A thorough study by John F. Benson et al. in Central Ontario considerably explicates the ecology of wild canids in Eastern North America.The paper,Ungulate predation and ecological roles of wolves and coyotes in eastern North America,was recently published in the April 2017 issue of Ecological Applications.Understanding the ecological roles of species that influence ecosystem processes is a central goal of ecology and conservation biology,the authors say.This study sought to clarify the predatory ability and ecological roles of the different top canid predators of Eastern North America by investigating intrinsic and extrinsic influences on per capita kill rates of white-tailed deer (Odocoileus virginianus) and moose (Alces alces) by canids of varying Canis ancestry in and adjacent to Algonquin Provincial Park in Central Ontario.Erroneously concluding that Eastern coyotes have replaced the ecological roles once performed by wolves could detract from wolf restoration efforts and the conservation of naturally functioning ecosystems.Thus studies of predation patterns of Eastern wolves (Canis lycaon) and Eastern coyotes (Canis latrans var.) are needed to critically evaluate the ecological functions performed by wild canids in Eastern North America.*
In 2015,the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) recommended that Eastern wolves be recognised as a separate species rather than a subspecies of Grey wolf.Currently the majority of Eastern wolves inhabit areas in and adjacent to Algonquin Provincial Park.Besides Eastern wolves,in the study we are reviewing today,admixed Grey wolves are referred to as Great Lakes-boreal wolves.The study combines GPS telemetry,field investigations,DNA analysis and environmental data to quantify predation on deer and moose by canids of varying Canis* ancestry in and adjacent to Algonquin Provincial Park.*
Previous studies revealed that Eastern wolves were the dominant resident canids in APP (estimated 63%).There are smaller numbers of Eastern wolf x Great Lakes-boreal wolf hybrids and wolf (Great Lakes-boreal and Eastern wolf) x Eastern coyote hybrids (29%),with whom they sometimes form packs.Eastern coyotes (estimated 64%) and Eastern coyote x wolf (Great Lakes-boreal and Eastern wolf) hybrids (29%) were the dominant resident canids of adjacent Wildlife Management Unit 49,where wolves were much rarer.Both APP and WMU 49 were characterised by hardwood,conifer and mixed forests interspersed with wetlands,lakes and rocky meadows.The landscapes have elevations ranging from 180-580 meters in APP and 79-549 meters in WMU 49.*
The authors note that Eastern coyotes have ascended to the role of apex predator across much of Eastern North America since the extirpation of wolves (Canis spp.) and there has been considerable confusion regarding their ability to prey on ungulates and their ecological niche relative to wolves.Eastern wolves are thought to have been the historical top predator in eastern deciduous forests and have previously been characterised as deer specialists that are inefficient predators of moose because of their smaller size relative to grey wolves (Canis lupus).*
In any event,the basic findings of the study under consideration suggest the following:
1.Eastern coyote ancestry within packs negatively influenced per capita total ungulate (moose and white-tailed deer) and moose kill rates.
2.Furthermore,such packs consumed significantly less ungulate biomass and more anthropogenic (human-related) food than packs dominated by wolf ancestry.
3.Similar to Grey wolves in previous studies,Eastern wolves preyed on deer when they were available.However,in areas of scarcity,Eastern wolves killed moose at rates seen previously among Grey wolves at comparable moose densities across North America.
4.Most critically,Eastern coyotes are effective deer predators,but their dietary flexibility and low kill rates on moose suggest they have not replaced the ecological role of wolves in Eastern North America.If this were not understood,ecosystems that are in fact in need of restoration by the reintroduction of wolves could be overlooked.*
Large remote tracts of mature forest inhabited primarily by moose rather than deer are rare in the Northeastern US,which will make Eastern wolf establishment difficult in the presence of abundant coyote populations,the authors point out.Reintroducing Great Lakes-boreal wolves may be advantageous given that hybridisation between sympatric (inhabiting the same area) Great Lakes-boreal wolves and coyotes appears to be minimal in areas where they overlap.Great Lakes-boreal wolves are aggressive with and behaviourally dominant to coyotes,whereas Eastern wolves tend to treat coyotes similar to conspecifics in territorial interactions,at least at the home range level.Great Lakes-boreal wolves have successfully colonised areas in Minnesota,Wisconsin and Michigan that were characterised by younger forests,habitat fragmentation and abundant coyotes,suggesting they could also persist in the Northeastern US.