Data from: Deceiving predators: linking distraction behavior with nest survival in a ground-nesting bird

Individual behavior that minimizes predation risk is favored by natural selection. Ground-nesting birds employ different defensive behaviors as part of their antipredator strategies because they nest where a wide range of predators have access. We investigated the influence of distraction displays on breeding success in the Kentish Plover, Charadrius alexandrinus, in order to explore the role of the defensive behavior on nest survival. We quantified the intensity of defensive behavior of adult plovers in response to nest disturbance caused by an approaching researcher, by ranking display types according to the intensity and exposure to predation. We also examined sex differences in nest defense to determine whether the existence, intensity, and consistency of individual defensive behaviors could have an impact on nest survival. We used the nest survival model in Program MARK to estimate daily survival rates of nests and to examine the influence of temporal, behavioral, and habitat variables on nest success. Our results show a positive correlation between male and female defense behaviors within pairs and that nests in which parents invested more on defense survived longer. Nevertheless, there were differences in the risks assumed by the 2 members of breeding pairs in nest defense, with females performing riskier defensive behaviors than males. The top-ranked nest survival models included combined additive effects of site, season, habitat type, nest exposure, and the defense behavioral response of females as best predictors. Finally, our study highlights that increased risk assumption in offspring defense is advantageous in terms of individual fitness.能够降低被捕食风险的个体行为，会受到自然选择的青睐。地面筑巢鸟类的巢址易被多种捕食者造访，因此它们会采用多种防御行为作为反捕食策略的组成部分。本研究以环颈鸻（Charadrius alexandrinus）为对象，探究干扰炫耀行为对其繁殖成功率的影响，以明确防御行为在巢窝存活中的作用。我们以接近巢区的研究者所引发的巢区干扰为刺激源，依据行为强度与被捕食暴露风险对防御炫耀行为类型进行分级，以此量化成年环颈鸻的防御行为强度。此外，我们还分析了巢防御行为中的性别差异，以探究个体防御行为的有无、强度与一致性是否会对巢窝存活产生影响。我们采用Program MARK软件中的巢存活模型估算巢的日存活概率，并分析了时间、行为及生境变量对繁殖成功率的影响。研究结果显示，配对繁殖的雌雄个体间防御行为呈正相关，且双亲投入更多防御行为的巢窝存活时间更长。尽管如此，繁殖配对的雌雄个体在巢防御中承担的风险存在差异，雌性所实施的防御行为比雄性更具风险性。最优拟合的巢存活模型将生境位点、繁殖季节、生境类型、巢区暴露程度以及雌性的防御行为响应作为最优预测因子，包含上述变量的联合加性效应。最后，本研究表明，在后代防御中承担更高风险，对个体适合度而言是有利的。