Assessing Small Mammal Richness and Abundance Following Wildfires

Abstract

As with all disturbance, wildfire transforms the abiotic and biotic features of the landscape. The Altona Flat Rock is a globally rare sandstone pavement pine barrens ecosystem dominated by an overstory of Pinus banksiana (jack pine) and understory of ericaceous shrubs including Vaccinium augustifolium (blueberry). In summer 2018, a wildfire burned approximately 225 hectares of the jack pine barrens, a fire-dependent ecosystem. The small mammal community provides essential ecosystem services as seed predators, dispersers, and as prey for higher trophic levels. We aimed to determine the abundance and diversity of the small mammal community at two sites, specifically 1) the recent 2018 wildfire versus 2) a regenerated forest that burned in 1957. As part of an on-going mark-recapture study at the Flat Rock, small mammal live trapping was conducted over a six-week period in fall 2022. Each individual was uniquely marked with an ear tag and body metrics (length, weight) and gender were collected. Data from the 2022 field season was combined with previous years which showed that the small mammal abundance has declined over time and the reference (1957) site had higher community diversity including insectivores, while the recent burn (2018) had a higher overall abundance of the dominant generalist Peromyscus sp.. Results from this on-going study, can inform more effective management strategies in fire-dependent ecosystems by optimizing small mammal habitat and benefiting the ecosystem as a whole to better support the larger wildlife community and regenerating forest.