Emslie Steven D, McKenzie Ashley, Patterson William P
Department of Biology and Marine Biology, University of North Carolina, 601 South College Road, Wilmington, NC 28403, USA.
Saskatchewan Isotope Laboratory, 114 Science Place, Saskatoon, Saskatchewan, Canada S7N 5E2.
R Soc Open Sci. 2018 Apr 18;5(4):172032. doi: 10.1098/rsos.172032. eCollection 2018 Apr.
We report new discoveries and radiocarbon dates on active and abandoned Adélie penguin () colonies at Cape Adare, Antarctica. This colony, first established at approximately 2000 BP (calendar years before present, i.e. 1950), is currently the largest for this species with approximately 338 000 breeding pairs, most located on low-lying Ridley Beach. We hypothesize that this colony first formed after fast ice began blocking open-water access by breeding penguins to the Scott Coast in the southern Ross Sea during a cooling period also at approximately 2000 BP. Our results suggest that the new colony at Cape Adare continued to grow, expanding to a large upper terrace above Ridley Beach, until it exceeded approximately 500 000 breeding pairs (a 'supercolony') by approximately 1200 BP. The high marine productivity associated with the Ross Sea polynya and continental shelf break supported this growth, but the colony collapsed to its present size for unknown reasons after approximately 1200 BP. Ridley Beach will probably be abandoned in the near future due to rising sea level in this region. We predict that penguins will retreat to higher elevations at Cape Adare and that the Scott Coast will be reoccupied by breeding penguins as fast ice continues to dissipate earlier each summer, restoring open-water access to beaches there.
我们报告了在南极洲阿代尔角活跃和废弃的阿德利企鹅（）栖息地的新发现及放射性碳年代测定结果。这个栖息地大约在距今2000年前（即公元1950年之前的历年）首次形成，目前是该物种最大的栖息地，约有33.8万对繁殖配偶，大部分位于地势低洼的里德利海滩。我们推测，这个栖息地最初形成于大约2000年前的一个寒冷时期，当时快速冰开始阻挡繁殖企鹅进入罗斯海南部斯科特海岸的开阔水域。我们的研究结果表明，阿代尔角的新栖息地持续增长，扩展到里德利海滩上方的一个大型上层阶地，直到大约公元1200年超过50万对繁殖配偶（一个“超级栖息地”）。与罗斯海冰间湖和大陆架断裂相关的高海洋生产力支持了这一增长，但该栖息地在大约公元1200年后因不明原因缩减至目前的规模。由于该地区海平面上升，里德利海滩可能在不久的将来被废弃。我们预测，企鹅将退回到阿代尔角海拔更高的地方，并且随着每年夏天快速冰持续更早消散，斯科特海岸将被繁殖企鹅重新占据，恢复那里海滩的开阔水域通道。
