Individual variation in winter supplementary food consumption and its consequences for reproduction in wild birds.

The provision of wild birds with supplementary food has increased substantially over recent decades. While it is assumed that provisioning birds is beneficial, supplementary feeding can have detrimental ‘carry-over’ effects on reproductive traits. Due to difficulties in monitoring individual feeding behaviour, assessing how individuals within a population vary in their exploitation of supplementary food resources has been limited. Quantifying individual consumption of supplementary food is necessary to understand the operation of carry-over effects at the individual level. We used Radio Frequency Identification (RFID) technology and automated feeders to estimate individual consumption of supplementary winter food in a large wild population of great tits Parus major and blue tits Cyanistes caeruleus. Using these data, we identified demographic factors that explained individual variation in levels of supplementary food consumption. We also tested for carry-over effects of supplementary fo...近几十年来，为野生鸟类提供补充食物的行为已大幅增加。尽管普遍认为投喂鸟类对其有益，但补充喂食可能会对繁殖性状产生有害的"遗留效应（carry-over effects）"。由于监测个体取食行为存在难度，评估种群内个体对补充食物资源的利用程度差异始终受到限制。若要在个体层面厘清遗留效应的作用机制，量化个体对补充食物的消耗量是必要前提。我们采用射频识别（Radio Frequency Identification, RFID）技术与自动喂食器，对大山雀（Parus major）和蓝山雀（Cyanistes caeruleus）的大型野生种群的冬季补充食物个体消耗量进行了估算。基于上述监测数据，我们识别出了能够解释补充食物消耗量个体差异的种群统计学因素；同时还检验了补充食物的……