Department of Zoology, University of Oxford, Oxford, United Kingdom.
Department of Environment, Australian Antarctic Division, Channel Hwy, Kingston, Tasmania, Australia.
PLoS One. 2018 Mar 21;13(3):e0193532. doi: 10.1371/journal.pone.0193532. eCollection 2018.
Polar seabirds adopt different over-wintering strategies to survive and build condition during the critical winter period. Penguin species either reside at the colony during the winter months or migrate long distances. Tracking studies and survey methods have revealed differences in winter migration routes among penguin species and colonies, dependent on both biotic and abiotic factors present. However, scan sampling methods are rarely used to reveal non-breeding behaviors during winter and little is known about presence at the colony site over this period. Here we show that Adélie penguins on the Yalour Islands in the Western Antarctic Peninsula (WAP) are present year-round at the colony and undergo a mid-winter peak in abundance during winter. We found a negative relationship between daylight hours and penguin abundance when either open water or compact ice conditions were present, suggesting that penguins return to the breeding colony when visibility is lowest for at-sea foraging and when either extreme low or high levels of sea ice exist offshore. In contrast, Adélie penguins breeding in East Antarctica were not observed at the colonies during winter, suggesting that Adélie penguins undergo differential winter strategies in the marginal ice zone on the WAP compared to those in East Antarctica. These results demonstrate that cameras can successfully monitor wildlife year-round in areas that are largely inaccessible during winter.
极地海鸟采取不同的越冬策略来生存，并在关键的冬季期间建立条件。企鹅物种要么在冬季留在聚居地，要么迁徙很远的距离。跟踪研究和调查方法揭示了不同企鹅物种和聚居地之间冬季迁徙路线的差异，这取决于存在的生物和非生物因素。然而，扫描采样方法很少用于揭示冬季的非繁殖行为，并且对这段时间聚居地的存在知之甚少。在这里，我们表明，位于南极半岛西部（WAP）的亚尔洛尔群岛上的阿德利企鹅全年都留在聚居地，并且在冬季会出现丰度的中期峰值。我们发现，当存在开阔水域或密集冰区时，白天时间与企鹅数量之间存在负相关关系，这表明当海上觅食的能见度最低时，或者当海上冰的极端低或高水平存在时，企鹅会返回繁殖地。相比之下，在冬季，我们没有在东部南极洲的聚居地观察到阿德利企鹅，这表明与东部南极洲相比，在 WAP 的边缘冰区，阿德利企鹅采取了不同的冬季策略。这些结果表明，在冬季大部分无法进入的地区，摄像机可以成功地全年监测野生动物。
