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Tracking the coyote: headlines tell us these wild canids are in "our" territory more and more--a ROM mammalogist explains why.

They came across the snow-covered field one cold February morning just as I was finishing breakfast. I was excited when the first coyote caught my eye, and amazed to see two more following behind. Running with noses to the ground and tails down, they were obviously hunting, fanning out as they crossed our field into the property down the slope. I wondered what the shy, elusive coyote was doing hunting in broad daylight seemingly without a care near my property in Thornbury, Ontario.

People in this Beaver Valley community of southern Georgian Bay have been asking me questions about the local coyotes for some time now, and most of the questions have a common theme. Size. "Are you sure they're coyotes?" people ask. "They look too big to be coyotes."

According to ROM departmental associate Fiona Reid, author of A Field Guide to Mammals of North America (2006), coyotes run with their tails hanging down while wolves, which have shorter ears and larger feet, run with their tails up or straight out. It sounds simple. These animals definitely run with their tails down, which makes them coyotes. But the history of wolves and coyotes in Ontario is far from simple. It's a complex story of species interbreeding that biologists are still trying to unravel.

When European settlers first came to North America in the late 1500s to early 1600s, they found the coyote (Canis latrans) on the plains, grasslands, and deserts of the central and western parts of the continent. At that time the species appeared to prefer open and semi-forested habitat. Early in the 20th century, observers here in Ontario noticed that the coyote began a dramatic expansion of their territory that continues today.

In the early 1900s, there were no coyotes in central Ontario, let alone in southern Ontario or the Greater Toronto Area as there are today. According to an article published in 1937 in Rod and Gun by E. C. Cross of the ROM's mammal section, coyotes or brush wolves as they were then called were at that time restricted to northwestern Ontario. Cross used bounty and fur-trapping records to determine the changing distribution of coyotes in Ontario. By 1956 coyotes were found as far north as the shores of Hudson and James bays and south to the shores of Lakes Ontario and Erie. It had taken only 50 years to colonize the entire province of Ontario, and then another 25 years to reach the Gaspe Peninsula, northeastern New Brunswick, and finally Cape Breton Island in northeastern Nova Scotia, where in 2009 a young woman visiting from Toronto was fatally attacked by coyotes in Cape Breton Highlands National Park.

The reasons for the coyote's rapid expansion are complex and not fully understood, but certainly humans have contributed greatly to it. We have cleared forests and turned them into agricultural fields, and we have provided reliable food sources in the form of domestic livestock, garbage, and occasionally our pets. And, through habitat destruction and persecution, we have removed the one species that would naturally have kept the coyote in check, the grey wolf (Canis lupus).

Originally, the coyote's range was limited by the presence of this larger and more powerful canid in the north and east of North America. To the south of grey wolf territory, another species, the red wolf (Canis rufus), once lived. Very little is known about the natural history of this wolf because its range and numbers were already severely reduced when scientific investigations began in the mid 1800s. But its decline likely allowed the coyote to expand eastward in the southern United States. The later decline of the grey wolf and extirpation of the red wolf made way for the very adaptable coyote to expand its range into forests, agricultural areas, urban ravines, and the backyards of eastern North America.

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But to fully understand canid history, and therefore what is happening today, we need to look back even further in time, to the fossil record. When Europeans arrived in North America, the three large species of wild canids--the grey wolf, the red wolf, and the coyote--were already here. The largest and most widely distributed was the grey wolf, a species whose large size (averaging 36 kg), intelligence, and social nature made it well adapted as the major predator of northern ungulates, or hoofed mammals, such as moose, deer, elk, caribou, and sheep. Information from the fossil record indicates that the grey wolf, a species that evolved in the Old World, made its way into North America via the Bering Land Bridge, becoming well established in Alaska some 300,000 years ago. It did not appear south of the area covered by the Laurentide Ice Sheet (which reached its most recent and maximum extent about 18,000 years ago) until 10,000 to 12,000 years ago, when it is found in southern Alberta, southern Saskatchewan, and the bordering US states. Gradually, the grey wolf spread east across northern Canada following the retreating ice sheet, the last remnants of which disappeared from Labrador 5,000 years ago.

With such a widespread distribution comes a considerable amount of geographic variation, which caused the evolution of many different subspecies of the grey wolf. Originally thought to be among them was Canis lupus lycaon, the wolf that originally occupied the region from eastern Minnesota to the Atlantic and from central Ontario to parts of the northeastern United States. In recent years, some scientists have suggested that this subspecies is actually a distinct species, the eastern wolf (Canis lycaon), closely related to or even the same species as the red wolf (Canis rufus). Certainly the two look quite similar. In the past 300 years, due to habitat destruction and persecution, these eastern wolves have suffered a drastic loss in numbers and distribution and today are thought to exist only in central Ontario and the adjoining area of Quebec.

