inside the exclosures while habitat quality and mouse abundance both declined outside the fences. Finally, small mammal species richness increased in the exclosures relative to the controls while species diversity showed no significant trends.
4. Together, our results show that relaxation of heavy herbivore pressure by a widespread native ungulate can lead to rapid changes in small mammal assemblages. Moreover, exclusion of large herbivores can yield rapid responses by vegetation that may enhance or maintain habitat quality for small mammal populations.
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Palacios, M. G., and T. E. Martin. 2006. Incubation period and immune function: a comparative field study among coexisting birds. Oecologia 146:505-512.
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March 2006
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Oteyza, J. C., J. C. Mouton, and T. E. Martin. 2021. Adult survival probability and body size affect parental risk-taking across latitudes. Ecology Letters 24:20-26.
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January 2021
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Nowak, J. J., Hurley, M. A., Lukacs, P. M., Walsh, D., & White, C. L. (2023). Population Monitoring. In Ecology and Management of Black-tailed and Mule Deer of North America (pp. 291-306). CRC Press. https://doi.org/10.1201/9781003354628-19
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Abstract
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April 2023
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This chapter describes the importance of population monitoring, a complex task with many interrelated parts. The theoretical foundation for monitoring lies in the random sample and the field of statistics. Effective survey design provides the building blocks for monitoring all relevant quantities in a general and reusable fashion. Population models help to formalize hypotheses, design monitoring programs, find efficient uses of resources, and make proactive assessments of management actions. By combining the guidance received from population models with strict sampling procedures, the state of the population can efficiently be established, which facilitates adoption of the scientific method and rigorous decision making.
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Niklison, A., J. I. Areta, R. A. Ruggera, K. L. Decker, C. Bosque, and T. E. Martin. 2007. Natural history and breeding biology of the Rusty-breasted Antpitta (Grallaricula ferrugineipectus). Wilson Journal of Ornithology 120: 345-352.
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June 2008
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Newby, J. R., L. S. Mills, T. K. Ruth, D. H. Pletscher, M. S. Mitchell, H. B. Quigley, K. M. Murphy, and R. DeSimone. 2013. Human-caused mortality influences spatial population dynamics:
Pumas in landscapes with varying mortality risks. Biological Conservation 159:230-239.
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April 2013
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Nalwanga, D., P. Lloyd, M. A. duPlessis, and T. E. Martin. 2004. The influence of nest site characteristics on the nesting success of Karoo Prinia. Ostrich 75: 269-274.
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September 2004
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Nalwanga, D., P. Lloyd, M. A. duPlessis, and T. E. Martin. 2004. Nest-site partitioning in a strandveld shrubland bird community. Ostrich 75: 250-258
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September 2004
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Muñoz and Martin. 2014. Breeding biology of the Spotted Barbtail (Premnoplex brunnescens). Wilson Journal of Ornithology 126: 717-727.
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December 2014
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Muir, J. A., D. Licata, and T. E. Martin. 2008. Reproductive biology of the Red-ruffed Fruitcrow (Pyroderus scutatus granadensis). Wilson Journal of Ornithology 120: 862-867.
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November 2008
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Mouton, J. C., and T. E. Martin. 2019. Nest structure affects auditory and visual detectability, but not predation risk, in a tropical songbird community. Functional Ecology 33:1973–1981.
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October 2019
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Mouton, J. C. and T. E. Martin. 2018. Fitness consequences of interspecific nesting associations among cavity nesting birds. American Naturalist 192: 389–396.
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September 2018
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Mouton J. C., B. W. Tobalske, N. A. Wright, and T. E. Martin. 2020. Compensatory plasticity offsets performance and survival costs of predation risk across life stages. Functional Ecology https://doi.org/10.1111/1365-2435.13650.
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September 2020
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Morgan Henderson, M., M. Hebblewhite, M. S. Mitchell, J. B. Stetz, K. C. Kendall, and R. G. Carlson. 2015. Modeling multi-scale resource selection for bear rub trees in Northwestern Montana and Idaho. Ursus 26:28–39
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January 2015
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Monkkonen, M., and T. E. Martin. 2000. Sensitivity of comparative analyses to population variation in trait values: clutch size and cavity excavation tendencies. Journal of Avian Biology 31: 576-580
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September 2000
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Mitchell, M. S., and R. A. Powell. 2008. Estimated home ranges can misrepresent habitat relationships on patchy landscapes. Ecological Modelling 216:409-414.
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October 2008
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Mitchell, M. S., and R. A. Powell. 2007. Optimal use of resources structures, home ranges and spatial distribution of black bears. Animal Behaviour 74:219-230.
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June 2007
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Mitchell, M. S., and R. A. Powell. 2012. Foraging optimally for a home range. Journal of Mammalogy 93:917-928.
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September 2012
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Mitchell, M. S., and M. Hebblewhite. 2012. Carnivore habitat ecology: integrating theory and application. In Boitani and Powell, editors, Carnivore ecology and conservation: a handbook of techniques. Oxford University Press, London, UK.
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January 2012
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Mitchell, M. S., S. N. Sells, S. B. Bassing, K. J. Barker, A. C. Keever, S. C. Forshee, and J. W. Goerz. 2018. Explicitly reporting tests of hypotheses improves communication of science. Journal of Wildlife Management. DOI: 10.1002/jwmg.21461.
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May 2018
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Mitchell, M. S., S. N. Sells, K. J. Barker, S. B. Bassing, A. C. Keever, S. C. Forshee, and J. W. Goerz. 2018. Testing A Priori Hypotheses Improves the Reliability of Wildlife Research. Journal of Wildlife Management. DOI: 10.1002/jwmg.21568
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August 2018
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Mitchell, M. S., S. H. Rutzmoser, T. B. Wigley, C. Loehle, J. A. Gerwin, P. D. Keyser, R. A. Lancia, R. W. Perry, C. J. Reynolds, R. E. Thill, R. Weih, D. White, Jr., P. Bohall Wood. 2006. Relationships between avian richness and landscape structure at multiple scales using multiple landscapes. Forest Ecology and Management.
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May 2006
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Mitchell, M. S., M. J. Reynolds-Hogland, M. L. Smith, P. B. Wood, J. A. Beebe, P. D. Keyser, C. Loehle, C. J. Reynolds, and D. White, Jr. 2008. Projected long-term response of Southeastern birds to forest management. Forest Ecology and Management 256(2008):1884 1896.
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October 2008
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Mitchell, M. S., L. N. Rich, and L. S. Mills. 2014. Using radiotelemetry to answer habitat and population questions. In T. Tshering and L. S. Mills, editors, Wildlife Research Techniques in Rugged Mountainous Landscapes. Ugyen Wangchuk Institute for Conservation and Environment, Bhumtang, Bhutan.
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January 2014
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Mitchell, M. S., L. B. Pacifici, J. B. Grand, and R. A. Powell. 2009. Contributions of vital rates to growth of a protected population of American black bears. Ursus 20:77-84.
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December 2009
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Mitchell, M. S., J. A. Gude, N. Anderson, J. Ramsey, M. Thompson, M. Sullivan, V. Edwards, C. Gower, J. F. Cochrane, E. Irwin, and T. Walshe. 2013. Using structured decision making to manage disease risk for Montana wildlife. Wildlife Society Bulletin 37:107-114.
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April 2013
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Mitchell, M. S., J. A. Gude, D. E. Ausband, C. A. Sime, E. E. Bangs, M. D. Jimenez, C. M. Mack, T. J. Meier, and M. S. Nadeau. 2010. Temporal validation of an estimator for successful breeding pairs of wolves Canis lupus in the U.S. northern Rocky Mountains. Wildlife Biology. Wildlife Biology 16:101-106.
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April 2010
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Mitchell, M. S., H. Cooley, J. A. Gude, J. Kolbe, J. J. Nowak, K. M. Proffitt, S. N. Sells, and M. Thompson. 2018. Distinguishing values from science in decision making: setting harvest quotas for mountain lions in western Montana . Wildlife Society Bulletin DOI:10.1002/wsb.861.
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April 2018
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Mitchell, M. S., D. E. Ausband, C. A. Sime, E. E. Bangs, M. Jimenez, C. M. Mack, T. J. Meier, M. S. Nadeau, and D. W. Smith. 2008. Estimation of successful breeding pairs for wolves in the U. S. northern Rocky Mountains. Journal of Wildlife Management 72:881-891.
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May 2008
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Mitchell, A. E., F. Tuh, and T. E. Martin. 2016. Breeding biology of an endemic Bornean turdid: Fruithunter (Chlamydochaera jefferyi). Wilson Journal of Ornithology 129(1), 36-45.
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March 2017
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Miller, D. A. W, J. D. Nichols1, J. A. Gude3, L. N. Rich, K. M. Podruzny, J. E. Hines, and M. S. Mitchell. 2013. Determining Occurrence Dynamics when False Positives Occur: Estimating the Range Dynamics of Wolves from Public Survey Data. PLoS ONE 8(6): e65808. doi:10.1371/journal.pone.0065808.
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June 2013
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Merkle, J. A., N. J. Anderson, D. L. Baxley, M. Chopp, L. C. Gigliotti, J. A. Gude, T. M. Harms, H. E. Johnson, E. H. Merrill, M. S. Mitchell, T. W. Wong, G. P. Nelson, A. S. Norton, M. J. Sheriff, E. Tomasik, and K. R. VanBeek. 2019. A collaborative approach to bridging the gap between wildlife managers and researchers. Journal of Wildlife Management 83:1644–1651; DOI: 10.1002/jwmg.21759
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August 2019
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McCall, B.S., M.S. Mitchell, M.K. Schwartz, J. Hayden, S. Cushman, and W. Kasworm. 2013. Combined use of mark-recapture and genetic analyses reveals response of a black bear population to changes in food productivity. Journal of Wildlife Management 77:1572-1582.
