Age-related variation in non-breeding foraging behaviour and carry-over effects on fitness in an extremely long-lived bird

1. Senescence has been widely documented in wild vertebrate populations, yet the proximate drivers of age-related declines in breeding success, including allocation trade-offs and links with foraging performance, are poorly understood. For long-lived, migratory species, the non-breeding period represents a critical time for investment in self-maintenance and restoration of body condition, which in many species is linked to fitness. However, the relationships between age, non-breeding foraging behaviour and fitness remain largely unexplored. 2. We performed a cross-sectional study, investigating age-related variation in the foraging activity, distribution and diet of an extremely long-lived seabird, the wandering albatross Diomedea exulans during the non-breeding period, and its links with subsequent reproductive performance. 3. We tracked the distributions of 82 adults aged 8 – 33 years with geolocator-immersion loggers and found an age-related decline in the number of landings (a proxy...1. 衰老是野生脊椎动物种群中已被广泛记录的生物学现象，但与年龄相关的繁殖成功率下降的近因驱动因素——包括资源分配权衡及其与觅食表现的关联——仍未得到充分阐明。对于长寿迁徙物种而言，非繁殖期是其投入自我维持、恢复身体状态的关键阶段，而在多数类群中，身体状态与进化适合度紧密相关。然而，年龄、非繁殖期觅食行为与适合度三者之间的关联，迄今仍鲜有研究探索。 2. 本研究采用横断面研究设计，针对一种超长寿命海鸟——漂泊信天翁（Diomedea exulans）——的非繁殖期觅食活动、分布范围与饮食结构的年龄相关变异，及其与后续繁殖表现的关联展开了系统性调查。 3. 研究团队借助地理定位浸入式记录仪（geolocator-immersion loggers），对82只年龄介于8至33岁的成年个体进行了分布追踪，结果发现个体着陆次数（一种替代指标……）呈现随年龄增长而下降的趋势。