Unlike the grey wolf, the coyote and the red wolf originated in North America, likely shared a common evolutionary history, and were already well established by the time the grey wolf became one of the most widely distributed land mammals in North America (dating back 10,000 years). Common and widespread throughout the last 300,000 years, the coyote's range extended from Alaska to Pennsylvania and from Florida to Mexico. Looking through fossil records, it is clear that early coyotes were larger than today's but over time there was a gradual transition in size along with a reduction in the amount of territory they inhabited, down to that found by Europeans when they arrived in western North America in the 1500s (see top map). Today's coyote in Western North America, which eats a variety of foods, including small mammals, birds, berries, insects, and carrion, is the smallest of the canid species, weighing 7 to 14 kg.

The red wolf has a scant fossil history dating back to 10,000 years ago in Florida, Arkansas, Texas, and Mexico but is also known from a number of archaeological sites in the eastern United States. Based on these sites, we know that the red wolf was found in pine and broadleaf forests throughout the southeastern United States from eastern Texas and Oklahoma, to southern Indiana and New Jersey.

This wolf is larger (20 to 40 kg) and more robust than the coyote and somewhat smaller and more delicately built than the grey wolf. It lives on small to medium-sized mammals such as rabbits, hares, and birds, but can also take deer. A behavioural character that separates it from the coyote is its habit of running with its tail out or up, similar to the grey wolf. Presently the red wolf is endangered. It had vanished from the wild because of habitat loss, hunting, and trapping but captive populations have been maintained since the 1970s and some have been released into parts of the southeastern United States.

So, how does all this relate to the large coyotes that ran across my field near southern Georgian Bay? Why are these coyotes so large? Perhaps the coyote is a very adaptable species, and in its new environment, without competition from the larger grey wolf, it has evolved a larger body size, which would be advantageous for hunting larger prey.

But there is a less speculative way to answer the question-- genetics. There has been a lengthy debate over the origins of the two recognized wolf species inhabiting eastern North America-- the red wolf in the eastern United States (re-introduced through captive breeding programs) and the eastern wolf in Ontario's Algonquin Park and surrounding areas. A recent genetic study, led by Robert Wayne of the University of California, Los Angeles, concluded that eastern wolves in Algonquin Park are mostly grey wolf and a mixture of previously hybridized wolf/coyote and not a separate species.

Wayne's analysis, which assessed genetic diversity in dogs, wolves, and coyotes, found that two eastern wolf samples from Algonquin had 60 percent grey wolf ancestry and 40 percent coyote. They tested coyotes from New York, New Hampshire, Vermont, Connecticut, and Quebec and found them to be on average 84 percent coyote, 8 percent grey wolf, and 8 percent dog.

In a separate study, Roland Kays of the Buffalo Natural History Museum found evidence that coyotes near the Great Lakes in the United States migrated east and bred with grey wolves. These hybrid animals, still considered coyote, have become the top predator in the eastern US, filling the void left by the disappearing eastern wolf, which was hunted out of existence in the United States.

Some scientists, however, are skeptical of the notion that eastern wolves are hybrids of grey wolves and coyotes. In this camp is David Mech, a grey wolf expert who has studied these animals for more than 50 years. Typically, grey wolves do not mate with coyotes, but usually kill them, he says. In the west, where coyotes and grey wolves live in close proximity, there is no evidence of such hybridizing behaviour. Mech has observed that when the Minnesota population he studies dropped below one wolf per 39 square kilometres, coyotes from the immediately surrounding area invaded. John and Mary Theberge, studying the wolves in Algonquin Park from 1987 to 1998, found similar evidence of coyote encroachment when wolf populations within the park declined to a similar level.

Canadian researchers led by Paul Wilson from Trent University, studying the genetics of Ontario wolves, have agreed that indeed there is hybridizing happening within Ontario, but between the eastern wolf (Canis lycaon), including the ones in Algonquin Park and the Tweed-to-Magnetawan areas, and the coyote in central Ontario. According to their evidence, the eastern wolf is also moving west and mating with grey wolves in the area of Ontario north of the upper Great Lakes.

For me, the interpretation that makes most intuitive sense combines several lines of evidence. Since the studies summarized here examined different animals from various areas using different methods, it's not unexpected to see different interpretations and conclusions for each study. What is certain is that the eastern wolf was recognized as different from coyote and formally described as early as 1755, almost 200 years before the coyote invaded from the west. So the animal present in central Ontario and around the Great Lakes at that time was free of modern hybridizing coyote genes.

But, it was not necessarily free of older coyote genes. A group of scientists led by Brad White of Trent University has just reported on 400- to 500-year-old Canis samples excavated from a pre-contact Iroquois village in London, Ontario. Two of the samples show genetic sequences matching those of present-day coyote, not grey wolf. Comparing their tooth morphology, however, shows eastern wolf rather than coyote origin. This discovery suggests that the New World-evolved eastern wolf and not the grey wolf occupied this region prior to the arrival of Europeans, although eastern-grey wolf hybrids cannot be ruled out. This further supports the theory of a shared ancestry between eastern wolves and western coyotes. Hybridizing could have happened over the last 18,000 years during the last glaciation. White's group also suggests that the grey wolf did not inhabit the deciduous forests of eastern North America but was associated with the boreal forest and the Precambrian shield. The grey wolf and the eastern wolf would likely have hybridized more recently, once they came into contact after the retreat of the ice, in and around those areas where deciduous and boreal forest mix.

