Using statistical population reconstruction to estimate demographics of wild turkey populations

Abstract

Although the wild turkey (Meleagris gallopavo; hereafter, turkey) is one of the most popular game species in the United States, there is no consensus on how best to monitor turkey populations. Harvest data are readily available to state wildlife agencies but are often not coupled with other datasets (e.g., hunter effort) for demographic assessments. We described the utility of statistical population reconstruction (SPR) to unite disparate datasets and effectively monitor status and trends of key turkey demographic rates at spatial scales relevant to wildlife managers. We demonstrated SPR model development and associated assumptions, model selection, and model evaluation using male‐only models for turkeys in 2 regions of Missouri, USA, and compared model output to harvest‐based and non‐harvest‐based indices. Use of SPR led to a more comprehensive assessment of population dynamics than did indices alone. Moreover, inference based solely on indices would likely have led to different interpretations of which factors govern turkey population dynamics and ultimately which management practices should be implemented. Disparity of model output between regions demonstrates importance of auxiliary data in SPR model utility. As such, we encourage well‐planned and executed auxiliary studies to improve precision of demographic rates when using SPR models. Statistical population reconstruction provides a viable, useful tool to assess demographics of turkey populations and on which to base management decisions.

Review of range‐wide vital rates quantifies eastern wild Turkey population trajectory

“…A critical evaluation of new and existing techniques for monitoring these periods should be a high priority so that researchers can make more informed decisions when designing studies on these periods. As an alternative to directly monitoring survival, use of quantitative methods, such as integrated population models or statistical population reconstruction (Ahrestani et al, 2017 ; Clawson et al, 2022 ; McConnell et al, 2018 ), may allow for the estimation of information about these missing life stages or alternative parameters such as recruitment. Use of parameters like recruitment is not perfect substitution for directly monitoring poult or youth survival, as the use of these metrics can mask variation in stage‐specific survival, but these approaches may help fill the gaps in our knowledge of these difficult‐to‐study life stages (McConnell et al, 2018 ).…”

Survival, harvest, and population size of Rio Grande wild turkeys in Texas

“…Yet, to date, none of these approaches have been applied for estimating turkey population size in Texas. Our use of banded wild turkeys and reported hunter harvested wild turkeys provides a data-driven population estimate, similar to work by Diefenbach et al (2012) that directly estimates population size without the need for ancillary data collection or strong statistical assumptions (Gast et al 2013, Clawson et al 2022).…”

“…For wild turkeys, use of harvest information can be integrated with ancillary data to provide long‐term population trends (Diefenbach et al 2012, Alisauskas et al 2014, Seamans and Braun 2016), which can guide harvest management recommendations. Information provided using band recovery approaches to monitor wild turkey population size provides clear advantages, including incorporation of harvest data and estimation of population parameters such as age‐ and sex‐specific survival, relative to other population monitoring approaches (Butler et al 2007 b ) or population reconstruction methods (Gast et al 2013, Clawson et al 2022). For example, harvest rates in conjunction with estimates of harvest have been used to estimate eastern wild turkey ( M. g. silvestris ) abundance across 3 states in the northeastern United States (Diefenbach et al 2012).…”