Habitat‐specific behavior, growth rate, and survival of piping plover chicks in New Jersey, USA

Abstract

Anthropogenic disturbance has been demonstrated to affect the behavior of beach-nesting birds, yet the energetic consequences of recreational activities have received less attention. Because precocial chicks are often displaced as a result of disturbance events, lower access to food may lead to lower fitness. We studied the influence of site characteristics and human disturbance on behavior, habitat use, growth rate, and survival of piping plover chicks in New Jersey, a portion of the Atlantic Coast population that continues to demonstrate poor demographic output. Sites varied in levels of human disturbance and access to high-quality foraging habitat, which are two critical components of fledging success. We found that compared to chicks with access to bayside foraging habitat, chicks at sites without such access experienced higher rates of anthropogenic disturbance, spent less time in moist-substrate habitats, and spent more time in upland dunes. Foraging rates were greatest for chicks in moist-substrate habitat with bayside access and for chicks in the oceanside intertidal zone without bayside access. Further, overall chick growth rates were higher for chicks reared at sites with bayside access. Chick survival increased with age, decreased with increasing precipitation, and increased with bayside foraging habitat availability. Human disturbance was likely limiting chick access to foraging opportunities at sites open to the public, with an apparent effect on growth rate. Maintaining access to high-quality foraging habitat that is free of human activity through habitat restoration, supplementary food, or beach closures could help to increase reproductive success in New Jersey.

Piping plover chick ecology following landscape‐level disturbance

“…In Rhode Island, USA, however, broods in mudflats spent less time disturbed (Goldin and Regosin 1998). In New Jersey, USA, moist foraging habitats were the least disturbed (Stantial et al 2021), and adult plover vigilance was related to the number of people on the beach, regardless of cover type (Burger 1994). In our same study area, foraging rate and the proportion of time spent in moist substrates were lower on days with typically higher disturbance (DeRose‐Wilson et al 2018).…”

“…access to habitat have higher survival (Stantial et al 2021). Rather than the distance to a resource, likely the more important factor for survival is whether a brood is spending time in moist areas with low wave energy.…”

“…Furthermore, adult survival likely is driven by flyway-wide conditions, making it challenging to evaluate the effect on survival in local conditions (Norris 2005;Gratto-Trevor et al 2012;Gibson et al 2018Gibson et al , 2019Weithman et al 2018). Alternatively, variation in chick behavior and survival primarily are driven by local characteristics and therefore are more manageable on the breeding grounds (Haffner et al 2009, Anteau et al 2014, Stantial et al 2021. Further, the chick-rearing period drives reproductive output and influences population growth, and therefore more study is warranted (USFWS 1985).…”

“…Declines in habitat also can reduce the effectiveness of camouflage and increase detection by predators, which may interact with density if predators develop an improved search image of local prey (Gendron and Staddon 1983). Increased human disturbance also may isolate and reduce available habitat if it is made unavailable or unsuitable by temporary obstruction (e.g., beach bathing) or by direct effects on habitat (e.g., rutting from beach driving; DeRose‐Wilson et al 2018, Walker et al 2019, Stantial et al 2021). Evaluating whether plover chick habitat selection changes through time following a landscape‐scale disturbance can advance the understanding of which factors are most important for improving reproductive output.…”

“…Like survival, plover behavior frequently has been studied, but habitat characteristics have primarily been assessed at a categorical level (e.g., high vs. low disturbance, wet vs. dry). Behavior is related to human disturbance (Burger 1994, DeRose‐Wilson et al 2018), and habitat (Loegering and Fraser 1995, Goldin and Regosin 1998, Elias et al 2000, Le Fer et al 2008 a , Stantial et al 2021), with researchers reporting that plovers respond to and avoid areas with frequent human disturbance and spend more time foraging in moist areas with low wave energy where invertebrates are abundant. Like selection and survival, an improved understanding of plover behavior may benefit from finer scale, spatially explicit analyses.…”