Humans drive spatial variation in mortality risk for a threatened wolf population in a Canis hybrid zone

Large carnivores often exhibit high survival rates in protected areas,
whereas intentional and unintentional human-caused mortality may be
greater in adjacent areas. These patterns can result in source-sink
dynamics and limit population expansion beyond protected areas. We used
telemetry data from 438 canids in 141 packs collected from 2002–2020 to
evaluate mortality risk for wolves, coyotes, and admixed canids in a
3-species hybrid zone in and adjacent to a large protected area in
Ontario, Canada. The hybrid zone is occupied by most of the remaining
eastern wolves (Canis lycaon), a rare, threatened species that hybridizes
with sympatric eastern coyotes (C. latrans) and Great Lakes gray wolves
(C. lupus). Within Algonquin Provincial Park (APP), annual human-caused
mortality from harvest and vehicles was low (0.06, 95% CI [0.03, 0.08]),
whereas annual human-caused mortality was higher in adjacent areas (0.31,
95% CI [0.25, 0.37]). Smaller protected areas implemented to help protect
eastern wolves did not significantly reduce mortality. Eastern wolves
survived poorly relative to other canids and dispersing canids survived
poorly relative to residents. Mortality risk was greater when canids were
closer to roads. Mortality risk was also increased or reduced by the
strength of individual-level selection or avoidance of roads relative to
their availability, respectively. Our results provide a comprehensive
evaluation of factors influencing spatial variation in mortality risk for
canids to inform eastern wolf recovery efforts. Additionally, we developed
a novel modeling approach for investigating the influence of resource
selection on mortality risk, which highlighted that individual-level
responses to risk can strongly influence population-level mortality
patterns. Synthesis and applications. Despite being listed as ‘threatened’
under the Ontario Endangered Species Act, eastern wolves are still legally
trapped and shot outside protected areas in central Ontario. Eastern
wolves and dispersing canids survive poorly outside of APP, primarily from
human-caused mortality. These results, along with the apparent inadequacy
of the smaller protected areas, suggest that expanding the threatened
eastern wolf population outside APP is unlikely under current management
conditions. Protecting eastern wolves from human-caused mortality is
complicated as it would require a harvest ban for all canids, including
coyotes.