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October 2013
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Massaro, M., A. Starling-Windhof, J. V. Briskie, and T. E. Martin. 2008. Introduced mammalian predators induce adaptive shifts in parental behaviour in an endemic New Zealand bird. PLoS One 3(6): e2331. doi:10. 1371/journal. pone. 0002331
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May 2008
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Martin, T.E., R.D. Bassar, S.K. Bassar, J.J. Fontaine, P. Lloyd, H. Mathewson, A. Niklison, and A. Chalfoun. 2006. Life history and ecological correlates of geographic variation in egg and clutch mass among passerine species. Evolution 60:390-398
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Abstract
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Download
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April 2006
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Broad geographic patterns in egg and clutch mass are poorly described, and potential causes of variation remain largely unexamined. We describe interspecific variation in avian egg and clutch mass within and among diverse geographic regions and explore hypotheses related to allometry, clutch size, nest predation, adult mortality, and parental care as correlates and possible explanations of variation. We studied 74 species of Passeriformes at four latitudes on three continents: the north temperate United States, tropical Venezuela, subtropical Argentina, and south temperate South Africa. Egg and clutch mass increased with adult body mass in all locations, but differed among locations for the same body mass, demonstrating that egg and clutch mass have evolved to some extent independent of body mass among regions. A major portion of egg mass variation was explained by an inverse relationship with clutch size within and among regions, as predicted by life-history theory. However, clutch size did not explain all geographic differences in egg mass; eggs were smallest in South Africa despite small clutch sizes. These small eggs might be explained by high nest predation rates in South Africa; life-history theory predicts reduced reproductive effort under high risk of offspring mortality. This prediction was supported for clutch mass, which was inversely related to nest predation but not for egg mass. Nevertheless, clutch mass variation was not fully explained by nest predation, possibly reflecting interacting effects of adult mortality. Tests of the possible effects of nest predation on egg mass were compromised by limited power and by counterposing direct and indirect effects. Finally, components of parental investment, defined as effort per offspring, might be expected to positively coevolve. Indeed, egg mass, but not clutch mass, was greater in species that shared incubation by males and females compared with species in which only females incubate eggs. However, egg and clutch mass were not related to effort of parental care as measured by incubation attentiveness. Ecological and life-history correlates of egg and clutch mass variation found here follow from theory, but possible evolutionary causes deserve further study.
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Martin, T.E., P.R. Martin, C.R. Olson, B.J. Heidinger, and J.J. Fontaine. 2000. Parental care and clutch sizes in North and South American birds. Science 287:1482-1485.
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Abstract
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Download
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December 2000
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The evolutionary causes of small clutch sizes in tropical and Southern Hemisphere regions are poorly understood. Alexander Skutch proposed 50 years ago that higher nest predation in the south constrains the rate at which parent birds can deliver food to young and thereby constrains clutch size by limiting the number of young that parents can feed. This hypothesis for explaining differences in clutch size and parental behaviors between latitudes has remained untested. Here, a detailed study of bird species in Arizona and Argentina shows that Skutch’s hypothesis explains clutch size variation within North and South America. However, neither Skutch’s hypothesis nor two major alternatives explain differences between latitudes.
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Martin, T.E., P. Lloyd, C. Bosque, D.C. Barton, A.L. Biancucci, Y.R. Cheng, and R. Ton. 2011. Growth rate variation among passerine species in tropical and temperate sites: An antagonistic interaction between parental food provisioning and nest predation risk. Evolution 65(6):1607-1622.
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June 2011
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Martin, T.E., E. Arriero, and A. Majewska. 2011. A trade-off between embroyonic development rate and immune function of avian offspring is revealed by considering embroyic temperature. Biol. Lett. 7:425-428.
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June 2011
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Martin, T. E., and J. L. Maron. 2012. Climate impacts on bird and plant communities from altered animal-plant interactions. Nature Climate Change 2: 195-200.
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Abstract
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February 2012
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The contribution of climate change to declining populations of organisms remains a question of outstanding concern1-3. Much attention to declining populations has focused on how changing climate drives phenological mismatches between animals and their food4-6. Effects of climate on plant communities may provide an alternative, but particularly powerful, influence on animal populations because plants provide their habitats. Here, we show that abundances of deciduous trees and associated songbirds have declined with decreasing snowfall over 22 years of study in montane Arizona, USA. We experimentally tested the hypothesis that declining snowfall indirectly influences plants and associated birds by allowing greater over-winter herbivory by elk (Cervus canadensis). We excluded elk from one of two paired snow-melt drainages (10 ha/drainage), and replicated this paired experiment across three distant canyons. Over six years, we reversed multi-decade declines in plant and bird populations by experimentally inhibiting heavy winter herbivory associated with declining snowfall. Moreover, predation rates on songbird nests decreased in exclosures, despite higher abundances of nest predators, demonstrating the over-riding importance of habitat quality to avian recruitment. Thus, our results suggest that climate impacts on a plant-animal interaction can have forceful ramifying effects on plants, birds, and ecological interactions.
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Martin, T. E., and H. Schwabl. 2008 Variation in maternal effects and embryonic development rates among passerine species. Philosophical Transactions of the Royal Society B 363: 1663-1674.
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March 2008
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Martin, T. E., S. K. Auer, R. D. Bassar, A. M. Niklison, P. Lloyd. 2007. Geographic variation in avian incubation periods and parental influences on embryonic temperature. Evolution, 61-11:2558-2569.
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November 2007
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Martin, T. E., R. Ton, and J. C. Oteyza. 2018. Adaptive influence of extrinsic and intrinsic factors on variation of incubation periods among tropical and temperate passerines. Auk 135: 101-113.
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January 2018
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Martin, T. E., R. Ton, and A. Niklison. 2013. Intrinsic vs. extrinsic influences on life history expression: metabolism and parentally-induced temperature influences on embryo development rate. Ecology Letters 16: 738-745.
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Abstract
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April 2013
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Intrinsic processes are assumed to underlie life history expression and trade-offs, but extrinsic inputs are theorized to shift trait expression and mask trade-offs within species. Here, we explore application of this theory across species. We do this based on parentally-induced embryo temperature as an extrinsic input, and mass-specific embryo metabolism as an intrinsic process, underlying embryonic development rate. We found that embryonic metabolism followed intrinsic allometry rules among 49 songbird species from temperate and tropical sites. Extrinsic inputs via parentally-induced temperatures explained the majority of variation in development rates and masked a relationship with metabolism; metabolism explained a minor proportion of the variation in development rates among species, and only after accounting for temperature effects. We discuss evidence that temperature further obscures the expected inter-specific trade-off between development rate and offspring quality. These results demonstrate the importance of considering extrinsic inputs to trait expression and trade-offs across species.
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Martin, T. E., R. D. Bassar, S. K. Bassar, J. J. Fontaine, P. Lloyd, H. Mathewson, A. Niklison, and A. Chalfoun. 2006. Life history and ecological correlates of geographic variation in egg and clutch mass among passerine species. Evolution 60:390-398.
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March 2006
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Martin, T. E., P. R. Martin, C. R. Olson, B. J. Heidinger, and J. J. Fontaine. 2000. Parental care and clutch sizes in North and South American birds. Science 287: 1482 1485.
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October 2000
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Martin, T. E., M. M. Riordan, R. Repin, J. C. Mouton, and W. M. Blake. 2017. Apparent annual survival estimates of tropical songbirds better reflect life history variation when based on intensive field methods. Global Ecology and Biogeography 26:1386–1397.
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December 2017
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Martin, T. E., J. Scott, and C. Menge. 2000. Nest predation increases with parental activity: separating nest site and parental activity effects. Proceedings of the Royal Society of London, Series B. 267:2287-2293.
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November 2000
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Martin, T. E., J. C. Oteyza, A. J. Boyce, P. Lloyd, and R. Ton. 2015. Adult mortality probability and nest predation rates explain parental effort in warming eggs with consequences for embryonic development time. American Naturalist 186: 223-236.
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Abstract
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August 2015
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The time that embryos take to develop is thought to affect mortality in later life because of physiological trade-offs associated with development time. Yet, an unexplored alternative hypothesis suggests that mortality may be the cause rather than consequence of embryo development time in birds; adult and offspring mortality may exert selection on parental effort in warming eggs to thereby determine embryo development times. We examined these possibilities based on field studies of 64 songbird species on four continents. Structural equation modeling showed that an association of age-specific mortality and embryonic development time was best explained by mortality as a cause of average embryonic temperature. Influence of age-specific mortality on parental effort in warming eggs is a unique result that follows from life history theory and provides a causal mechanism for explaining variation in embryonic development time across diverse species.
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Martin, T. E., J. C. Oteyza, A. E. Mitchell, A. L. Potticary, and P. Lloyd. 2015. Post-natal growth rates of diverse songbird species covary weakly with embryonic development rates and do not explain adult mortality probability. American Naturalist 185: 380-389.
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March 2015
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Martin, T. E., B. Tobalske, M. M. Riordan, S. Case, and K. P. Dial. 2018. Age and performance at fledging is a cause and consequence of juvenile mortality between life stages. Science Advances 4: eaar1988.
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Abstract
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June 2018
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Should they stay or should they leave? That is a critical question facing young birds in a nest as they mature. The answer has ramifications for juvenile mortality, an important influence on demography and fitness, but differs among species and the reasons why are unclear. The probability of young being eaten increases with each day they remain in the nest. We show that species at greater risk leave the nest at a younger age with less developed wings that cause poorer flight performance and greater subsequent mortality. Experimentally delayed fledging verifies that older age and better developed wings reduce juvenile mortality. Fitness benefits of staying in the nest to reduce fledgling mortality are opposed by nest predation costs, and parents and offspring conflict on the optimal resolution. Ultimately, fledging age and associated offspring development balance mortality in and out of the nest in a compromise between parents and offspring.
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Martin, T. E., A. P. Moller, S. Merino, and J. Clobert. 2001. Does clutch size evolve in response to parasites and immunocompetence? Proceedings of the National Academy of Sciences, USA 98: 2071-2076.
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February 2001
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Martin, T. E., A. J. Boyce, K. Fierro-Calderón, A. E. Mitchell, C. E. Armstad, J. Mouton, and E. E. Bin Soudi. 2017. Do enclosed nests provide greater thermal than nest predation benefits compared with open nests across latitudes? Functional Ecology 31: 1231-1240.
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August 2017
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Martin, T. E. and J. V. Briskie. 2009. Predation on dependent offspring: a review of the consequences for mean expression and phenotypic plasticity in avian life history traits. The Year in Evolutionary Biology 2009: Annals of the New York Academy of Sciences 1168: 201-217.
