Département de biologie, chimie et géographie & Centre d'études nordiques, Université du Québec à Rimouski, Rimouski, G5L 3A1, Canada.
Norwegian Polar Institute, Fram Centre, Tromsø, 9296, Norway.
Sci Rep. 2021 Nov 11;11(1):22109. doi: 10.1038/s41598-021-01404-1.
In colonially breeding marine predators, individual movements and colonial segregation are influenced by seascape characteristics. Tidewater glacier fronts are important features of the Arctic seascape and are often described as foraging hotspots. Albeit their documented importance for wildlife, little is known about their structuring effect on Arctic predator movements and space use. In this study, we tested the hypothesis that tidewater glacier fronts can influence marine bird foraging patterns and drive spatial segregation among adjacent colonies. We analysed movements of black-legged kittiwakes (Rissa tridactyla) in a glacial fjord by tracking breeding individuals from five colonies. Although breeding kittiwakes were observed to travel up to ca. 280 km from the colony, individuals were more likely to use glacier fronts located closer to their colony and rarely used glacier fronts located farther away than 18 km. Such variation in the use of glacier fronts created fine-scale spatial segregation among the four closest (ca. 7 km distance on average) kittiwake colonies. Overall, our results support the hypothesis that spatially predictable foraging patches like glacier fronts can have strong structuring effects on predator movements and can modulate the magnitude of intercolonial spatial segregation in central-place foragers.
在殖民地繁殖的海洋捕食者中，个体运动和群体隔离受到景观特征的影响。潮汐冰川前缘是北极景观的重要特征，通常被描述为觅食热点。尽管它们对野生动物的重要性已被记录在案，但对于它们对北极捕食者运动和空间利用的结构影响却知之甚少。在这项研究中，我们检验了以下假设：潮汐冰川前缘可以影响海鸟觅食模式，并驱动相邻群体之间的空间隔离。我们通过跟踪来自五个繁殖地的繁殖个体来分析黑腿海鸥（Rissa tridactyla）在冰川峡湾中的运动。尽管观察到繁殖的黑腿海鸥可以从繁殖地旅行长达约 280 公里，但它们更有可能使用距离其繁殖地更近的冰川前缘，而很少使用距离其繁殖地超过 18 公里的冰川前缘。这种冰川前缘使用的变化在四个最接近的（平均约 7 公里距离）黑腿海鸥繁殖地之间产生了精细的空间隔离。总的来说，我们的结果支持这样的假设，即像冰川前缘这样空间可预测的觅食斑块可以对捕食者的运动产生强烈的结构影响，并调节中央觅食者之间的殖民地间空间隔离的程度。
