Lynx cycles and barriers: Evaluating dispersal versus climate change in flatlining populations

由专业捕食者及其猎物产生的持续和定期的种群周期在自然界中是罕见的，但似乎是在北方生态系统中创造周期性节奏的主要力量。加拿大山猫和雪鞋兔(Lepus Americanus)表现出这种普遍的10年周期。这些动态系统的健康处于危险之中，美国山猫的地位受到威胁，加拿大山猫南部地区的山猫数量很少，这就是明证。例如，近年来，加拿大南部和华盛顿州北部喀斯喀兹山脉的山猫数量大约减少了一半。山猫在加拿大-美国边境附近的持久性可能取决于与加拿大核心种群的扩散联系的质量，或者在气候变化永久改变物种动态之前阻止气候变化的进展。我们建议评估其他假设，以解释山猫-野兔周期周期和幅度的崩溃：捕食者扩散的同质化效应与环境季节性的减少，假设维持10年一次的周期。我的研究成果是：1)评估气候变化或扩散障碍是否是导致南部山猫循环破裂的主要生物学机制；2)使用放射性胶衣山猫样本创建一个栖息地模型，促进扩散，并制作栖息地/扩散图，识别通过物种范围南部关键山猫栖息地的移动障碍。了解扩散趋势对于管理栖息地碎片化和保护栖息地连接至关重要。或者，气候变化可能正在迅速破坏北方森林中的种群周期。此外，这项研究将使野生动物管理者、林业和其他资源采掘业、诱捕行业以及种群生态学的集体知识受益。

Persistent and regular population cycles produced by specialist predators and their prey are a rarity in nature, but appear to be a major force creating a periodic rhythm in boreal ecosystems. Canadian lynx (Lynx canadensis) and snowshoe hare (Lepus americanus) display such a pervasive 10-year cycle. The health of these dynamic systems are at risk as evidenced by the threatened status of the lynx in the US and low numbers in what remains of its southern range in Canada. For instance, lynx numbers in the Cascades Mountain Range of southern Canada and northern Washington have approximately halved in recent years. The persistence of lynx near the Canada-US border may depend on either quality of dispersal connections with the core Canadian population or stemming the progression of climate change before it permanently alters the species' dynamics.We propose to evaluate alternative hypotheses to explain the breakdown in the periodicity and amplitude of the lynx-hare cycle: the homogenizing effect of predator dispersal versus the reduction in environmental seasonality that is hypothesized to maintain the 10-year cycle. My research outcomes are to 1) evaluate if either climate change or barriers to dispersal is the main biological mechanism behind the breakdown of southern lynx cycles and 2) use a sample of radiocollared lynx to create a model of habitats that facilitate dispersal and produce habitat/dispersal maps identifying barriers to movement through key lynx habitats in the southern portions of the species' range.  Understanding dispersal trends is essential for managing habitat fragmentation and protecting habitat connections.   Alternatively, climate change might be rapidly dismantling population cycles in the boreal forest.  This study will benefit wildlife managers, forestry and other resource extraction industries, the trapping industry, and the collective knowledge of population ecology.