Eastern wild turkey nest site selection in two frequently burned pine savannas

Abstract

Introduction: Reproductive success is a critical factor affecting avian demographics and can be influenced by many factors including nesting chronology, predation risk, and fine-scale nest site selection. Methods:We modeled the relative influences of habitat-related covariates at six spatial scales (nest site: 15-, 40-, 80-, 120-, 160-, and 200-m radii) on Eastern wild turkey (Meleagris gallopavo silvestris) nest site selection in two pine savannas managed by frequent prescribed fire (≤3 years) in southwestern Georgia during 2011-2013.Results: Nest site (15-m scale) habitat metrics (mean visual obstruction [cm] and canopy closure [%]) had the greatest influence on nest site selection relative to covariates measured at larger spatial scales. Scaled odds ratios suggested that nests were 26.8 % more likely to occur for every 10 cm increase in mean vegetation height with a range of 7.5 to 150.0 cm and 18.5 % less likely to occur for every 10 % increase in canopy closure with a range from 0.0 to 97.8 %. Total ground cover, canopy closure, edge density, and percent land cover type (e.g., mature pine, mixed pine/hardwood, shrub/scrub) had minimal influence on nest site selection.Conclusions: Management of pine savannas for turkey nest sites should focus on creating early-successional vegetation to conceal nests from potential predators. Additionally, we suggest that future studies consider evaluating the influence of spatial scale on turkey nest site selection.

Nest site selection and nest survival of eastern wild turkeys in a pyric landscape

“…This is not surprising because most previous researchers evaluating vegetation conditions reported nest selection to be positively associated with percent ground cover or density of ground story vegetation (Chamberlain and Leopold , Byrne and Chamberlain , Fuller et al , Kilburg et al , Streich et al ). Conversely, visual obstruction at the nest was not an important predictor of nest site selection, contrary to several recent studies (Byrne and Chamberlain , Streich et al , Little et al ). In the closed canopy bottomland forests studied by Byrne and Chamberlain (), understory vegetation was reportedly sparse and limited availability of nesting cover.…”

“…This approach allowed us to use model comparison and selection in an information‐theoretic framework (Burnham and Anderson ). Similar to Little et al (), we calculated Pearson's correlations ( r ) between explanatory variables at each scale prior to building our models. Because highly correlated variables (| r | ≥ 0.7) included in the same model inflate estimates of variance and hinder biologically relevant interpretation of data, we only retained the variable that provided the simplest biological interpretation (Dormann et al ).…”

“…This approach allowed us to use model comparison and selection in an informationtheoretic framework (Burnham and Anderson 2002). Similar to Little et al (2016), we calculated Pearson's correlations (r) between explanatory variables at each scale prior to building our models. Because highly correlated variables (|r| !…”

Nest and brood site selection of eastern wild turkeys

“…We based 4 models on the prediction that selection was influenced by ground cover, visual obstruction, canopy closure, or basal area. Ground cover influences selection of nests (Badyaev , Fuller et al , Yeldell et al ), as does visual obstruction (Holbrook et al , Streich et al , Little et al ). Ideal habitat for broods should provide adequate concealment for poults while providing females unobstructed views to detect predators (Porter ).…”

“…Vegetation cover surrounding nest sites may be an important cue to turkeys when selecting nest sites (Conley et al 2016, Little et al 2016. Turkeys select nests in areas with relatively dense vegetation and visual obstruction (Porter 1992, Badyaev 1995, Streich et al 2015, Yeldell et al 2017a.…”