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


Grisham, B.A., and C.W. Boal. 2015. Causes of Mortality and Temporal Patterns in Breeding Season Survival of Lesser Prairie-Chickens in Shinnery Oak Prairies. Wildlife Society Bulletin 39:536-542.

Abstract

ABSTRACT Baseline survival and mortality data for lesser prairie-chickens (Tympanuchus pallidicinctus) are lacking in shinnery oak (Quercus havardii) prairies, hampering sound conservation strategies for the species in the southern and western periphery of its range. This is especially relevant given reported differences in life history strategy for this species across its range and the current review of the species candidate status for protection under the United States Endangered Species Act. We investigated cause-specific mortality and male and female survival of lesser prairie-chickens during the breeding season (1 March – 31 August) of 2008–2011 in Cochran, Hockley, Terry, and Yoakum counties, Texas. We recorded 51 deaths (32 males, 19 females) of radio-tagged individuals and attributed the majority of male (28%) and females (40%) deaths to mammalian predators. The model averaged probability of a male lesser prairie-chicken surviving the duration of the breeding season was 0.57 (SE = 0.08; 95% CI: 0.40, 0.72); survival was most strongly influenced by the breeding season interval, with lower survival probabilities in June. The probability of a female lesser prairie-chicken surviving the breeding season varied among year and breeding season interval, but was lowest when hens were incubating nests. Overall, the probability of a female lesser prairie chicken surviving the breeding season was highest in 2010 (0.89; SE = 0.09; 95% CI: 0.53, 0.98) and lowest in 2011 2011 (0.71; SE = 0.14; 95% CI: 0.38, 0.90). Our results are consistent with previous studies that report mammals as the main predator on adult lesser prairie-chickens during the breeding season, and female mortalities are most frequent during nest incubation. Lastly, our data suggest survival during the breeding season is acceptable at current levels and therefore unlikely as a primary limiting demographic factor for lesser prairie-chickens in shinnery oak prairies.