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June 2009
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Martin, T. E. and J. C. Mouton. 2020. Longer-lived tropical songbirds reduce breeding activity as they buffer impacts of drought. Nature Climate Change 10: https://doi.org/10.1038/s41558-020-0864-3.
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September 2020
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Martin, T. E. 2015. Consequences of habitat change and resource selection specialization for population limitation in cavity-nesting birds. Journal of Applied Ecology 52: 475–485.
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Abstract
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April 2015
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Summary.
1. Resource selection specialization may increase vulnerability of populations to environmental change. One environmental change that may negatively impact some populations is the broad decline of quaking aspen (Populus tremuloides), a preferred nest tree of cavity-nesting organisms who are commonly limited by nest-site availability. However, the long-term consequences of this habitat change for cavity-nesting bird populations are poorly studied.
2. I counted densities of woody plants and eight cavity-nesting bird species (six woodpeckers, Mountain Chickadee Poecile gambeli, House Wren Troglodytes aedon) over 29 years in 15 high elevation riparian drainages in Arizona, USA. I also studied nest tree use and specialization over time based on 4946 nests across species.
3. Aspen suffered a severe decline in availability over time, while understory woody plants and canopy canyon maple (Acer grandidentatum) also declined. The decline of understory plants resulted from increased elk (Cervus canadensis) browsing linked to declining snowfall, and the lack of tree recruitment caused the decline in canopy aspen and maple.
4. All six woodpecker species exhibited very high specialization (>95% of nests) on aspen for nesting, and densities of all species declined with aspen over time. Mountain Chickadees and House Wrens exhibited increasingly less specialization on aspen. Chickadees strongly increased in density over time, despite a relatively high specialization on aspen. Nest sites clearly were not limiting their population. House Wren densities declined modestly over time, but nest box addition experiments demonstrated that nest-site availability was not limiting their population. House Wren densities increased with understory vegetation recovery in elk exclosures compared with controls, demonstrating that the decline in understory vegetation on the broader landscape was the cause of their population decline. The increased densities in exclosures were facilitated by increased generalization in nest site use.
5. Synthesis and applications: Management should target species that specialize in resource selection on a declining resource, because these species are vulnerable to population problems. Species with greater resource selection generalization can reduce population impacts of environmental change. Resource generalization can allow a species, like the wren, to take advantage of a habitat refuge, such as provided by the elk exclosures. Yet, when habitat on the broader landscape is declining in quality, or higher quality refuges are lacking, then resource generalization cannot offset the broader negative changes, as demonstrated by the decline in wrens on the broader landscape. Ultimately, aspen is an important habitat for biodiversity, and land management programs need to protect and aid recovery of aspen habitats.
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Martin, T. E. 2008. Egg size variation among tropical and temperate songbirds: An embryonic temperature hypothesis. Proceedings of the National Academy of Sciences USA 105:9268-9271
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July 2008
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Martin, T. E. 2007. Climate correlates of 20 years of trophic changes in a high elevation riparian system. Ecology 88: 367-380.
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February 2007
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Martin, T. E. 2004. Avian life-history evolution has an eminent past: does it have a bright future? The Auk 121:289-301
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April 2004
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Martin, T. E. 2002. A new view for avian life history evolution tested on an incubation paradox. Proceedings of the Royal Society of London 269: 309-316.
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January 2002
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Martin, T. E. 2001. Abiotic vs. biotic influences on habitat selection of coexisting species, with implications for climate change. Ecology 82: 175-188.
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January 2001
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Martin, T. E. Age-related mortality explains life history strategies of tropical and temperate songbirds. Science 349: 966-970.
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August 2015
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Martin, T. E. 2014. A conceptual framework for clutch size evolution in songbirds. American Naturalist 183: 313-324.
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Abstract
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March 2014
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Mechanistic causes of evolved differences in clutch size among species remain debated. I propose a new theory (collection of hypotheses) that integrates aspects of prior hypotheses, while also including novel elements, to explain evolution of clutch size differences among species. I postulate that selection by nest predation on length of time that offspring remain in the nest and locomotor development at fledging determines mobility and extent of self-feeding of fledglings. Species with high nest predation risk produce fledglings with low mobility and slower development of self-feeding that require greater parental energy expenditure per offspring. The greater energy demands of less mobile fledglings constrain the number of offspring that parents can raise compared with species that have low nest predation risk. Differences in mobility also can potentially yield differences in fledgling survival among species and, thereby, influence the adaptive age of fledging. Finally, differences in adult mortality are proposed to favor evolution of differences in total parental energy expenditure among species to further influence clutch sizes. Data from the literature and from my Arizona site are used to provide initial, although indirect, support for several elements of this proposed theory, but more detailed tests are needed.
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Martin, T. E. 2011. The cost of fear. Science 334: 1353-1354.
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Abstract
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Publisher Website
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December 2011
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no abstract
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Martin, P. R., and T. E. Martin. 2001. Ecological and fitness consequences of coexistence in two congeneric wood warblers (Parulidae: Vermivora): a removal experiment. Ecology 82: 189-206.
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January 2001
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Martin, P. R., and T. E. Martin. 2001. Behavioral interactions between two coexisting wood warblers (Parulidae: Vermivora): experimental and empirical tests. Ecology 82: 207-218.
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January 2001
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M. S. Mitchell, J. A. Gude, K. Podruzny, E. E. Bangs, J. Hayden, R. M. Inman, M. Jimenez, Q. Kujala, D. H. Pletscher, J. Rachael, R. Ream, and J. Vore. Submitted. Management of wolves in the US Northern Rocky Mountains is Based on Sound Policy and Science. Science.
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June 2016
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Lukacs, P. M., M. S. Mitchell, M. Hebblewhite, B. K. Johnson, H. Johnson, M. Kauffman, K. Proffitt, P. Zager, J. Brodie, K. Hersey, A. A. Holland, M. Hurley, S. McCorquodale, A. Middleton, M. Nordhagen, J. J. Nowak, D. P. Walsh, and P. J. White. 2018. Factors influencing elk recruitment across ecotypes in the western United States. Journal of Wildlife Management DOI: 10.1002/jwmg.21438
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May 2018
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Lowe, W. H., T. E. Martin, D. K. Skelly, and H. A. Woods. 2020. Metamorphosis in an era of increasing climate variability. Trends in Ecology and Evolution 36: 360-375.
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Abstract
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January 2021
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Most animals have complex life cycles including some form of metamorphosis, a life stage transition in which individuals may be particularly vulnerable to environmental stressors.<b><i> </i></b>With climate change, individuals will be exposed to increasing thermal and hydrologic variability during metamorphosis, which may affect survival and performance through physiological, behavioral, and ecological mechanisms.<b> </b>Furthermore, because metamorphosis entails changes in traits and vital rates during a period of particular sensitivity, it is likely to play an important role in how populations respond to increasing climate variability. To identify mechanisms underlying population responses and associated trait and life history evolution, we need new approaches to estimate changes in individual traits and performance throughout metamorphosis, as well as new analytical models integrating metamorphosis as an explicit life stage.
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Loonam, K. L., P. M. Lukacs, D. E. Ausband, M. S. Mitchell, and H. R. Robinson. 2021. Assessing the robustness of a new method for estimating wildlife abundance using remote cameras. Ecological Applications. e02388. 10.1002/eap.2388
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August 2021
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Loonam, K. E., D. E. Ausband, P. M. Lukacs, M. S. Mitchell, and H. R. Robinson. 2021. Estimating abundance of an unmarked, low-density species using camera traps. Journal of Wildlife Management. 85: 87-96. https://doi.org/10.1002/jwmg.21950
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March 2021
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Lomáscolo, S., A. C. Monmany, A. Malizia, and T. E. Martin. 2010. Flexibility in nest site choice and nest success of Turdus rufiventris (Turdidae) in a montane forest in northwestern Argentina. Wilson Journal of Ornithology, 122:674-680.
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October 2010
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Loehle, C., P. Van Deusen, T. B. Wigley, M. S. Mitchell, S. H. Rutzmoser, J. Aggett, J. A. Beebe, and M. L. Smith. 2006. A Method for Landscape Analysis of Forestry Guidelines Using Bird Habitat Models and the Habplan Harvest Scheduler. Forest Ecology and Management 232:56-67.
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May 2006
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Lloyd, P., and T. E. Martin. 2016. Fledgling survival increases with development time and adult survival across north and south temperate zones. Ibis 158: 135–143.
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Abstract
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January 2016
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Avian life history theory predicts that high adult survival and populations near carrying capacity favour reduced clutch size and increased investment per offspring to increase juvenile survival. Consistent with this hypothesis, south temperate and tropical birds are commonly longer-lived and have smaller clutch sizes. Yet, comparative analyses of juvenile survival are largely lacking. We measured post-fledging survival for eight south-temperate passerines in South Africa, and combined our measurements with estimates from a review of published studies from around the world to test two predictions: 1) survival through the first few weeks post-fledging increases with adult survival and reduced brood size, and 2) south temperate and tropical species exhibit higher post-fledging survival than north temperate species associated with higher adult survival and smaller brood sizes. Using post-fledging survival estimates for 73 passerine species, we found that variation in post-fledging survival across species was explained by region and not by adult survival or brood size. South temperate species had higher post-fledging survival than both north temperate and tropical species. Post-fledging survival did not differ between north temperate and tropical species, but tropical species were under-represented. Our results highlight that adult and juvenile mortality do not simply covary, but they both differ between the northern and southern temperate regions. Given the importance of age-specific mortality to life history evolution, understanding these geographic patterns of mortality is important.
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Lloyd, P., W. A. Taylor, M. A. duPlessis, and T. E. Martin. 2009. Females increase reproductive investment in response to multiple helper benefits in the cooperatively breeding Karoo scrub-robin Cercotrichas coryphaeus. Journal of Avian Biology 40: 400-411.
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July 2009
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Lloyd, P., T. E. Martin, R. L. Redmond, U. Langner, and M. M. Hart. 2005. Linking demographic effects of habitat fragmentation across landscapes to continental source-sink dynamics. Ecological Applications 15: 1504-1514.
