Data from: Extreme climate events and individual heterogeneity shape life history traits and population dynamics

The Southern fulmar is an ice-dependent seabird, and individuals forage near the ice edge. During an extreme unfavorable year -when sea ice area is reduced and the distance between the ice edge and the colony is high - observed foraging trips were greater in distance and duration. As a result, adults brought less food to their chicks, which fledged in the poorest body condition. During such unfavorable years, breeding success was extremely low, hence the population growth rate was greatly reduced. The opposite pattern occurred during extreme favorable years. Previous breeding status had a strong influence on life history traits and population dynamics, as well as their responses to extreme conditions. Successful breeders had a higher chance of breeding and raising their chick successfully during the following breeding season as compared to other breeding stages, regardless of environmental conditions. Consequently, they coped better with extreme unfavorable sea ice conditions. The effect of a change in successful breeder vital rates on population growth rate (λ) was greater than for other stages' vital rates, except for pre-breeder recruitment probabilities, which most affected λ. For environments characterized by ordinary sea-ice conditions, inter-individual differences were more likely to persist over the life of individuals and randomness in individual pathways was low suggesting an individual heterogeneity in vital rates arising from innate or acquired phenotypic traits. In addition, unfavorable ESIC tends to exacerbate individual differences in intrinsic quality, expressed through differences in reproductive status. We discuss the strong effects of ESIC on Southern fulmar life history traits in an evolutionary context. ESICs strongly affect fitness components and act as a potentially important agent of natural selection of life histories related to intrinsic quality and intermittent breeding. In addition, recruitment is a highly plastic trait that if heritable, could have critical role in the evolution of life histories. Finally, we find that changes in the frequency of extreme events may have a strong impact on the persistence of Southern fulmar population.

南管鼻藿（Southern fulmar）是一种依赖海冰的海鸟，个体多在冰缘附近觅食。在极端不利年份——当海冰面积缩减、冰缘与繁殖聚居地之间的距离增大时——观测到的觅食行程的距离与时长均有所增加。这导致成鸟向雏鸟递送的食物减少，雏鸟出飞时身体状况最差。此类不利年份的繁殖成功率极低，因此种群增长率大幅下降；极端有利年份则呈现相反的模式。过往的繁殖状态对生活史特征、种群动态及其对极端条件的响应均具有显著影响。相较于其他繁殖阶段，成功繁殖的个体在后续繁殖季中更有可能再次成功繁殖并抚育雏鸟，且不受环境条件的制约。因此，它们能更好地应对极端不利的海冰状况。成功繁殖个体的生命率变化对种群增长率（λ）的影响，大于其他阶段的生命率变化，但繁殖前个体的补充概率除外——后者对λ的影响最为显著。在以常规海冰状况为特征的环境中，个体间的差异更可能在个体一生中持续存在，且个体生存路径的随机性较低，这表明生命率的个体异质性源自先天或后天获得的表型性状。此外，不利的极端海冰状况（Extreme Sea Ice Conditions，下文简称ESIC）往往会加剧个体内在品质的差异，这种差异可通过繁殖状态的差异体现出来。我们从进化视角探讨了ESIC对南管鼻藿生活史特征的强烈影响。ESIC会显著影响适合度组分，并可作为与内在品质和间歇繁殖相关的生活史特征自然选择的潜在重要驱动力。此外，种群补充是一种高度可塑性的性状，若其可遗传，则可能在生活史进化中发挥关键作用。最后，我们发现极端事件发生频率的变化可能会对南管鼻藿种群的存续产生强烈影响。