Lagged response of Adélie penguin ( Pygoscelis adeliae ) abundance to environmental variability in the Ross Sea, Antarctica

Environmental variability drives Adelie penguin (Pygoscelis adeliae) population dynamics through its effects on vital rates (e.g., survival, dispersal, or breeding success) resulted in penguin abundance changes with time delays. The lagged effects of environmental changes on penguin abundance are still not well defined. We divided the Ross Sea region into six areas to investigate the effects of environmental changes on penguin abundance from 1982 to 2013. Time lagged analysis of 1–6 years between penguin abundance and environmental factors were conducted in our study. We found that penguin abundance was significantly correlated with environmental factors at different lag times (p < 0.05). The relationship between penguin abundance and environmental factors might differ among regions. Generalized additive model results showed that sea surface temperature negatively affected penguin abundance in most regions of the Ross Sea. In mid-Victoria Land, the relationship between sea-ice concentration and penguin abundance was quadratic. Penguin abundance peaked when sea-ice concentration was approximately 40%. Optimal ranges of environmental factors for Adelie penguin population might exist. Our study highlighted the lagged response of penguin abundance to environmental factors to further understand the effects of climate changes on the Antarctic biosphere.