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September 2005
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Lloyd, P., T. E. Martin, R. L. Redmond, U. Langner, and M. M. Hart. 2005. Linking demographic effects of habitat fragmentation across landscapes to continental source-sink dynamics. Ecological Applications 15: 1504-1514.
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December 2005
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Lloyd, P., T. E. Martin, R. L. Redmond, M. M. Hart, U. Langner, and R. D. Bassar. 2006. Assessing the influence of spatial scale on the relationship between avian nesting success and forest fragmentation: a case study. Pp: 255-269 in J. Wu, K. B. Jones, H. Li, and O. Loucks (Editors) Scaling and Uncertainty Analysis In Ecology: Methods and Applications. Columbia University Press, New York, NY.
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March 2006
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Lloyd, P., T. E. Martin, A. Taylor, A. Braae and R. Altwegg. 2016. Age, sex, and social influences on adult survival in the co-operatively breeding Karoo scrub-robin. Emu 114: 394-401.
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Abstract
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December 2016
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Among cooperatively breeding species, helpers are hypothesised to increase the survival of breeders by reducing breeder workload in offspring care and increased group vigilance against predators. Furthermore, parental nepotism or other benefits of group living may provide a survival benefit to young that delay dispersal to help on the natal territory. We tested these hypotheses in the Karoo scrub-robin (Cercotrichas coryphaeus), a long-lived, facultative cooperatively breeding species of southern Africa in which male offspring delay dispersal until they obtain a breeding vacancy in a nearby territory, and helpers make substantial contributions to parental care. The hypothesis that helpers improve breeder survival was not clearly supported; annual apparent breeder survival in the presence of helpers (0.82) did not differ detectably from breeders without helpers (0.77). Survival of breeders that lost helpers (0.71) was lower, which may reflect a benefit of helpers or a poor territory. The hypothesis that helpers may gain a survival benefit from deferred breeding was not supported; male helpers had similar apparent survival as male breeders in the first year, and lower survival thereafter. Nonetheless, the relatively high survival of males through the first year following fledging (0.50) or independence (0.65) is consistent with high juvenile survival among species with delayed dispersal.
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Lloyd, P., F. Abadi, R. Altwegg, and T. E. Martin. 2014. South-temperate birds have equivalent annual adult survival to tropical birds in Africa. Journal of Avian Biology 45: 493-500.
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Abstract
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September 2014
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Life history theory predicts a trade-off between annual adult survival and fecundity. Globally, clutch size shows a latitudinal gradient among birds, with south-temperate species laying smaller clutches than north-temperate species, but larger clutches than tropical species. Tropical birds often have higher adult survival than north-temperate birds associated with their smaller clutches. However, the prediction that tropical birds should also have higher adult survival than south-temperate birds because of smaller clutch sizes remains largely untested. We measured clutch size and annual adult survival for 17 south-temperate African species to test two main predictions. First, we found strong support for a predicted trade-off between adult survival and clutch size among the south temperate species, consistent with life-history theory. Second, we compared our clutch size and survival estimates with published estimates for congeneric tropical African species to test the prediction of larger clutch size and lower adult survival among south-temperate than related tropical species. We found that south-temperate species laid larger clutches, as predicted, but had higher, rather than lower, adult survival than related tropical species. The latter result may be an artefact of different approaches to measuring survival, but the results suggest that adult survival is generally high in the south temperate region.
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Lloyd, P., B. D. Frauenknecht, M. A. du Plessis, and T. E. Martin. 2016. Comparative life history of the south-temperate Cape Penduline Tit (Anthoscopus minutus) and north-temperate Remizidae species. Journal of Ornithology doi:10.1007/s10336-016-1417-4.
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Abstract
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December 2016
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We studied the breeding biology of the south-temperate Cape Penduline Tit (Anthoscopus minutus) to enable a comparison of its life history with related, north-temperate members of the family Remizidae, namely Eurasian Penduline Tit (Remiz pendulinus) and Verdin (Auriparus flaviceps). We used this comparison to test key predictions of three hypotheses thought to explain latitudinal variation in life histories among bird species, the seasonality and food limitation hypothesis, nest predation hypothesis and adult mortality hypothesis. Contrary to the general pattern of smaller clutch size and lower adult mortality among south-temperate birds living in less seasonal environments, Cape Penduline Tit has a larger clutch size than Verdin, a clutch size similar to Eurasian Penduline Tit and higher adult mortality than both species. Cape Penduline Tit differs most notably in parental behavioural strategy, exhibiting bi-parental care at all stages of nesting together with facultative cooperative breeding, whereas Eurasian Penduline Tit has uni-parental care and Verdin has a combination of female-only incubation but bi-parental nestling care. Consequently, Cape Penduline Tit exhibits greater nest attentiveness during incubation, a greater per-nestling feeding rate and greater post-fledging survival. The relatively large clutch size, high nestling feeding rates and associated high adult mortality in Cape Penduline Tit in a less seasonal environment support key predictions of the adult mortality hypothesis and run counter to key predictions of the seasonality and food limitation hypothesis in explaining life history variation among Remizidae species. These results add to a growing body of evidence of the importance of age-specific mortality in shaping life history evolution.
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Lloyd, J., and T. E. Martin. 2004. Nest-site preference and maternal effects on offspring growth. Behavioral Ecology 15: 816-823.
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September 2004
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Lloyd, J. D., and T. E. Martin. 2005. Reproductive success of chestnut-collared longspurs in native and exotic grassland. Condor 107: 363-374.
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June 2005
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Lloyd, J. D., and T. E. Martin. 2003. Sibling competition and the evolution of parental developmental rates. Proceedings of the Royal Society of London, Series B 270: 735-740.
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March 2003
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LaManna, J. A., and T. E. Martin. 2017. Seasonal fecundity and consequences for λ are more strongly affected by direct than indirect predation effects across species. Ecology 98: 1829–1838
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May 2017
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LaManna, J. A., and T. E. Martin. 2017. Logging impacts on avian species richness and composition differ across latitudes and foraging and breeding habitat preferences. Biological Reviews 92: 1657-1674.
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August 2017
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LaManna, J. A., and T. E. Martin. 2015. Costs of fear: Behavioural and life-history responses to risk and their demographic consequences vary across species. Ecology Letters 19: 403–413.
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Abstract
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January 2016
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Behavioral responses to reduce predation risk might cause demographic ‘costs of fear’. The rare tests in terrestrial systems have focused on single species, but differences in life histories and ecology among species could yield differing costs that need to be understood to develop a general framework. Thus, we used natural and experimental variation in predation risk to test phenotypic responses and associated demographic costs for 10 songbird species. Increases in risk generally yielded increased time spent incubating eggs, which caused shorter development periods that reduce nest mortality. Parents also fed offspring less often with increased risk, but offspring maintained growth of structures used to escape predators (wings, tarsi) while sacrificing mass growth. Reproductive output from non-depredated nests declined along risk gradients, but the severity of this cost varied across species. Ultimately, phenotypic responses to predation risk are common across co-occurring species, but responses and demographic costs vary substantially.
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LaManna, J. A., A. B. Hemenway, V. Boccadori, and T. E. Martin. 2015. Bird species turnover is related to changing predation risk along a vegetation gradient. Ecology 96: 1670-1680.
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Abstract
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June 2015
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Aspen (Populus tremuloides) forests hold a high diversity of organisms but are increasingly invaded and replaced by conifers. The consequences of this habitat change for diversity and demography of organisms, such as birds, remains poorly understood. Conifer encroachment of an aspen stand may increase bird diversity by increasing vegetation complexity. However, the presence of conifers may also impact the reproductive success of birds via addition of conifer-dependent nest predators or via changes in habitat structural complexity. We examined the effects of conifer encroachment on the diversity, reproductive success, and population growth rates of birds in fourteen aspen stands that differed in the extent of conifer encroachment in Montana, USA. Bird species diversity increased with aspen stand area but was not correlated with proportion of conifer trees in a stand. Nest predator density increased with proportion of conifer trees in a stand. Conifer encroachment directly increased nest predation rates for four of ten open-cup nesting species and indirectly increased nest predation rates for three additional open-cup nesting species. Furthermore, increased nest predation with greater conifer encroachment transformed source breeding habitat (λ > 1) into sink habitat (λ < 1) for these seven species. Based on these results, conifer encroachment into aspen stands has the potential to decrease diversity, reproductive success, and population growth rates of songbirds, which emphasizes the value of large, relatively pure aspen stands on the landscape.
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Kie, J. G., J. Matthiopoulis, J. Fieberg, R. A. Powell, F. Cagnacci, M. S. Mitchell, J. Gaillard, and P. R. Moorcroft. 2010. The home range concept: are traditional estimators still relevant with modern telemetry technology? Philosophical Transactions of the Royal Society B 365:2221-2231.
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April 2010
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Khwaja, N., M. Massaro, T. E. Martin, and J. V. Briskie. 2019. Do parents synchronise nest visits as an antipredator adaptation in birds of New Zealand and Tasmania? Frontiers in Ecology and Evolution 7:389. doi: 10.3389/fevo.2019.00389
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October 2019
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Ketz, A. C., D. J. Storm, R. E. Barker, A. D. Apa, C. Oliva-Aviles, and D. P. Walsh. 2023. Assimilating ecological theory with empiricism: Using constrained generalized additive models to enhance survival analyses. Methods in Ecology and Evolution, 14, 952– 967. https://doi.org/10.1111/2041-210X.14057.
