Breeding season survival of female Rio Grande wild turkeys in south‐central Texas

Abstract

AbstractHistorically, Rio Grande wild turkey (Meleagris gallopavo intermedia) density in south‐central Texas has been lower than other regions within the species' Texas range. Within the Oak‐Prairie Wildlife District of Texas, Rio Grande wild turkey harvest regulations are more restrictive for counties in the eastern portion of the district. Due to a perceived increase in turkey density in the eastern portion of the district, Texas Parks and Wildlife Department (TPWD) has considered increasing the spring hunting season harvest bag limit. Because estimates of sex‐specific abundance and male harvest rates are not available, estimates of female driven population parameters such and nest success and female survival can be used to support regulatory decision‐making. Therefore, before a regulation change we evaluated survival of radio‐marked female Rio Grande wild turkeys during the breeding season in 4 counties in the Special 1‐Male zone (hereafter 1‐bird zone) and 2 counties in the South zone (hereafter 4‐bird zone). We captured and monitored breeding season survival for 138 females during 2016–2018, of which 51 were in the 4‐bird zone and 87 were in the 1‐bird zone. Breeding season (1 Mar–14 Aug) naive mortality rate was 23% (19/81) of tagged females in the 1‐bird zone and 32% (14/43) in the 4‐bird zone. The best approximating candidate model for breeding season survival indicated variation in daily survival () was primarily related to daily distance of individual movements ( = 0.998 at average daily distance of 2,471 m). Estimated breeding season survival at the mean daily movement distance was 81% for the 167‐day period. Breeding season survival was similar between the 1‐bird and 4‐bird regulatory zone. Based on our results, female breeding season survival does not seem to be a limiting factor within the Oak‐Prairie Wildlife District of Texas for Rio Grande wild turkeys. We suggest that TPWD focus efforts on supporting landowners to enhance conditions more conducive for reproductive success and suggest future efforts focus on collection of harvest and harvest rate data to estimate population size in lieu of continued monitoring of female reproductive or survival parameters for decision processes.