Northern bobwhite habitat use in a food subsidized pyric landscape

Abstract

Animals inhabiting disturbance-prone systems, such as the northern bobwhites (Colinus virginianus) in pine (Pinus spp.) savanna, are adapted to certain intensities of disturbance (e.g., frequency, spatial extent, seasonality). Management practices attempt to mimic these natural conditions. Even though northern bobwhites are known as the firebird, most fire-related management is currently based on tradition and limited peer-reviewed literature. We studied habitat selection of northern bobwhites on private property in Georgetown County, South Carolina, USA, managed with fire, winter disking, and supplemental feeding. We radio-tagged 338 individual bobwhites and monitored them 3-4 times weekly via very high frequency (VHF) telemetry for 2 years. We used hierarchical habitat selection functions in a Bayesian framework to model the data. We considered 2 spatial scales: the study site (second-order) and within home ranges (third-order). Bobwhites selected for small burns during the breeding season but had the highest selection for areas intermediately distant from burn edges during winter (i.e., 67 m). Bobwhites had the strongest selection for fire return intervals of 2-3 years during winter but 1-2 years during the breeding season. Use of supplemental feed was strong across seasons but not selected for by brooding birds within their home range. Use of fallow fields was strongest for brooding birds. Our results are useful for bobwhite managers, especially those in subtropical climates, because they provide scientifically defensible information supporting the use of prescribed fire, winter disking, and supplemental feeding in the context of habitat use. Ó 2017 The Wildlife Society.KEY WORDS Colinus virginianus, habitat use, home range, northern bobwhite, prescribed burning, radio-telemetry, supplemental feeding, winter disking.

Landscape Connectivity Influences Survival and Resource Use following Long‐Distance Translocation of Northern Bobwhite

“…Habitat selection varied based on landscape and scale of analysis and was generally in agreement with previous bobwhite research (Best et al 1997, Riffell et al 2008, Collins et al 2009, Janke and Gates 2013, McGrath et al 2017). Food and cover plantings and early‐succession woody vegetation provide forage resources and protective cover for bobwhites from natural predators.…”

“…We estimated breeding season (1 Apr–30 Sep) home ranges for all individuals with ≥25 telemetry locations (Terhune et al 2006 a , 2010; Singh et al 2011, McGrath et al 2017) using 50% and 95% fixed kernel density estimators (KDE) and 95% minimum convex polygons (MCP; Worton 1989, White and Garrott 1990) via the ADEHABITAT package (Calenge 2006) in R. We used this minimum telemetry location threshold to account for individual variation and reduce bias in home range estimates (White and Garrott 1990, Seaman et al 1999, Kenward 2001, Haines et al 2009). We estimated the smoothing parameter ( h ) for KDEs using the least‐squares cross validation (LSCV; Seaman and Powell 1996, Kenward 2001) procedure for each year and site.…”

“…For example, bobwhites have declined at an estimated rate of 11.5%/year in New Jersey and 9.5%/year in Maryland from 1966-2015, compared to a range-wide decline of 3.5%/year over that time frame (Sauer et al 2017). Furthermore, an accelerated decline since the 1980s has led to the functional extirpation of wild populations in New Jersey (Chanda et al 2011) and Pennsylvania, USA (McKenzie et al 2015, Martin et al 2017, 2 of the most-recent states to receive this designation.…”

Northern bobwhite foraging response to hunting

“…Therefore, we conducted a study to quantify the influences of risk from hunters using pointing dogs on foraging behavior on the northern bobwhite ( Colinus virginianus ; bobwhite). Common management practices include prescribed burning, seasonal disking, and supplemental feeding (McGrath et al ). However, these areas of supplemental feed often become targeted areas for hunters, creating a direct spatial overlap of high food availability and high risk levels (Brennan et al , Burger et al ).…”

Vegetation and predator interactions affect northern bobwhite behavior

“…Habitat may affect a prey animal's assessment of predation risk and their avoidance behavior such that energetically costly behaviors (e.g., flight) are reserved for only those situations of imminent threat (Whittingham et al , Stears and Shrader ). Supplemental feeding of prey may alter habitat directly by increasing food availability (Brown , Whittingham et al ), which influences game bird resource use (McGrath et al ).…”