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Abstract
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January 2023
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1. Integrating ecological theory with empirical methods is ubiquitous in ecology using hierarchical Bayesian models. However, there has been little development focused on integration of ecological theory into models for survival analysis. Survival is a fundamental process, linking individual fitness with population dynamics, but incorporating life history strategies to inform survival estimation can be challenging because mortality processes occur at multiple scales. 2. We develop an approach to survival analysis, incorporating model constraints based on a species' life history strategy using functional analytical tools. Specifically, we structurally separate intrinsic patterns of mortality that arise from age-specific processes (e.g. increasing survival during early life stages due to growth or maturation, versus senescence) from extrinsic mortality patterns that arise over different periods of time (e.g. seasonal temporal shifts). We use shape constrained generalized additive models (CGAMs) to obtain age-specific hazard functions that incorporate theoretical information based on classical survivorship curves into the age component of the model and capture extrinsic factors in the time component.3. We compare the performance of our modelling approach to standard survival modelling tools that do not explicitly incorporate species life history strategy in the model structure, using metrics of predictive power, accuracy, efficiency and computation time. We applied these models to two case studies that reflect different functional shapes for the underlying survivorship curves, examining age-period survival for white-tailed deer Odocoileus virginianus in Wisconsin, USA and Columbian sharp-tailed grouse Tympanuchus phasianellus columbianus in Colorado, USA. 4. We found that models that included shape constraints for the age effects in the hazard curves using CGAMs outperformed models that did not include explicit functional constraints. We demonstrate a data-driven and easily extendable approach to survival analysis by showing its utility to obtain hazard rates and survival probabilities, accounting for heterogeneity across ages and over time, for two very different species. We show how integration of ecological theory using constrained generalized additive models, with empirical statistical methods, enhances survival analyses.
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Kaiser, S. A., T. E. Martin, J. C. Oteyza, C. Armstad, and R. C. Fleischer. 2018. Direct fitness benefits and kinship of social foraging groups in an Old World tropical babbler. Behavioral Ecology 29: 468-478.
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March 2018
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Jolley, D. B., S. S. Ditchkoff, B. D. Sparklin, L. B. Hanson, M. S. Mitchell, and J. B. Grand. 2010. Estimate of herpetofauna depredation by a population of wild pigs. Journal of Mammalogy 91:519-524.
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April 2010
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Inzalaco, H.N., E.E. Brandell, S. Wilson, M. Hunsaker, D.R. Stahler, K. Woelfel, D.P. Walsh, T. Nordeen, D.J. Storm, S.S. Lichtenberg, W.C. Turner. 2024. Detection of prions from spiked and free-ranging carnivore feces, Scientific Reports, 14: 3804. https://doi.org/10.1038/s41598-023-44167-7
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Abstract
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Publisher Website
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February 2024
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We assessed recovery and detection of PrP<sup>CWD</sup> by experimental spiking of PrP<sup>CWD </sup>into carnivore feces from 9 species sourced from CWD-free populations or captive facilities. We then applied this technique to detect PrP<sup>CWD</sup> from feces of predators and scavengers in free-ranging populations. Our results demonstrate that spiked PrP<sup>CWD</sup> is detectable from feces of free-ranging mammalian and avian carnivores using RT-QuIC. Results show that PrP<sup>CWD </sup>acquired in natural settings is detectable in feces from free-ranging carnivores, and that PrP<sup>CWD </sup>rates of detection in carnivore feces reflect relative prevalence estimates observed in the corresponding cervid populations. This study adapts an important diagnostic tool for CWD, allowing investigation of the epidemiology of CWD at the community-level.
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Inzalaco, H., F. Bravo-Risi, R. Morales, R., D. P. Walsh, D. J. Storm, J. Pedersen, W. C. Turner, and S. Lichtenberg. 2023. Ticks harbor and excrete chronic wasting disease prions. Scientific Reports 13, 7838 https://doi.org/10.1038/s41598-023-34308-3.
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May 2023
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Ibanez-Alamo, J.D., R. D. Magrath, J. C. Oteyza, A. D. Chalfoun, T. M. Haff, K. A. Schmidt, R. L. Thomson, and T. E. Martin. Nest predation research: Recent findings and future perspectives. Journal of Ornithology DOI 10.1007/s10336-015-1207-4.
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April 2015
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Henderson, C. R., M. S. Mitchell, W. L. Myers, and G. P. Nelson. 2018. Attributes of seasonal home range influence choice of migratory strategy in white-tailed deer. Journal of Mammalogy 99:89-96. DOI:10.1093/jmammal/gyx148
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February 2018
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Hanson, L. B., M. S. Mitchell, J. B. Grand, D. B. Jolley, W. D. Sparklin, and S. S. Ditchkoff. 2009. Effect of experimental manipulation on survival and recruitment of feral pigs. Wildlife Research. 36(3):185-191.
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April 2009
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Hanson, L. B., J. B. Grand, M. S. Mitchell, D. B. Jolley, B. D. Sparklin and S. S. Ditchkoff. 2008. Change-in-ratio density estimator for feral pigs is less biased than closed mark-recapture estimates. Wildlife Research 35(7): 695-699.
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December 2008
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Hanley, B. J., Carstensen, M., Walsh, D. P., Christensen, S. A., Storm, D. J., Booth, J. G., ... & Schuler, K. L. (2022). Informing Surveillance through the Characterization of Outbreak Potential of Chronic Wasting Disease in White-Tailed Deer. Ecological Modelling, 471, 110054. https://doi.org/10.1016/j.ecolmodel.2022.110054
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Abstract
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September 2022
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Understanding the role that an environmental prion reservoir plays in the outbreak dynamics of chronic wasting disease (CWD) in free ranging white-tailed deer (Odocoileus virginianus) is critical for the allocation of disease surveillance resources by state and provincial wildlife agencies. We hypothesized that demographic, ecological, and epidemiological configurations naturally attenuate epidemic risk despite the introduction of infectious prions into a susceptible population of deer, but the magnitude of infectious prions in the environmental prion reservoir complicate outbreak expectations. We developed a Susceptible-Latent-Exposed-Infective (SLEI) compartment model to represent the dynamics of CWD epidemics in free-ranging white-tailed deer, then used the basic reproductive ratio (�0) to pinpoint counties under which pathogenic introduction (transport of infectious bodily fluids, tissues, and carcasses through natural or anthropogenic means) naturally produced (or failed to produce) an epidemic. We found that the outlook for an epidemic hinged on transmission rates, the magnitude of environmental contamination, and system type (density-, frequency-, or density/frequency-dependent). CWD can persistently infect individuals living in a contaminated environment even if direct transmission is insufficient to sustain circulation. Theoretical results show that transmission of CWD cannot be exclusively density dependent, and must behave as either a mix between frequency and density dependent, or strictly frequency dependent. While the compartment model is a simplistic representation of reality and did not contain many complicating biological considerations, it was immediately useful in hypothesis generation, motivating the collection of additional data for use in more biologically detailed models, and in the allocation of finite surveillance resources to place emphasis on data collection in areas where an introduction of infectious prions is comparatively more likely to result in an epidemic.
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Hammond, C. A. M., M. S. Mitchell, and G. N. Bissell. In press. Territory occupancy by common loons in response to disturbance, habitat, and intraspecific relationships. Journal of Wildlife Management.
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April 2012
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Gude, J. A., M. S. Mitchell, R. E. Russell, C. A. Sime, E. E. Bangs, L. D. Mech, and R. R. Ream. 2012. Wolf population dynamics in U.S. northern Rocky Mountains are affected by recruitment and human-caused mortality. Journal of Wildlife Management 76:108-118.
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January 2012
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Gude, J. A., M. S. Mitchell, D. E. Ausband, C. A. Sime, and E. E. Bands. 2009. Internal validation of predicitive logistic regression models for decision making in wildlife management. Wildlife Biology.
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October 2009
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Goulding, W., and T. E. Martin. 2010. Description of the breeding biology of the Golden-faced Tyrannulet (Zimmerius chrysops) in Venezuela. Wilson Journal of Ornithology, 122:689-698
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October 2010
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Gilbertson, M. L., Ketz, A. C., Hunsaker, M., Jarosinski, D., Ellarson, W., Walsh, D. P., ... & Turner, W. C. (2022). Agricultural land use shapes dispersal in white-tailed deer (Odocoileus virginianus). Movement Ecology, 10(1), 43. https://doi.org/10.1186/s40462-022-00342-5
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Abstract
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October 2022
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Dispersal is a fundamental process to animal population dynamics and gene flow. In white-tailed deer (WTD; Odocoileus virginianus), dispersal also presents an increasingly relevant risk for the spread of infectious diseases. Across their wide range, WTD dispersal is believed to be driven by a suite of landscape and host behavioral factors, but these can vary by region, season, and sex. Our objectives were to (1) identify dispersal events in Wisconsin WTD and determine drivers of dispersal rates and distances, and (2) determine how landscape features (e.g., rivers, roads) structure deer dispersal paths.
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Gilbertson, M. L., Brandell, E. E., Pinkerton, M. E., Meaux, N. M., Hunsaker, M., Jarosinski, D., ... & Turner, W. C. (2022). CAUSE OF DEATH, PATHOLOGY, AND CHRONIC WASTING DISEASE STATUS OF WHITE-TAILED DEER (ODOCOILEUS VIRGINIANUS) MORTALITIES IN WISCONSIN, USA. The Journal of Wildlife Diseases, 58(4), 803-815. https://doi.org/10.7589/JWD-D-21-00202
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Abstract
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October 2022
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White-tailed deer (WTD; Odocoileus virginianus) are a critical species for ecosystem function and wildlife management. As such, studies of cause-specific mortality among WTD have long been used to understand population dynamics. However, detailed pathological information is rarely documented for free-ranging WTD, especially in regions with a high prevalence of chronic wasting disease (CWD). This leaves a significant gap in understanding how CWD is associated with disease processes or comorbidities that may subsequently alter broader population dynamics. We investigated unknown mortalities among collared WTD in southwestern Wisconsin, USA, an area of high CWD prevalence. We tested for associations between CWD and other disease processes and used a network approach to test for co-occurring disease processes. Predation and infectious disease were leading suspected causes of death, with high prevalence of CWD (42.4%; of 245 evaluated) and pneumonia (51.2%; of 168 evaluated) in our sample. CWD prevalence increased with age, before decreasing among older individuals, with more older females than males in our sample. Females were more likely to be CWD positive, and although this was not statistically significant when accounting for age, females were significantly more likely to die with end-stage CWD than males and may consequently be an underrecognized source of CWD transmission. Presence of CWD was associated with emaciation, atrophy of marrow fat and hematopoietic cells, and ectoparasitism (lice and ticks). Occurrences of severe infectious disease processes clustered together (e.g., pneumonia, CWD), as compared to noninfectious or low-severity processes (e.g., sarcocystosis), although pneumonia cases were not fully explained by CWD status. With the prevalence of CWD increasing across North America, our results highlight the critical importance of understanding the potential role of CWD in favoring or maintaining disease processes of importance for deer population health and dynamics.
