Are breeding activities risky for northern bobwhites? An assessment of survival costs of reproduction

Behaviors associated with breeding can increase mortality risk. This increased risk can be thought of as a cost of reproduction. Increased movements prior to breeding are common as individuals search for food and breeding sites. These increased movements are thought to entail greater predation risks as individuals travel through unfamiliar areas but few studies have looked at how these prebreeding movements affect survival, especially at a fine temporal resolution. Costs of reproduction may also occur during reproduction. For birds, incubation and brood-rearing can increase predation risk because individuals spend most of their time at nest sites or with broods, which may make them more easily detected and captured by predators. Using time- and individual-specific predictors of survival, I examined the relationship between survival, movements, habitat use, and breeding status of northern bobwhites Colinus virginianus in Colorado, USA. I found that prebreeding ranges were larger for bree..., Field crews captured bobwhites using baited walk-in traps (Smith et al. 1981) from February through May. We distributed traps throughout Tamarack to try to capture a spatially representative sample and checked traps twice daily (mid-morning and sunset). To reduce injury to captured quail, we used cloth mesh material (Hex mesh, Joanne Fabric) for the top of the trap (Stoddard 1931, Snyder 1978, Wiley et al. 2012). To maximize capture success, we scraped away litter underneath traps and covered traps with woody and herbaceous debris (Behney et al. 2020). Observers weighed all captured bobwhites using a Pesola 300 g spring scale, aged them as either juvenile (hatched previous year) or adult (hatched prior to previous year) based on primary coverts (Leopold 1939), and affixed a numbered, aluminum leg band (National Band & Tag Company, Newport, Kentucky, USA). We affixed a ≤ 6.5 g necklace-style VHF radio transmitter (Burger et al. 1995, DeMaso et al. 1997, 3.8% of average female mass (1...,