Early nest initiation and vegetation density enhance nest survival in Wild Turkeys

The theory of adaptive habitat selection suggests resource selection by
animals should reflect underlying quality, such that individual selection
confers an adaptive advantage via increased fitness. Using resource
selection functions and nest survival models, we demonstrated that visual
obstruction at the nest site was adaptively significant but timing of nest
initiation had the greatest effect on nest survival for eastern wild
turkeys (Meleagris gallopavo silvestris). Predation risk is a selective
pressure, and if individuals can perceive predation risk, they may respond
by altering selection of nest site characteristics based on prior
experience. We evaluated patterns in nest site selection of 387 wild
turkeys and consequences of selection on reproductive success across the
southeastern United States from 2014-2019. We monitored 549 nest sites and
found that nest initiation date had the strongest effect on daily nest
survival rates, wherein adult females at our earliest nest initiation date
were ~ 4 times more likely to successfully nest than females at our latest
nest initiation dates. Selection of nest sites with greater visual
obstruction also increased daily nest survival rates as females were 1.17
(1.100 – 1.234; 95% CI) and 1.37 (1.258 – 1.486; 95% CI) times more likely
to select sites for every 10 cm increase in visual obstruction and maximum
vegetation height, respectively. Collectively, our results indicate that
nest initiation date is likely the critical parameter driving wild turkey
nest success, whereas vegetative conditions play a lesser role influencing
nest success. Females nesting earlier may be in better body condition and
show increased nest attentiveness, which may mediate nest success more
than vegetation conditions around nest sites. Our work indicates that
increasing the reproductive success of wild turkeys may hinge on females
being able to nest as early as possible within the reproductive season.