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Ghalambor, C. K., and T. E. Martin. 2002. Comparative manipulation of predation in incubating birds reveals variability in the plasticity of responses. Behavioral Ecology 13: 101-108.
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January 2002
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Ghalambor, C. K., and T. E. Martin. 2001. Fecundity-survival trade-offs and parental risk-taking in birds. Science 292: 494-497
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April 2001
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Ghalambor, C. K., and T. E. Martin. 2000. Parental investment in two species of nuthatch varies with stage-specific predation risk and reproductive effort. Animal Behaviour 60: 263-267
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September 2000
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Ghalambor, C. K., S. I. Peluc, and T. E. Martin. 2013. Plasticity of parental care under the risk of predation: how much should parents reduce care? Biology Letters 9: 20130154.
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Abstract
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August 2013
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Predation can be an important agent of natural selection resulting in divergent parental care behaviors, and can also favor behavioral plasticity. Parent birds often decrease the rate that they visit the nest to provision offspring when perceived risk is high. Yet, the plasticity of such responses may differ among species as a function of either their relative risk of predation, or the mean rate of provisioning. Here, we report parental provisioning responses to experimental increases in the perceived risk of predation. We tested responses of 10 species of birds in north temperate Arizona and subtropical Argentina that differed in their ambient risk of predation. All species decreased provisioning rates in response to the nest predator but not a control. However, provisioning rates decreased more in species that had greater ambient risk of predation on natural nests. Thus, extent of plasticity varied among species in accord with risk.
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Forsman, J. T., and T. E. Martin. 2009. Habitat selection for parasite-free space by hosts of parasitic cowbirds. Oikos 118: 464-470.
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April 2009
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Fontaine, J.J., and T.E. Martin. 2006. Parent birds assess nest predation risk and adjust their reproductive strategies. Ecology Letters 9:428-434.
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Abstract
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Download
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April 2006
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Avian life history theory has long assumed that nest predation plays a minor role in shaping reproductive strategies. Yet, this assumption remains conspicuously untested by broad experiments that alter environmental risk of nest predation, despite the fact that nest predation is a major source of reproductive failure. Here, we examined whether parents can assess experimentally reduced nest predation risk and alter their reproductive strategies. We experimentally reduced nest predation risk and show that in safer environments parents increased investment in young through increased egg size, clutch mass, and the rate they fed nestlings. Parents also increased investment in female condition by increasing the rates that males fed incubating females at the nest, and decreasing the time that females spent incubating. These results demonstrate that birds can assess nest predation risk at large and that nest predation plays a key role in the expression of avian reproductive strategies.
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Fontaine, J.J., and T.E. Martin. 2006. Habitat selection responses of parents to offspring predation risk: an experimental test. American Naturalist 168:811-818.
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Abstract
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Download
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October 2006
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The ability of nest predation to influence habitat settlement decisions in birds is widely debated, despite its importance in limiting fitness. Here, we experimentally manipulated nest predation risk across a landscape and asked the question, do migratory birds assess and respond to variation in nest predation risk when choosing breeding habitats? We examined habitat preference by quantifying the density and settlement date of eight species of migratory passerines breeding in areas with and without intact nest predator communities. We found consistently more individuals nesting in areas with reduced nest predation than in areas with intact predator assemblages, although predation risk had no influence on settlement or breeding phenology. Additionally, those individuals occupying safer nesting habitats exhibited increased singing activity. These findings support a causal relationship between habitat choice and nest predation risk and suggest the importance of nest predation risk in shaping avian community structure and breeding activity.
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Fontaine, J.J., M. Martel, H.M. Markland, A.M. Niklison, K.L. Decker and T.E. Martin. 2007. Testing ecological and behavioral correlates of nest predation. Oikos 116:1887-1894.
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Abstract
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Download
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October 2007
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Variation in nest predation rates among bird species are assumed to reflect differences in risk that are specific to particular nest sites. Theoretical and empirical studies suggest that parental care behaviors can evolve in response to nest predation risk and thereby differ among ecological conditions that vary in inherent risk. However, parental care also can influence predation risk. Separating the effects of nest predation risk inherent to a nest site from the risk imposed by parental strategies is needed to understand the evolution of parental care. Here we identify correlations between risks inherent to nest sites, and risk associated with parental care behaviors, and use an artificial nest experiment to assess site-specific differences in nest predation risk across nesting guilds and between habitats that differed in nest predator abundance. We found a strong correlation between parental care behaviors and inherent differences in nest predation risk, but despite the absence of parental care at artificial nests, patterns of nest predation risk were similar for real and artificial nests both across nesting guilds and between predator treatments. Thus, we show for the first time that inherent risk of nest predation varies with nesting guild and predator abundance independent of parental care.
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Fontaine, J.J., E. Arriero, H. Schwable, and T.E. Martin. 201). Nest predation and circulating corticosterone levels within and among species. Condor 113:(825-833)
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Download
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November 2011
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Fontaine, J. J., and T. E. Martin. 2006. Parent birds assess nest predation risk and adjust their reproductive strategies. Ecology Letters 9: 428-434.
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March 2006
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Fontaine, J. J., and T. E. Martin. 2006. Experimental test of nest predation influences on adult habitat selection in a breeding bird community. American Naturalist 168: 811-818.
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December 2006
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Fontaine, J. J., M. Martel, H. M. Markland, A. Niklison, K. L. Decker, and T. E. Martin. 2007. Testing ecological and behavioral correlates of nest predation. Oikos 116: 1887-1894.
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November 2007
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Fierro-Calderon, K., and T. E. Martin. 2007. Reproductive biology of the Violet-chested Hummingbird in Venezuela and comparisons with other tropical and temperate hummingbirds. Condor 109:680-685.
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April 2007
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Ferretti, V., P. E. Llambias, and T. E. Martin. 2005. Life history differences between poulations of a Neotropical thrush challenge food limitation theory. Proceedings of the Royal Society of London B 272:769-773.
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April 2005
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Fedy, B. C., and T. E. Martin. 2009. Male songbirds provide indirect parental care by guarding females during incubation. Behavioral Ecology 20: 1034-1038.
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August 2009
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Eacker, D. R., M. Hebblewhite, K. M. Proffitt, B. S. Jimenez, M. S. Mitchell, and H. S. Robinson. 2016. Landscape-level effects of risk factors on annual elk calf survival in a multiple carnivore system. Journal of Wildlife Management 80:1345-1359.
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August 2016
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Donovan, T. M., C. J. Beardmore, D. N. Bonter, J. K. Brawn, R. J. Cooper, J. A. Fitzgerald, R. Ford, S. A. Gauthreaux, T. L. George, W. C. Hunter, T. E. Martin, J. Price, K. V. Rosenberg, P. D. Vickery, and T. Bently Wigley. 2002. Priority research needs for the conservation of Neotropical migrant landbirds. Journal of Field Ornithology 73:329-339.
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December 2002
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Ditchkoff, S. S., D. B. Jolley, B. D. Sparklin, L. B. Hanson, M. S. Mitchell, and J. B. Grand. 2012. Reproduction in a Population of Wild Pigs (Sus scrofa) Subjected to Lethal Control. Journal of Wildlife Management 76:1235-1240.
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August 2012
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Delgado Rivas, M., N. Ferrari, A. Fanelli, S. Muset, C. L. Thompson, C. L. White, D. P. Walsh, C. Wannous, and P. Tizzani. 2023. Wildlife health surveillance: gaps, needs and opportunities. World Organisation for Animal Health The Scientific and Technical Review. 41 (2).
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Abstract
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March 2023
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Disease emergence represents a global threat for public health, economy, and biological conservation, most of the emerging zoonotic diseases have an animal origin of which the majority of these are from wildlife. To prevent their spread and to support the implementation of control measures, disease surveillance and reporting systems are needed, and due to globalisation, these activities should be carried out at the global level. To define the main gaps effecting the performances of wildlife health surveillance and reporting systems globally, we analysed data from a questionnaire sent to National Focal Points of the World Organisation for Animal Health that inquired on structure and limits of wildlife surveillance and reporting systems in their territories. The response from 103 Members, covering all world areas, showed that 54.4% of them have a wildlife disease surveillance programme and 66% implemented a strategy to manage disease spread. The lack of dedicated budget affected the possibility of outbreak investigations, sampling collection, and diagnostic testing. Although most Members maintain records relating to wildlife mortality or morbidity events in centralised databases, data analyses and disease risk assessment are reported as priority needs. Our evaluation of surveillance capacity showed an overall low level with marked variability between Members that was not restricted to specific geographical area. Increased wildlife disease surveillance globally would help in understanding and managing risks to animal and public health. Moreover, consideration of the influence of socio-economic, cultural, and biodiversity aspects could improve disease surveillance under a One Health approach.
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Decker, K., A. Niklison, and T. E. Martin. 2007. First description of the nest, eggs, and breeding behavior of the Merida Tapaculo (Scytalopus meridanus). Wilson Journal of Ornithology 119: 121-124.
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February 2007
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DeVoe, J., K. M. Proffitt, M. S. Mitchell, C. Jourdonnais, K. J. Barker. 2019. Elk Forage and Risk Tradeoffs during the Fall Archery Season. Journal of Wildlife Management.
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May 2019
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Cox, W. A., and T. E. Martin. 2009. Breeding biology of the Three-striped Warbler in Venezuela: A contrast between tropical and temperate parulids. Wilson Journal of Ornithology 121: 667-678.
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December 2009
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Conway, C. K., and T. E. Martin. 2000. Effects of ambient temperature on avian incubation strategies: a model and test. Behavioral Ecology 11: 178-188.
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November 2000
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Conway, C. J., and T. E. Martin. 2000. Evolution of avian incubation behavior: influence of food, temperature, and nest predation. Evolution 54:670-685.
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September 2000
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Clark, M., and T. E. Martin. 2007. Modeling trade-offs in avian life history traits and consequences for population growth. Ecological Modeling, 209:110-120.
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November 2007
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Cheng, Y., and T. E. Martin. 2012. Nest predation risk and growth strategies of Passerine species: Grow fast or develop traits to escape risk? American Naturalist 180: 285-295.
