The proof is in the poop: First density estimates for a recovering
bobcat population in southeast Ohio using DNA from scat
Abstract
The recovery of mammalian species in the US Midwest through natural
recolonization constitutes a conservation success story, yet management
remains challenging due to many unknowns related to population dynamics
and abundance. Abundance is a critical parameter for management
decisions, and estimating the density and abundance of elusive species,
such as terrestrial carnivores, remains challenging despite recent
technological advances. In this study, we evaluated density and
abundance of a recovering carnivore species, the bobcat (Lynx rufus) in
two areas of Ohio using non-invasive DNA from scat. The target areas in
eastern and southern Ohio have been shown to have uneven dynamics and
recolonization success and we expected that this would be reflected in
differences in density and abundance. We collected 298 bobcat scats
between July 2018 and April 2019 on 150 km of repeated transects. Of
these, 102 scats were successfully genotyped, and 55 individuals were
identified (33 in eastern Ohio and 22 in southern Ohio). Using Spatially
Explicit Capture-Recapture models, we estimated 17.9 ± 4.3 and 11.3 ±
2.9 bobcats/100 km2 in eastern and southern Ohio study areas,
respectively. Our results support prior telemetry data which indicated
that bobcats in eastern Ohio had smaller home-ranges than bobcats in
southern Ohio, and thus could support a higher density of individuals.
The higher densities were similar to other eastern US populations and
are much higher than other Midwestern recovering populations. Our
results provide a snapshot of the population status and can be used to
determine sustainable management strategies for Ohio’s bobcat population