White-footed mouse (Peromyscus leucopus) response to restoration of grassland alvar.

Grassland alvar is a rare plant community that occurs throughout North America and northern Europe, and may require control of encroaching vegetation to be maintained or restored. We evaluated the hypothesis that restoration techniques used to restore the alvar ecosystem do not lead to declines in small mammal abundance. More specifically, we used a BACI design to compare how two methods of vegetation control, prescribed burns and mechanical removal, affected small mammal populations. The restoration was conducted beginning in 2019 on Pelee Island, Ontario, Canada. Live trapping of small mammals and associated vegetation sampling were conducted before and after on treatment and control locations. The only small mammal species to be caught during the study was the white-footed mouse (Peromyscus leucopus (Rafinesque, 1818)), which had an observed decrease across all treatment sites and the control site. Generalized linear mixed effects models demonstrated that the main effects of treatment and year best explained mouse abundance at the site level. Interannual variability appeared to explain more variation in mouse abundance than treatment effects. Our study did not provide strong evidence that the vegetation control measures we employed might limit white-footed mouse abundance.

草原阿尔瓦群落（Grassland alvar）是一种稀有植物群落，广泛分布于北美及北欧全境，其维持或恢复往往需要对侵入性植被实施管控。本研究针对“用于恢复阿尔瓦生态系统的修复技术不会导致小型哺乳动物种群丰度下降”这一假说开展评估。具体而言，本研究采用BACI设计，对比了两种植被管控手段——计划火烧（prescribed burns）与机械清除法（mechanical removal）——对小型哺乳动物种群的影响。该修复实验于2019年在加拿大安大略省皮利岛（Pelee Island）启动。研究人员在处理组与对照组样地的干预前后，均开展了小型哺乳动物活体诱捕及配套植被采样工作。本研究仅捕获到一种小型哺乳动物：白足鼠（Peromyscus leucopus (Rafinesque, 1818)），其种群丰度在所有处理组样地与对照组样地中均出现观测性下降。广义线性混合效应模型（Generalized linear mixed effects models）结果显示，处理方式与年份的主效应能够最佳解释样地水平的白足鼠种群丰度。相较于处理方式的影响，年际波动对白足鼠种群丰度变异的解释度更高。本研究未发现充足证据表明，本研究采用的植被管控措施会限制白足鼠的种群丰度。