Grenier-Potvin Alexis, Clermont Jeanne, Gauthier Gilles, Berteaux Dominique
Chaire de recherche du Canada en biodiversité nordique and Centre d'Études Nordiques, Université du Québec à Rimouski, 300 Allée des Ursulines, Rimouski, Québec, G5L 3A1, Canada.
Département de biologie and Centre d'études nordiques, Université Laval, 2325 Rue de l'Université, Québec, Québec, G1V 0A6, Canada.
Mov Ecol. 2021 Mar 20;9(1):12. doi: 10.1186/s40462-021-00250-0.
Movements and habitat selection of predators shape ecological communities by determining the spatiotemporal distribution of predation risk. Although intraspecific interactions associated to territoriality and parental care are involved in predator habitat selection, few studies have addressed their effects simultaneously with those of prey and habitat distribution. Moreover, individuals require behavioural and temporal flexibility in their movement decisions to meet various motivations in a heterogeneous environment. To untangle the relative importance of ecological determinants of predator fine-scale habitat selection, we studied simultaneously several spatial, temporal, and behavioural predictors of habitat selection in territorial arctic foxes (Vulpes lagopus) living within a Greater snow goose (Anser caerulescens atlantica) colony during the reproductive season.
Using GPS locations collected at 4-min intervals and behavioural state classification (active and resting), we quantified how foxes modulate state-specific habitat selection in response to territory edges, den proximity, prey distribution, and habitats. We also assessed whether foxes varied their habitat selection in response to an important phenological transition marked by decreasing prey availability (goose egg hatching) and decreasing den dependency (emancipation of cubs).
Multiple factors simultaneously played a key role in driving habitat selection, and their relative strength differed with respect to the behavioural state and study period. Foxes avoided territory edges, and reproductive individuals selected den proximity before the phenological transition. Higher goose nest density was selected when foxes were active but avoided when resting, and was less selected after egg hatching. Selection for tundra habitats also varied through the summer, but effects were not consistent.
We conclude that constraints imposed by intraspecific interactions can play, relative to prey distribution and habitat characteristics, an important role in the habitat selection of a keystone predator. Our results highlight the benefits of considering behavioural state and seasonal phenology when assessing the flexibility of predator habitat selection. Our findings indicate that considering intraspecific interactions is essential to understand predator space use, and suggest that using predator habitat selection to advance community ecology requires an explicit assessment of the social context in which movements occur.
捕食者的活动和栖息地选择通过决定捕食风险的时空分布来塑造生态群落。尽管与领地行为和亲代抚育相关的种内相互作用参与了捕食者栖息地选择，但很少有研究同时探讨它们与猎物及栖息地分布的影响。此外，个体在移动决策中需要行为和时间上的灵活性，以满足异质环境中的各种动机。为了厘清捕食者精细尺度栖息地选择的生态决定因素的相对重要性，我们在繁殖季节对生活在大雪雁（Anser caerulescens atlantica）群落中的领地北极狐（Vulpes lagopus），同时研究了栖息地选择的几个空间、时间和行为预测因子。
利用每隔4分钟收集一次的GPS定位数据以及行为状态分类（活跃和休息），我们量化了狐狸如何根据领地边界、巢穴距离、猎物分布和栖息地来调节特定状态下的栖息地选择。我们还评估了狐狸是否会因猎物可利用性下降（鹅蛋孵化）和巢穴依赖减少（幼崽独立）这一重要物候转变而改变其栖息地选择。
多种因素在驱动栖息地选择中同时发挥关键作用，且它们的相对强度因行为状态和研究时期而异。狐狸避开领地边界，繁殖个体在物候转变前选择靠近巢穴。狐狸活跃时会选择较高的雪雁巢穴密度，但休息时则会避开，且孵化后选择较少。对苔原栖息地的选择在整个夏季也有所变化，但影响并不一致。
我们得出结论，相对于猎物分布和栖息地特征，种内相互作用所带来的限制在关键捕食者的栖息地选择中可发挥重要作用。我们的结果凸显了在评估捕食者栖息地选择灵活性时考虑行为状态和季节物候的益处。我们的研究结果表明，考虑种内相互作用对于理解捕食者的空间利用至关重要，并表明利用捕食者栖息地选择来推进群落生态学需要明确评估移动发生的社会背景。
