Massachusetts Project: Effects of habitat, density, and climate on moose and winter tick ecology in the northeast US

Massachusetts Project

Effects of habitat, density, and climate on moose and winter tick ecology in the northeast US

September 2021 - August 2024

Personnel

Participating Agencies

I dont know what goes here

Moose (Alces alces) populations in the northeastern US have declined by over 50% in the past 15 years. Winter tick (Dermacentor albipictus) infestations are a major driver of moose population trends, negatively affecting both survival and reproduction. We will partner with cooperators in Maine, Massachusetts, New Hampshire, New York, and Vermont to measure winter tick and moose distribution and abundance on a large camera trapping array. We will use our data to evaluate moose-tick dynamics across the full distribution of moose in New England. In doing so we can examine the relative importance of climate, habitat, and moose density in driving damaging epizootic conditions.

Research Publications

Research Publications	Publication Date
Sirén, A.P.K., J. Berube, L.A. Clarfeld, C.F.Sullivan, B. Simpson, T.L. Wilson. 2024. Accounting for missing ticks: Use (or lack thereof) of hierarchical models in tick ecology studies. Ticks and Tickborne Diseases 15:102342. DOI: 10.1016/j.ttbdis.2024.102342. \| Abstract \| Publisher Website	April 2024	Ixodid (hard) ticks play important ecosystem roles and have significant impacts on animal and human health via tick-borne diseases and physiological stress from parasitism. Tick occurrence, abundance, activity, and key life-history traits are highly influenced by host availability, weather, microclimate, and landscape features. As such, changes in the environment can have profound impacts on ticks, their hosts, and the spread of diseases. Researchers recognize that spatial and temporal factors influence activity and abundance and attempt to account for both by conducting replicate sampling bouts spread over the tick questing period. However, common field methods notoriously underestimate abundance, and it is unclear how (or if) tick studies model the confounding effects of factors influencing activity and abundance. This step is critical as unaccounted variance in detection can lead to biased estimates of occurrence and abundance. We performed a descriptive review to evaluate the extent to which studies account for the detection process while modeling tick data. We also categorized the types of analyses that are commonly used to model tick data. We used hierarchical models (HMs) that account for imperfect detection to analyze simulated and empirical tick data, demonstrating that inference is muddled when detection probability is not accounted for in the modeling process. Our review indicates that only 5 of 412 (1 %) papers explicitly accounted for imperfect detection while modeling ticks. By comparing HMs with the most common approaches used for modeling tick data (e.g., ANOVA), we show that population estimates are biased low for simulated and empirical data when using non-HMs, and that confounding occurs due to not explicitly modeling factors that influenced both detection and abundance. Our review and analysis of simulated and empirical data shows that it is important to account for our ability to detect ticks using field methods with imperfect detection. Not doing so leads to biased estimates of occurrence and abundance which could complicate our understanding of parasite-host relationships and the spread of tick-borne diseases. We highlight the resources available for learning HM approaches and applying them to analyzing tick data.
Schmidt, J.H., W.L. Thompson, T.L. Wilson, J.H. Reynolds. 2022. Understanding the impacts of the detection process on distance sampling surveys: selecting among approaches and minimizing total error. Wildlife Monographs 210: e1070. https://doi.org/10.1002/wmon.1070 \| Abstract	July 2022	Wildlife population estimators often require formal adjustment for imperfect detection of individuals during surveys. Conventional distance sampling (CDS) and its extensions (mark‐recapture distance sampling [MRDS], temporary emigration distance sampling [TEDS]) are popular approaches for producing unbiased estimators of wildlife abundance. However, despite extensive discussion and development of distance sampling theory in the literature, deciding which of these alternatives is most appropriate for a particular scenario can be confusing. Some of this confusion may stem from an incomplete understanding of how each approach addresses the components of the detection process. Here we describe the proper application of CDS, MRDS, and TEDS approaches and use applied examples to help clarify their differing assumptions with respect to the components of the detection process. To further aid the practitioner, we summarize the differences in a decision tree that can be used to identify cases where a more complex alternative (e.g., MRDS or TEDS) may be appropriate for a given survey application. Although the more complex approaches can account for additional sources of bias, in practical applications one also must consider estimator precision. Therefore, we also review the concept of total estimator error in the context of comparing competing methods for a given application to aid in the selection of the most appropriate distance sampling approach. Finally, we detail how the use of more advanced techniques (i.e., informed priors, open‐population distance sampling models, and integrated modeling approaches) can further reduce total estimator error by leveraging information from existing and ongoing data collection .By synthesizing the existing literature on CDS, MRDS, TEDS and their extensions, in conjunction with the concepts of total estimator error and the components of the detection process, we provide a comprehensive guide that can be used by the practitioner to more efficiently, effectively, and appropriately apply distance sampling in a variety of settings.
Berube, J., A.P.K. Sirén, B. Simpson, K.B. Klingler, T.L. Wilson. 2024. Monitoring off-host winter tick abundance on traditional moose hunting lands. Journal of Wildlife Management 88:e22630. DOI: 10.1002/jwmg.22630. \| Abstract \| Publisher Website	July 2024	An important symbolic and subsistence animal for many Native American Tribes, the moose (<i>Alces alces</i>; mos in Algonquin, Penobscot language) has been under consistent threat in the northeastern United States because of winter tick (<i>Dermacentor albipictus</i>) parasitism over the past several decades, causing declines in moose populations throughout the region. This decline has raised concern for Tribes and agencies that are invested in moose. Given this concern, it is increasingly important to effectively monitor and develop strategies to manage winter ticks to address consistent population declines of moose due to winter ticks. The Penobscot Nation developed a novel strategy to sample questing winter ticks (i.e., ticks that are actively seeking hosts) using a plot-based sampling protocol that may be suitable for heterogeneous habitats. We deployed this protocol in the northeastern United States in 2022 during the tick questing period (Sep–Dec) on Penobscot Nation sovereign trust lands, the White Mountain National Forest and Umbagog National Wildlife Refuge, and western-central Massachusetts, USA. We analyzed the data using occupancy and N-mixture models. Detection probability peaked during mid-October and tick occupancy and abundance were greatest at sites with intermediate understory vegetation height. The sampling protocol was successful at sampling ticks in Massachusetts, where abundances were expected to be low, indicating that it may be useful for studies planning to monitor winter tick distribution and abundance in areas with sub-optimal moose habitat and where winter tick abundance is expected to be low. This approach may also benefit managers or researchers intending to monitor many species of hard ticks, and where imperfect detection is expected.

