Institut de Recerca de la Biodiversitat (IRBio) and Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals (BEECA), Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain.
iMARES group, Departament de Recursos Marins Renovables, Institut de Ciències del Mar (ICM-CSIC), Barcelona, Spain.
Glob Chang Biol. 2024 Mar;30(3):e17191. doi: 10.1111/gcb.17191.
The response to climate change in highly dimorphic species can be hindered by differences between sexes in habitat preferences and movement patterns. The Antarctic fur seal, Arctocephalus gazella, is the most abundant pinniped in the Southern Hemisphere, and one of the main consumers of Antarctic krill, Euphausia superba, in the Southern Ocean. However, the populations breeding in the Atlantic Southern Ocean are decreasing, partly due to global warming. Male and female Antarctic fur seals differ greatly in body size and foraging ecology, and little is known about their sex-specific responses to climate change. We used satellite tracking data and Earth System Models to predict changes in habitat suitability for male and female Antarctic fur seals from the Western Antarctic Peninsula under different climate change scenarios. Under the most extreme scenario (SSP5-8.5; global average temperature +4.4°C projected by 2100), suitable habitat patches will shift southward during the non-breeding season, leading to a minor overall habitat loss. The impact will be more pronounced for females than for males. The reduction of winter foraging grounds might decrease the survival of post-weaned females, reducing recruitment and jeopardizing population viability. During the breeding season, when males fast on land, suitable foraging grounds for females off the South Shetland Islands will remain largely unmodified, and new ones will emerge in the Bellingshausen Sea. As Antarctic fur seals are income breeders, the foraging grounds of females should be reasonably close to the breeding colony. As a result, the new suitable foraging grounds will be useful for females only if nearby beaches currently covered by sea ice emerge by the end of the century. Furthermore, the colonization of these new, ice-free breeding locations might be limited by strong female philopatry. These results should be considered when managing the fisheries of Antarctic krill in the Southern Ocean.
气候变化对高度二态性物种的影响可能会受到性别间生境偏好和移动模式差异的阻碍。南极软毛海豹（Arctocephalus gazella）是南半球数量最多的鳍足类动物，也是南大洋南极磷虾（Euphausia superba）的主要消费者之一。然而，在南大洋繁殖的南极软毛海豹数量正在减少，部分原因是全球变暖。雄性和雌性南极软毛海豹在体型和觅食生态学上有很大的差异，它们对气候变化的性别特异性反应知之甚少。我们使用卫星跟踪数据和地球系统模型，预测了在不同气候变化情景下，来自西南极半岛的雄性和雌性南极软毛海豹在非繁殖季节的栖息地适宜性变化。在最极端的情景下（SSP5-8.5；到 2100 年全球平均气温预计上升 4.4°C），非繁殖季节适宜的栖息地斑块将向南移动，导致整体栖息地略有减少。这种影响对雌性的影响将比雄性更为明显。冬季觅食地的减少可能会降低已断奶雌性的存活率，减少繁殖率，并危及种群的生存能力。在繁殖季节，当雄性在陆地上禁食时，南设得兰群岛附近的雌性适宜觅食地将基本保持不变，而在别林斯高晋海将出现新的觅食地。由于南极软毛海豹是按收入繁殖的，因此雌性的觅食地应该离繁殖地相当近。因此，只有在本世纪末，目前被海冰覆盖的海滩出现时，这些新的适宜觅食地对雌性才会有用。此外，这些新的无冰繁殖地的殖民化可能会受到强烈的雌性恋地性的限制。在管理南大洋南极磷虾渔业时，应该考虑到这些结果。
