Matrix Solutions Incorporated, Edmonton, Alberta T6H 5H6, Canada.
Ecol Appl. 2011 Jun;21(4):1011-6. doi: 10.1890/10-0949.1.
Resource selection is grounded in the understanding that animals select resources based on fitness requirements. Despite uncertainty in how mechanisms relate to the landscape, resource selection studies often assume, but rarely demonstrate, a relationship between modeled variables and fitness mechanisms. Using Canada lynx (Lynx canadensis) and snowshoe hare (Lepus americanus) as a model system, we assess whether prey habitat is a viable surrogate for encounters between predators and prey. We simultaneously collected winter track data for lynx and hare in two study areas. We used information criteria to determine whether selection by lynx is best characterized by a hare resource selection probability function (RSPF) or by the amount of hare resource use. Results show that lynx selection is better explained by the amount of hare use (SIC = -21.9; Schwarz's Information Criterion) than by hare RSPF (SIC = -16.71), and that hare RSPF cannot be assumed to reveal the amount of resource use, a primary mechanism of predator selection. Our study reveals an obvious but important distinction between selection and use that is applicable to all resource selection studies. We recommend that resource selection studies be coupled with mechanistic data (e.g., metrics of diet, forage, fitness, or abundance) when investigating mechanisms of resource selection.
资源选择基于这样一种理解，即动物根据适应度需求选择资源。尽管机制与景观之间的关系存在不确定性，但资源选择研究通常假设（但很少证明）模型变量与适应度机制之间存在关系。我们使用加拿大猞猁（Lynx canadensis）和雪兔（Lepus americanus）作为模型系统，评估猎物栖息地是否可以作为捕食者和猎物相遇的可行替代物。我们同时在两个研究区域收集了猞猁和雪兔的冬季足迹数据。我们使用信息准则来确定猞猁的选择是否最好由雪兔资源选择概率函数（RSPF）或雪兔资源利用量来描述。结果表明，猞猁的选择更多地由雪兔的利用量（SIC = -21.9；施瓦茨信息准则）来解释，而不是由雪兔 RSPF（SIC = -16.71）来解释，而且雪兔 RSPF 不能假定可以揭示资源利用量，这是捕食者选择的主要机制。我们的研究揭示了选择和利用之间一个明显但重要的区别，这适用于所有资源选择研究。我们建议，在研究资源选择机制时，将资源选择研究与机制数据（例如，饮食、饲料、适应度或丰度的指标）相结合。