Presentations

Presentations	Presentation Date
Wilson, T.L., J.A. Berube, A.P.K. Sirén. Perfecting the Imperfect Detection of Ticks: Winter Tick Epizootics and Moose Populations in the Northeastern U.S. Moose research in the Northeast U.S. and eastern provinces of Canada: 6 July 2022. On-line meeting.	July 2022
Wilson, T.L., A.P.K. Sirén, J. Berube, B. Simpson. A novel method for monitoring off-host winter ticks in habitat where detection and abundance are expected to be low. Workshop of moose research needs in the Northeast. Sherbrooke, QC, Canada. 13 December 2023.	December 2023
Wilson, T. L., J. Berube, A.P.K Sirén, B. Simpson, K. Klingler. Understanding drivers of winter tick (Dermacentor albipictus) abundance and distribution in New England. Asia-Pacific Wildlife Health Workshop, 6-8 August 2024. Hilo, HI.	August 2024
Sirén, A.P.K., T.L. Wilson, K.Dunfey-Ball, K.D. Gieder, C.A. Bernier, N.L. Fortin, T. Smith, J.R. Kilborn, C.B. Callahan, R.M. Cliché, L.S. Prout, S, Wixsom, S. Staats, R. Abrams, S. Gifford, R. K. Patry, L.E. Kantar, T.L. Morelli. Broad-scale climate and habitat influences winter tick-moose dynamics along trailing range edges. North American Moose Conference, Midway, UT, USA. 13-16 May 2024.	May 2024
Sirén, A.P.K., J. Clark, R.M. Cliché, C.B. Callahan, J.R. Kilborn, C.S. Bernier, K.D. Gieder, P.G. Jensen, R. Patry, L.S. Prout, S. Wixsom, S. Gifford, T.L. Morelli, T.L. Wilson. 2024. Form fits function: Matching camera trap protocols with research objectives. NEAFWA, Hyannis, MA. Invited Oral Presentation. 21-24 April 2024.	April 2024
Sirén A.P.K., T.L. Wilson, K. Dunfey-Ball, K.D. Gieder, C.A. Bernier, N.L. Fortin, T. Smith, J.R. Kilborn, C.B. Callahan, R.M. Cliché, L. S. Prout, S. Wixsom, S. Staats, R. Abrams, S. Gifford, R.K. Patry, L.E. Kantar, and T.L. Morelli. Broad scale climate and habitat drivers mediate occupancy-dependent parasitism along trailing range edges. Workshop on moose research needs in the Northeast. Sherbrooke, QC, Canada. 13 December 2023.	December 2023
Berube, J., A.P.K Sirén, B. Simpson, K. Klingler, T.L. Wilson. Moose’n around with ticks in New England. NEAFWA, Hyannis, MA. Contributed Oral Presentation. 21-24 April 2024.	April 2024
Berube, J., A. P. K. Sirén, C. Frank, L. Clarfeld, B. Simpson, T.M. Donovan, T. L. Wilson. 2022. Perfecting the Imperfect Detection of Ticks: Winter Tick Epizootics and Moose Populations in the Northeastern U.S. Presentation. The Wildlife Society Annual Conference, Spokane, WA. 6-10 November.	November 2022
Berube, J. APK Sirén, CF Sullivan, L Clarfeld, B Simpson, TL Wilson. 2023. A big little problem. Assessing winter tick epizootics and moose populations in the Northeastern US. Northeast Regional Native American Fish and Wildlife Society. 6-9 November.	November 2023

Cooperative Fish and Wildlife Research Units Program: Massachusetts Education, Research and Technical Assistance for Managing Our Natural Resources