Department of Bioscience, Aarhus University, Frederiksborgvej 399, 4000, Roskilde, Denmark.
Arctic Research Centre, Aarhus University, Ny Munkegade 116, 8000, Aarhus C, Denmark.
Oecologia. 2021 Apr;195(4):927-935. doi: 10.1007/s00442-021-04882-2. Epub 2021 Feb 20.
Habitat selection is expected to balance benefits and costs that maximizes fitness. Using a rare data set on collared lemming (Dicrostonyx groenlandicus) winter nest location spanning more than two decades, we show that lemmings actively select for Salix snow beds, likely due to its favorable micro-climate, and that lemming habitat selection was density-dependent. Lemmings nevertheless exhibited some flexibility in their habitat selection, which appeared to be influenced by the year-to-year variation in snow conditions. The likelihood of both lemming breeding and nest predation by stoats (Mustela erminea) was not directly linked to habitat despite a delicate interplay between habitat, nest size, breeding, and predation. Hence, the larger lemming nests were found in Salix snow beds, and these were more often used for breeding, but both larger nests and nests used for breeding were also predated more often than other nests. Our study provides a clear example of how density-dependent habitat selection acts to balance fitness in the various habitats utilized by collared lemmings.
栖息地选择旨在平衡收益和成本，以最大限度地提高适应性。我们利用一个跨越二十多年的罕见的环颈旅鼠冬季巢位数据，表明旅鼠积极选择柳雪床，可能是因为其有利的小气候，并且旅鼠的栖息地选择是密度依赖的。然而，旅鼠在其栖息地选择上表现出一定的灵活性，这似乎受到了每年雪况变化的影响。尽管栖息地、巢大小、繁殖和捕食之间存在微妙的相互作用，但旅鼠的繁殖和白鼬（Mustela erminea）对巢的捕食的可能性与栖息地并没有直接联系。因此，较大的旅鼠巢位于柳雪床上，并且这些巢更多地用于繁殖，但较大的巢和用于繁殖的巢比其他巢更容易受到捕食。我们的研究提供了一个清晰的例子，说明密度依赖的栖息地选择如何在环颈旅鼠利用的各种栖息地中平衡适应性。
