MacNearney Doug, Pigeon Karine, Stenhouse Gordon, Nijland Wiebe, Coops Nicholas C, Finnegan Laura
fRI Research Caribou Program Hinton Alberta Canada.
fRI Research Caribou Program Hinton Alberta Canada; fRI Research Grizzly Bear Program Hinton Alberta Canada.
Ecol Evol. 2016 Aug 18;6(18):6484-6509. doi: 10.1002/ece3.2362. eCollection 2016 Sep.
Anthropogenic landscape change (i.e., disturbance) is recognized as an important factor in the decline and extirpation of wildlife populations. Understanding and monitoring the relationship between wildlife distribution and disturbance is necessary for effective conservation planning. Many studies consider disturbance as a covariate explaining wildlife behavior. However, we propose that there are several advantages to considering the spatial relationship between disturbance and wildlife directly using utilization distributions (UDs), including objective assessment of the spatially explicit overlap between wildlife and disturbance, and the ability to track trends in this relationship over time. Here, we examined how central mountain woodland caribou () distribution changed over time in relation to (i) anthropogenic disturbance, baseline range (defined using telemetry data from 1998 to 2005), and alpine habitat; and (ii) interannual climate variation (North Pacific Index; NPI). We developed seasonal UDs for caribou in west-central Alberta and east-central British Columbia, Canada, monitored with GPS collars between 1998 and 2013. We mapped the cumulative annual density of disturbance features within caribou range and used indices of overlap to determine the spatial relationship and trend between caribou UDs, anthropogenic disturbance, baseline range, alpine habitat, and the NPI. Anthropogenic disturbance increased over time, but the overlap between caribou UDs and disturbance did not. Caribou use of alpine habitat during spring, fall, and late winter increased over time, concurrent with a decrease in use of baseline range. Overlap between caribou UDs and disturbance increased during spring and fall following relatively cold, snowy winters (high NPI), but overall, climate did not explain changes in caribou distribution over time. We provide evidence supporting the hypothesis that caribou populations adjust their spatial distribution in relation to anthropogenic landscape change. Our findings could have implications for population persistence if distributional shifts result in greater use of alpine habitat during winter. Monitoring long-term changes in the distribution of populations is a valuable component of conservation planning for species at risk in disturbed landscapes.
人为景观变化（即干扰）被认为是野生动物种群数量下降和灭绝的一个重要因素。了解和监测野生动物分布与干扰之间的关系对于有效的保护规划至关重要。许多研究将干扰视为解释野生动物行为的一个协变量。然而，我们认为直接使用利用分布（UDs）来考虑干扰与野生动物之间的空间关系有几个优点，包括客观评估野生动物与干扰在空间上的明确重叠，以及跟踪这种关系随时间变化趋势的能力。在这里，我们研究了中部山区林地驯鹿（）的分布随时间如何变化，这与（i）人为干扰、基线范围（使用1998年至2005年的遥测数据定义）和高山栖息地有关；以及（ii）年际气候变化（北太平洋指数；NPI）。我们为加拿大艾伯塔省中西部和不列颠哥伦比亚省中东部的驯鹿制定了季节性UDs，这些驯鹿在1998年至2013年期间通过GPS项圈进行监测。我们绘制了驯鹿活动范围内干扰特征的年度累积密度图，并使用重叠指数来确定驯鹿UDs、人为干扰、基线范围、高山栖息地和NPI之间的空间关系和趋势。随着时间的推移，人为干扰增加了，但驯鹿UDs与干扰之间的重叠并没有增加。驯鹿在春季、秋季和冬末对高山栖息地的利用随着时间的推移而增加，同时对基线范围的利用减少。在相对寒冷、多雪的冬季（高NPI）之后的春季和秋季，驯鹿UDs与干扰之间的重叠增加，但总体而言，气候并不能解释驯鹿分布随时间的变化。我们提供了证据支持这样的假设，即驯鹿种群会根据人为景观变化调整其空间分布。如果分布变化导致冬季更多地利用高山栖息地，我们的研究结果可能会对种群的持续生存产生影响。监测种群分布的长期变化是受干扰景观中濒危物种保护规划的一个重要组成部分。
