Department of Vertebrate Ecology and Zoology, Faculty of Biology, The University of Gdańsk, Gdańsk, Poland.
Department of Vertebrate Ecology and Zoology, Faculty of Biology, The University of Gdańsk, Gdańsk, Poland.
Sci Total Environ. 2022 Feb 20;808:152167. doi: 10.1016/j.scitotenv.2021.152167. Epub 2021 Dec 5.
The little auk Alle alle is an Arctic seabird breeding in the North Atlantic. Its southernmost breeding population in the Low Arctic occurred in Iceland but started to decline in numbers at the beginning of the 20th century ending in extirpation at the end of the same century. Climate warming has been blamed for the disappearance of this population. However, it was also exploited by humans (mainly for eggs). Thus, it is unclear what was the main driver for the population collapse. In this study, we reconstruct population dynamics in relation to changes in environmental conditions, and perform stochastic modelling of population viability considering various scenarios including presence/absence of climate warming and/or egg harvest. We found that extirpation of the studied population was attributed to synergistic effects of both climate warming and human harvest. The simulations revealed that climate warming without harvest would cause a 71% decline in population size but not lead to extirpation. Models with climate warming and egg harvesting resulted in population estimates close to the real data (decrease from 400 individuals in 1903 to 2 in 1996). This is one of the few studies documenting synergistic effect of climate warming and human exploitation on extirpation. A strong harvesting component in the explanation for the decline of the study population emphasizes the continuing need to control commercial harvest of animal species in the face of other pressures such as climate warming.
北极海雀 Alle alle 是一种生活在北大西洋的北极海鸟，其在北极圈南部的繁殖地位于冰岛，但从 20 世纪初开始，其数量开始减少，最终在本世纪末灭绝。气候变化被认为是导致该种群消失的原因。然而，人类也对其进行了开发利用（主要是为了获取其蛋）。因此，目前尚不清楚种群数量减少的主要原因是什么。在这项研究中，我们重建了与环境变化相关的种群动态，并考虑了各种情景（包括是否存在气候变暖以及是否存在蛋的采集）对种群生存能力进行了随机模型模拟。研究结果表明，该研究种群的灭绝归因于气候变暖与人类采集的协同作用。模拟结果显示，没有采集活动的气候变暖只会导致种群数量减少 71%，但不会导致灭绝。而同时存在气候变暖与蛋采集的模型则得出了与实际数据相近的种群估计值（从 1903 年的 400 只减少到 1996 年的 2 只）。这是少数几篇记录气候变暖与人类开发利用协同作用导致灭绝的研究之一。在解释研究种群数量下降的原因时，人类采集活动是一个重要因素，这强调了在面临其他压力（如气候变暖）的情况下，继续控制对动物物种的商业性采集的必要性。
