Ganoe Laken S, Mayer Amy E, Brown Charles, Gerber Brian D
Department of Natural Resources Science University of Rhode Island Kingston Rhode Island USA.
Fish and Wildlife Division Rhode Island Department of Environmental Management West Kingston Rhode Island USA.
Ecol Evol. 2024 Jul 21;14(7):e70043. doi: 10.1002/ece3.70043. eCollection 2024 Jul.
Understanding mesocarnivore responses to both natural and anthropogenic disturbance is crucial for understanding species' potential to maintain landscape persistence into the future. We examined the response of five mesocarnivore species (bobcat, coyote, fisher, gray fox, and red fox) to both types of disturbances and climatic conditions. The Northeastern U.S. has experienced multiple large-scale disturbances, such as a mass defoliation event following larval spongy moth outbreak and high densities of infrastructure that divide the natural landcover into roadless zones where these species inhabit. Using dynamic occupancy models in a Bayesian framework, we aimed to (1) examine variation in species' responses over a 4-year study by estimating variation in site-level occupancy, colonization and extirpation of each species in the state of Rhode Island relative to natural disturbance (i.e., defoliation event), anthropogenic disturbance (i.e., parceling of natural landcover bounded by roads, distance to roads), and climate (i.e., seasonal precipitation) and (2) compare current occurrence trends to predicted asymptotic occupancy to identify key variables contributing to distribution instability. Our findings indicated declines in the occurrence of both fox species, and fisher. There was variation in mesocarnivore response to disturbance among the species. We found gray fox and fisher occupancy dynamics to be sensitive to all forms of disturbance and coyote occurrence was positively associated with anthropogenic disturbance. Although bobcat and red fox were predicted to respond positively to future climate scenarios, fisher and gray fox were not, and persistence of fisher and gray fox in a landscape of disturbance relies on large areas with high forest and shrubland cover. With the wide-spread spongy moth outbreak across much of southern New England, our findings indicate that efforts to conserve forested lands may be crucial in maintaining the persistence of several mesocarnivore species in this region experiencing large-scale disturbance.
了解中型食肉动物对自然和人为干扰的反应对于理解物种在未来维持景观持续性的潜力至关重要。我们研究了五种中型食肉动物（短尾猫、郊狼、渔貂、灰狐和赤狐）对这两种干扰类型和气候条件的反应。美国东北部经历了多次大规模干扰，例如舞毒蛾幼虫爆发后的大规模落叶事件以及高密度的基础设施，这些基础设施将自然土地覆盖分割成这些物种栖息的无路区域。在贝叶斯框架下使用动态占用模型，我们旨在：（1）通过估计罗德岛州每个物种在场地水平的占用、定殖和灭绝相对于自然干扰（即落叶事件）、人为干扰（即由道路界定的自然土地覆盖的分割、与道路的距离）和气候（即季节性降水）的变化，来研究物种在为期4年的研究中的反应变化；（2）将当前的出现趋势与预测的渐近占用进行比较，以确定导致分布不稳定的关键变量。我们的研究结果表明，两种狐狸物种以及渔貂的出现率都有所下降。不同物种的中型食肉动物对干扰的反应存在差异。我们发现灰狐和渔貂的占用动态对所有形式的干扰都很敏感，而郊狼的出现与人为干扰呈正相关。尽管预计短尾猫和赤狐对未来气候情景会有积极反应，但渔貂和灰狐则不然，渔貂和灰狐在干扰景观中的持续性依赖于大面积的高森林和灌木覆盖区域。随着新英格兰南部大部分地区舞毒蛾的广泛爆发，我们的研究结果表明，保护林地的努力对于维持该地区经历大规模干扰的几种中型食肉动物物种的持续性可能至关重要。