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Abstract
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September 2012
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Different body components are thought to trade-off in their growth and development rates, but the causes for relative prioritization of any trait remains a critical question. Offspring of species at higher risk of predation might prioritize development of locomotor traits that facilitate escaping risky environments over growth of mass. We tested this possibility in 12 altricial Passerine species that differed in their risk of nest predation. We found that rates of growth and development of mass, wings, and endothermy increased with nest predation risk across species. In particular, species with higher nest predation risk exhibited relatively faster growth of wings than mass, fledged with relatively larger wing sizes and smaller mass, and developed endothermy earlier at relatively smaller mass. This differential development can facilitate both escape from predators and survival outside of the nest environment. Tarsus growth was not differentially prioritized with respect to nest predation risk and, instead, all species achieved adult tarsus size by age of fledging. We also tested if different foraging modes (aerial, arboreal and ground foragers) might explain the variation of differential growth of locomotor modules, but found little residual variation was explained. Our results suggest that differences in nest predation risk among species are associated with relative prioritization of body components to facilitate escape from the risky nest environment.
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Chalfoun, A.D. and T.E. Martin. 2010. Facultative nest patch shifts in response to nest predation risk in the Brewer's sparrow: a "win-stay, lose-switch" strategy? Oecologia 163:885-892.
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October 2010
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Chalfoun, A., and T. E. Martin. 2010. Within-season facultative shifts in nest-site selection in response to offspring predation risk: A win-stay, lose-switch strategy. Oecologia 163:885-892.
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September 2010
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Chalfoun, A., and T. E. Martin. 2010. Parental investment decisions in response to ambient nest predation risk versus actual predation on the prior nest. The Condor 112:701-710.
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October 2010
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Chalfoun, A., and T. E. Martin. 2009. Habitat structure mediates predation risk for sedentary prey: experimental tests of alternative hypotheses. Journal of Animal Ecology 78: 497-503.
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April 2009
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Chalfoun, A. D., and T. E. Martin. 2007. Latitudinal variation in avian incubation attentiveness and a test of the food limitation hypothesis. Animal Behaviour 73:579-585.
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January 2007
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Chalfoun, A. D., and T. E. Martin. 2007. Assessments of habitat preferences and quality depend on spatial scale and metrics of fitness. Journal of Applied Ecology 44:983-992.
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August 2007
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Chalfoun, A. D., and T. E. Martin. 2007. Latitudinal variation in avian incubation attentiveness and an experimental test of the food limitation hypothesis. Animal Behaviour 73: 579-585.
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September 2007
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Chalfoun, A. D., and T. E. Martin. 2007. Assessments of habitat preferences and quality depend on spatial scale and metrics of fitness. J. of Applied Ecology 44: 983-992.
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September 2007
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Chalfoun, A. D., and T. E. Martin. 2009. Habitat structure mediates predation risk for sedentary prey: Experimental tests of alternative hypotheses. J. of Animal Ecology 78:497-503.
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September 2009
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Cavitt, J. F., and T. E. Martin. 2002. Effects of forest fragmentation on brood parasitism and nest predation in eastern and western landscapes. Studies in Avian Biology 25: 73-80.
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December 2002
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Canterbury, G. E., T. E. Martin, D. R. Petit, L. J. Petit, and D. F. Bradford. 2000. Bird communities and habitat as ecological indicators of forest condition in regional monitoring. Conservation Biology 14: 544-558.
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May 2000
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Callan, L. M., F. A. La Sorte, T. E. Martin, and V. G. Rohwer. 2019. Higher nest predation favors rapid fledging at the cost of plumage quality in nestling birds. American Naturalist 193: 717-724.
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Abstract
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May 2019
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Life-history theory predicts that rapid growth comes at a cost to trait quality or adult longevity. However, this predicted trade-off has been weak or absent in passerine birds that vary in their growth rates. Trade-offs associated with fast growth and short development time might be better expressed in ephemeral traits because costs associated with these traits can be recovered or eliminated when they are replaced. We examined whether shorter development time yielded lower quality nestling body feathers, an ephemeral trait. We found a strong trade-off whereby nestlings that spend more time in the nest growing slowly produced higher quality plumage across 123 temperate and tropical species. This trade-off appears largely driven by nest predation because high predation rates favor rapid nestling growth and short development times at the cost of plumage quality. Our results suggest that ephemeral traits, like nestling body feathers, which can be replaced later, have the potential to minimize other longer-term trade-offs that arise during the rapid development of multiple traits.
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Cain, J.W. III, and M.S. Mitchell. 2018. Evaluation of Key Scientific Issues in the Report, “State of the Mountain Lion: a Call to End Trophy Hunting of America’s Lion”. USGS Open File Report 2018-1128.
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Download
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August 2018
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Cadena, C. D., S. C�rdoba-C�rdoba, G. A. Londo�o, D. Calder�n-F., T. E. Martin, M. P. Baptiste. 2007. Nesting and singing behavior of Common Bush-Tanagers (Chlorospingus ophthalmicus) in South America. Ornitologia Colombiana 5: 54-63.
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August 2007
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Burgener, K. R., Lichtenberg, S. S., Lomax, A., Storm, D. J., Walsh, D. P., & Pedersen, J. A. (2022). Diagnostic testing of chronic wasting disease in white-tailed deer (Odocoileus virginianus) by RT-QuIC using multiple tissues. Plos one, 17(11), e0274531. https://doi.org/10.1371/journal.pone.0274531
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Abstract
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November 2022
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Chronic wasting disease (CWD) is a fatal prion disease affecting cervids (deer, elk, moose). Current methods to monitor individual disease state include highly invasive antemortem rectal biopsy or postmortem brain biopsy. Efficient, sensitive, and selective antemortem and postmortem testing of populations would increase knowledge of the dynamics of CWD epizootics as well as provide a means to track CWD progression into previously unaffected areas. Here, we analyzed the presence of CWD prions in skin samples from two easily accessed locations (ear and belly) from 30 deceased white-tailed deer (Odocoileus viginianus). The skin samples were enzymatically digested and analyzed by real-time quaking-induced conversion (RT-QuIC). The diagnostic sensitivity of the ear and belly skin samples were both 95%, and the diagnostic specificity of the ear and belly skin were both 100%. Additionally, the location of the skin biopsy on the ear does not affect specificity or sensitivity. These results demonstrate the efficacy of CWD diagnosis with skin biopsies using RT-QuIC. This method could be useful for large scale antemortem population testing.
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Brodie, J., H. Johnson, M. S. Mitchell, P. Zager, K. Proffitt, M. Hebblewhite, M. Kauffman, B. Johnson, J. Bissonette, C. Bishop, J. Gude, J. Herbert, K. Hersey, M. Hurley, P. M. Lukacs, S. McCorquodale, E. McIntire, J. Nowak, H. Sawyer, D. Smith, and P.J. White. Submitted. Relative influence of human harvest, carnivores, and weather on adult female elk survival across western North America. Journal of Applied Ecology 50:295–305.
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April 2013
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Brandell, E. E., Storm, D. J., Van Deelen, T. R., Walsh, D. P., & Turner, W. C. (2022). A call to action: Standardizing white-tailed deer harvest data in the Midwestern United States and implications for quantitative analysis and disease management. Frontiers in Ecology and Evolution, 10, 943411. https://doi.org/10.3389/fevo.2022.943411
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Abstract
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November 2022
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Recreational hunting has been the dominant game management and conservation mechanism in the United States for the past century. However, there are numerous modern-day issues that reduce the viability and efficacy of hunting-based management, such as fewer hunters, overabundant wildlife populations, limited access, and emerging infectious diseases in wildlife. Quantifying the drivers of recreational harvest by hunters could inform potential management actions to address these issues, but this is seldom comprehensively accomplished because data collection practices limit some analytical applications (e.g., differing spatial scales of harvest regulations and harvest data). Additionally, managing large-scale issues, such as infectious diseases, requires collaborations across management agencies, which is challenging or impossible if data are not standardized. Here we discuss modern issues with the prevailing wildlife management framework in the United States from an analytical point of view with a case study of white-tailed deer (Odocoileus virginianus) in the Midwest. We have four aims: (1) describe the interrelated processes that comprise hunting and suggest improvements to current data collections systems, (2) summarize data collection systems employed by state wildlife management agencies in the Midwestern United States and discuss potential for large-scale data standardization, (3) assess how aims 1 and 2 influence managing infectious diseases in hunted wildlife, and (4) suggest actionable steps to help guide data collection standards and management practices. To achieve these goals, Wisconsin Department of Natural Resources disseminated a questionnaire to state wildlife agencies (Illinois, Indiana, Iowa, Kentucky, Michigan, Minnesota, Missouri, Ohio, Wisconsin), and we report and compare their harvest management structures, data collection practices, and responses to chronic wasting disease. We hope our "call to action" encourages re-evaluation, coordination, and improvement of harvest and management data collection practices with the goal of improving the analytical potential of these data. A deeper understanding of the strengths and deficiencies of our current management systems in relation to harvest and management data collection methods could benefit the future development of comprehensive and collaborative management and research initiatives (e.g., adaptive management) for wildlife and their diseases.
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Boyce, A.J., B.G. Freeman, A.E. Mitchell and T.E. Martin. 2015. Clutch size declines with elevation in tropical birds. Auk 132: 424-432.
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April 2015
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Boyce, A. J. and T. E. Martin. 2018. Interspecific aggression among parapatric and sympatric songbirds on a tropical elevational gradient. Behavioral Ecology 30: 541-547.
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March 2019
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Boyce, A. J. and T. E. Martin. 2017. Contrasting latitudinal patterns of life-history divergence in two genera of new world thrushes (Turdinae). Journal of Avian Biology 48: 1-10.
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January 2017
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Borg., N. J., M. S. Mitchell, P. M. Lukacs, C. M. Mack, L. P. Waits, and P. R. Krausman. 2017. Behavioral connectivity among bighorn sheep suggests potential for disease spread. Journal of Wildlife Management 81:38-45 DOI: 10.1002/jwmg.21169
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January 2017
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Biancucci, L., and T. E. Martin. 2008. First description of the breeding biology and natural history of the Ochre-breasted Brush-finch (Atlapetes semirufus) in Venezuela. Wilson Journal of Ornithology 120: 856-862.
