Enari Hiroto, Enari Haruka S, Sekiguchi Tatsuhito, Tanaka Motohisa, Suzuki Sohsuke
Faculty of Agriculture, Yamagata University, 1-23 Wakabamachi, Tsuruoka, Yamagata, 997-8555, Japan.
Front Zool. 2024 Feb 1;21(1):3. doi: 10.1186/s12983-024-00522-6.
Recent climate changes have produced extreme climate events. This study focused on extreme snowfall and intended to discuss the vulnerability of temperate mammals against it through interspecies comparisons of spatial niches in northern Japan. We constructed niche models for seven non-hibernating species through wide-scaled snow tracking on skis, whose total survey length was 1144 km.
We detected a low correlation (r < 0.4) between most pairs of species niches, indicating that most species possessed different overwintering tactics. A morphological advantage in locomotion cost on snow did not always expand niche breadth. In contrast, a spatial niche could respond to (1) drastic landscape change by a diminishing understory due to snow, possibly leading to changes in predator-prey interactions, and (2) the mass of cold air, affecting thermoregulatory cost and food accessibility. When extraordinary snowfall occurred, the nonarboreal species with larger body sizes could niche shift, whereas the smaller-sized or semi-arboreal mammals did not. In addition, compared to omnivores, herbivores were prone to severe restriction of niche breadth due to a reduction in food accessibility under extreme climates.
Dietary habits and body size could determine the redundancy of niche width, which may govern robustness/vulnerability to extreme snowfall events.
近期气候变化引发了极端气候事件。本研究聚焦于极端降雪，并试图通过对日本北部地区温带哺乳动物空间生态位的种间比较，探讨它们对极端降雪的脆弱性。我们通过在滑雪板上进行大规模的积雪追踪，为7种非冬眠物种构建了生态位模型，总调查长度达1144公里。
我们发现大多数物种对的生态位之间存在低相关性（r < 0.4），这表明大多数物种具有不同的越冬策略。在雪上运动成本方面的形态学优势并不总是能扩大生态位宽度。相反，空间生态位可能会对以下情况做出反应：（1）由于积雪导致林下植被减少而引起的剧烈景观变化，这可能导致捕食者 - 猎物相互作用的改变；（2）冷空气团，这会影响体温调节成本和食物可获取性。当出现异常降雪时，体型较大的非树栖物种可能会发生生态位转移，而体型较小或半树栖的哺乳动物则不会。此外，与杂食动物相比，由于极端气候下食物可获取性降低，食草动物的生态位宽度更容易受到严重限制。
饮食习惯和体型可能决定生态位宽度的冗余度，这可能决定对极端降雪事件的稳健性/脆弱性。
