Human land-use effects on mammalian mesopredator occupancy of a northeastern Connecticut landscape

Abstract

Mammalian mesopredators-mid-sized carnivores-are ecologically, economically, and socially important. With their adaptability to a variety of habitats and diets, loss of apex predators, and forest regrowth, many of these species are increasing in number throughout the northeastern United States. However, currently the region is seeing extensive landscape alterations, with an increase in residential and industrial development, especially at the expense of existing forest and small-scale farmland. We sought to understand how important an existing mosaic of working lands (timberland and farmland) in a forested landscape is to mesopredator species. We did this by studying mesopredator occupancy across three land uses (or habitat types): forest reserve (protected), timber harvest (shelterwood cuts), and field (both crop yielding and fallow) in and around a 3200-ha forest in northeastern Connecticut. We examined coyote (Canis latrans), bobcat (Lynx rufus), fisher (Pekania pennanti), and raccoon (Procyon lotor) occupancy using paired camera traps across juxtaposed reserve, shelterwood, and field units from April 2018 to March 2019. We created a priori habitat variable models for each species and season, as well as analyzed the impact of habitat types on each species. Throughout the year bobcats were positively associated with foliage height diversity and had the highest use in shelterwoods and lowest use in fields. Land use utilization varied seasonally for coyotes and raccoons, with higher use of fields than reserves and shelterwoods for half the year and no difference between land uses and the other half. Both species were not strongly associated with any particular habitat variables. Reserve forest was moderate to highly used by all species for at least half the year, and highly use year-round by fishers. Our findings reveal that a mosaic of intact forest and working lands, timber harvest, and agriculture can support mesopredator diversity.

Keywords: camera trapping; carnivore conservation; forest management; land use; timber harvesting.

FIGURE 1

The camera trap sites in and around Yale Myers Forest, northeastern Connecticut. Twenty‐four sites were in shelterwoods, twenty‐four were in reserve forest, and twelve were in fields

FIGURE 2

Model averaged occupancy estimates, interpreted as the probability of species use of an area, across seasons for (a) coyote, (b) bobcat, (c) raccoon, and (d) fisher mesopredators in three different habitat types in a managed and developed mixed‐hardwood forest landscape in northeastern Connecticut. Mesopredator species occupancy estimates represent probability (0–100%). Values are mean ± one standard error