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November 2008
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Biancucci, L. and T.E. Martin. 2010. Can selection on nest size from nest predation explain the latitudinal gradient in clutch size? Journal of Animal Ecology 79:1086-1092.
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September 2010
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Biancucci, A. L., and T. E. Martin. 2010. Can selection on nest size from nest predation explain the latitudinal gradient in clutch size? Journal of Animal Ecology 79: 1086-1092.
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August 2010
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Beyer, H. L., D. T. Haydon, J. M. Morales, J. L. Frair, M. Hebblewhite, M. S. Mitchell, and J. Matthiopoulos. 2010. The interpretation of habitat preference metrics under use-availability designs. Philosphical Transactions of the Royal Society B 365:2245-2254.
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April 2010
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Bassing, S. B., D. E. Ausband, M. S. Mitchell, P. M. Lukacs, A. Keever, G. Hale, and L. Waits. 2019. Stable Pack Abundance and Distribution in a Harvested Wolf Population. Journal of Wildlife Management.
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March 2019
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Bassing, S. B., D. E. Ausband, M. S. Mitchell, M. Schwartz, Michael, J. J. Nowak, G. Hale, and L. Waits, 2020. Immigration Does Not Offset Harvest Mortality in a Cooperatively Breeding Carnivore. Animal Conservation.
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May 2020
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Barker, K. J., M. S. Mitchell, and K. M. Proffitt. 2019. Native Forage Mediates Influence of Irrigated Agriculture on Migratory Behavior of Elk. Journal of Animal Ecology.
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July 2019
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Barker, K. J., M. S. Mitchell, K. M. Proffitt, and J. D. DeVoe. 2018. Land management alters traditional nutritional benefits of migration for elk.
Journal of Wildlife Management. DOI: 10.1002:jwmg.21564.
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September 2018
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Barber, D. R., T. E. Martin, M. A. Melchiors, R. E. Thill, and T. B. Wigley. 2001. Nesting success of birds in different silvicultural treatments in Southeastern U. S. pine forests. Conservation Biology 15: 196-207.
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February 2001
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Banks, A. B., and T. E. Martin. 2000. Variation among host species in probability of parasitism by brown-headed cowbirds: the role of host activity. Behavioral Ecology 12: 31-40
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January 2001
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Banks, A. B., and T. E. Martin. 2000. Variation among host species in probability of parasitism by brown headed cowbirds: the role of host activity. Behavioral Ecology 12: 31-40.
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February 2000
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Badyaev, A. V., and T. E. Martin. 2000. Sexual dimorphism in relation to current selection in the House Finch. Evolution 54: 987-997.
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August 2000
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Badyaev, A. V., and T. E. Martin. 2000. Individual variation in growth trajectories: Phenotypic and genetic correlations in ontogeny of the house finch (Carpodacus mexicanus). Journal of Evolutionary Biology 13: 290-301.
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April 2000
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Ausband, D.E., S.B. Bassing, and M.S. Mitchell. 2020. Environmental and social influences on wolf howling behavior. Ethology. 126:890-899. https://doi.org/10.1111/eth.13041
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June 2020
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Ausband, D.E., J.Young, B. Fannin, M.S. Mitchell, J.L. Stenglein, L.P. Waits, and J.A. Shivik. 2011. Hair of the dog: obtaining samples from coyotes and wolves noninvasively. Wildlife Society Bulletin 35:105-111.
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Abstract
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Publisher Website
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May 2011
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Canids can be difficult to detect and their populations difficult to monitor. We tested whether hair samples could be collected from coyotes (Canis latrans) in Texas, USA and gray wolves (C. lupus) in Montana, USA using lure to elicit rubbing behavior at both man-made and natural collection devices. We used mitochondrial and nuclear DNA to determine whether collected hair samples were from coyote, wolf, or nontarget species. Both coyotes and wolves rubbed on man-made barbed surfaces but coyotes in Texas seldom rubbed on hanging barbed surfaces. Wolves in Montana showed a tendency to rub at stations where natural-material collection devices (sticks and debris) were present. Time to detection was relatively short (5 nights and 4 nights for coyotes and wolves, respectively) with nontarget and unknown species comprising approximately 26% of the detections in both locations. Eliciting rubbing behavior from coyotes and wolves using lures has advantages over opportunistic genetic sampling methods (e.g., scat transects) because it elicits a behavior that deposits a hair sample at a fixed sampling location, thereby increasing the efficiency of sampling for canids. Hair samples from rub stations could be used to provide estimates of abundance, measures of genetic diversity and health, and detection-nondetection data useful for cost-effective population monitoring.
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Ausband, D. E., M. S. Mitchell, and L. P. Waits. 2017. Effects of breeder turnover and harvest on group composition and recruitment in a social carnivore. Journal of Animal Ecology DOI: 10.1111/1365-2656.12707
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July 2017
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Ausband, D. E., M. S. Mitchell, S. Bassing, and C. White. 2013. No trespassing: using a biofence to manipulate carnivore movements. Wildlife Research 40:207-216.
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September 2013
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Ausband, D. E., M. S. Mitchell, S. B. Bassing, M. Nordhagen, D. W. Smith, and D. R. Stahler. 2016. Dog days of summer: influences on decision of wolves to move pups. Journal of Mammalogy 97:1282-1287.
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July 2016
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Ausband, D. E., M. S. Mitchell, S. B. Bassing, A. Morehouse, D. W. Smith, and D. Stahler. 2016. Individual, group, and environmental influences on helping behavior in a social carnivore. Ethology 122:1-10.
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October 2016
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Ausband, D. E., M. S. Mitchell, K. Doherty, P. Zager, C. M. Mack, and J. Holyan. 2010. Surveying predicted rendezvous sites to monitor gray wolf populations. Journal of Wildlife Management 74:1043-1049.
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April 2010
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Ausband, D. E., M. S. Mitchell, C. R. Stansbury, J. L. Stenglein, and L. P. Waits. 2017. Effects of harvest on recruitment and groups of cooperative breeders. Proceedings of the Royal Society B 284: 20170580
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July 2017
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Ausband, D. E., L. N. Rich, E. M. Glenn, M. S. Mitchell, P. Zager, C. M. Mack, D. A. W. Miller, and B. B. Ackerman. 2014. Monitoring Gray Wolf Populations Using Multiple Survey Methods. Journal of Wildlife Management 78:335-346.
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February 2014
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Ausband, D. E., J. Skrivseth, and M. S. Mitchell. 2011. An Automated Device for Provoking and Capturing Wildlife Calls. Wildlife Society Bulletin 35:498-503.
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December 2011
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Ausband, D. E. and M. S. Mitchell. Submitted. The effect of group size on recruitment depends on population density in a cooperatively breeding carnivore. Journal of Animal Ecology.
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April 2021
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Auer, S.K., R.D. Bassar, J.J. Fontaine, and T.E. Martin. 2007. Breeding biology of passerines in a subtropical montane forest in Northwestern Argentina. Condor 109:321-333.
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Abstract
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Download
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April 2007
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The breeding ecology of south temperate bird species is less widely known than that of north temperate species, yet because they comprise a large portion of the world’s avian diversity, knowledge of their breeding ecology can contribute to a more comprehensive understanding of the geographic diversity of avian reproductive traits and life history strategies. We provide the first detailed examination of the reproductive strategies of 18 forest passerines of subtropical, northwestern Argentina. Mean clutch sizes were smaller and egg mass was greater than for north temperate birds, but differed among species and nest types, with cavity-nesters having larger clutches than species with opencup and enclosed nests. Across all species, the average breeding season duration was 50 days; thus, the common perception that southern species have smaller clutch sizes because of longer breeding seasons is not supported in this community. Daily nest predation rates were influenced by nest type, cavity nests suffering the least from predation, as found in north temperate systems. Only females incubated eggs in all but one species, whereas both parents fed and cared for nestlings in all species. Mean nest attentiveness was low compared to north temperate passerines. Mean hourly nestling feeding rates differed among species and were negatively related to nest predation risk. In short, coexisting species in this subtropical forest varied in their life history strategies, in part correlated with variation in nest predation risk, but also differing from north temperate species.
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Auer, S. K., and T. E. Martin. 2013. Climate change has indirect effects on resource use and overlap among coexisting bird species with negative consequences for their reproductive success. Global Change Biology 19: 411-419.
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January 2013
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Auer, S. K., R. D. Bassar, J. J. Fontaine, and T. E. Martin. 2007. Breeding biology of passerines in a subtropical montane forest in northwestern Argentina. The Condor 109:321-333.
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January 2007
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Auer, S. K., R. D. Bassar and T. E. Martin. 2007. Biparental incubation in the chestnut-vented tit-babbler Parisoma subcaerulemum: mates devote equal time, but males keep eggs warmer. Journal Avian Biology. 38: 278-283.
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February 2007
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Arriero, E., A. Majewska, and T. E. Martin. 2013. Ontogeny of constitutive immunity: maternal vs endogenous influences. Functional Ecology 27: 472–478.
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Abstract
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February 2013
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Summary
1. Variation in ontogeny and strength of immune defense mechanisms can be integrally related to variation in life history strategies and determined by trade-offs during development. However, little is known about the ontogeny of immune function in wild birds, especially in altricial birds and in a comparative context across altricial species with diverse life history strategies.
2. In this study we examined the ontogeny of constitutive immunity in a group of 22 Passerine species sampled in tropical Venezuela and north temperate Arizona.
3. Our results show activity of constitutive components of the immune defense at 1-3 days post-hatching, and an increase in immune activity with age. Inter-specific variation in immune activity at hatching was mainly explained by extrinsic factors mediated by the mother (egg size and egg temperature), suggesting an important role of maternal effects on offspring immunity at hatching. In contrast, the increase in agglutination activity with age suggests that immune function in older nestlings reflects intrinsic development. The increase in immune activity was greater in species that hatched with lower initial levels, and was somewhat negatively related to growth rate across species.
4. Our results suggest slower intrinsic development of immune function may be compensated by larger maternal contributions. Slower intrinsic development of immune function, in turn, may reflect a trade-off with faster somatic growth. Our study highlights the importance of both maternal (extrinsic) and endogenous (intrinsic) contributions to variation in immune function across altricial species that may reflect an important axis of developmental strategies.
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