Whatever is happening, the wild canids of Ontario are something of an alphabet soup of coyotes, wolves, and dogs. While these species can interbreed, such behaviour is not typical; historically they have maintained a certain level of breeding integrity. Changes to Ontario's habitat have likely enabled some of the recent hybridization that has occurred. The changed environment may now favour the smaller deer-eating wolf Canis lycaon in areas that are still forested and has certainly allowed coyotes to expand into rural Ontario. This changing face of the canids in Ontario is not necessarily a negative development. The animals are adapting to changed environments.

And so, this brings us back to the question of why the coyotes in Thornbury are so large and what they were doing hunting in daylight. It seems that coyotes have become accustomed to living in populated areas, and a rural field on an overcast February morning did not pose a threat to them. I think these animals are primarily coyote with small amounts of grey wolf and possibly dog DNA. They look like coyotes, they behave like coyotes, and for the most part they are coyotes. As a naturalist, I like to categorize, put species into boxes, to be able to distinguish a coyote from a grey wolf. But as a scientist, I realize that what I'm seeing is evolution in progress--evolution accelerated by humankind's hand.

If you go out in the woods today ...

What to do when coyotes are near

The changes in coyote distribution over the past 100 years tell me that these animals are with us to stay. As a resident of the city, I celebrate their presence in the ravines and in neighbourhoods adjacent to coyote habitat. In the country, they have become part of the established Ontario fauna. But wherever they interact with humans, they can cause problems. Let's accept them, observe them, and enjoy their presence, but be sensible about how we manage ourselves, our property, our pets, and our livestock. A few small precautions can help us avoid close encounters.

* Eliminate sources of food from your property, including pet food, food for wild animals, even fallen fruit. Coyotes are omnivorous and, like any animals, will be attracted to an easy source of food. They are curious and do not fear humans.

* Keep pets indoors, particularly at night.

* Clean up after your dog. Coyotes are attracted to dog feces.

* Fence your property with a fence at least 2 metres in height.

* Neuter or spay your dog. Coyotes are attracted to and will mate with domestic dogs not spayed or neutered.

* Do you keep livestock? Use llamas or donkeys, which are aggressive toward predators, to guard them.

* When you encounter a coyote, remain calm and face the animal. Do not run--the coyote will instinctively give chase.

Make noise and make yourself look larger by waving your arms.

* When walking your pet in coyote country, keep it leashed.

For more information, see the Ontario Ministry of Natural Resources website at www.mnr.gov.on.ca.
Canid facts at a glance: Comparing the North American species

Comparative summary of distribution and characteristics of
grey wolf, coyote, and eastern/red wolf
Based on A Field Guide to Mammals of North America

Common Name & Size &
Species Distinguishing
 Features

COYOTE Shoulder height 50-60 cm;
Canis latrans weight 7-22 kg

 Long legs; large ears;
 long narrow muzzle;
 body colour variable,
 greyish in north,
 tawny in south

GREY WOLF Shoulder height 70-80 cm;
Canis lupus weight 25-70 kg

 Large and long-legged;
 big feet and small ears;
 muzzle long, not greatly tapered;
 greyish on back

EASTERN WOLF / RED WOLF Shoulder height 70 cm;
Canis lycaon / weight Red Wolf:
Canis rufus 20-40 kg Eastern Wolf:
 25-30 kg
 Long-legged, rangy; ears large;
 colour variable, blackish,
 or reddish brown; legs reddish;
 back grey-brown

Common Name & Range
Species Historic

COYOTE Western Canada,
Canis latrans western United States
 to southern Mexico

GREY WOLF Northern and western
Canis lupus North America to Mexico

EASTERN WOLF / RED WOLF Central Ontario,
Canis lycaon / southern Quebec and
Canis rufus Great Lakes area, south
 through eastern United States
 to eastern Texas and Florida

Common Name & Range
Species Present

COYOTE Most of North America
Canis latrans from Alaska south to
 western Panama; western
 to eastern North America
 south of the treeline

GREY WOLF Alaska, northern and
Canis lupus northeastern Canada,
 reintroduced to western
 Wyoming and Idaho
 (from Canadian populations)

EASTERN WOLF / RED WOLF Algonquin Park and surrounding
Canis lycaon / area, southwestern Quebec,
Canis rufus reintroduced into Tennesee,
 Louisiana, North Carolina,
 Florida, and New Jersey
 from captive populations

Common Name & Habitat
Species

COYOTE Grasslands, deserts,
Canis latrans woodlands, mountains,
 agricultural and urban areas

GREY WOLF Boreal forest and tundra;
Canis lupus restricted to areas of
 extensive wilderness

EASTERN WOLF / RED WOLF Heavily forested areas of
Canis lycaon / eastern temperate forest
Canis rufus

Common Name & Habits
Species

COYOTE Highly adaptable; most active
Canis latrans at dawn or dusk in east,
 nocturnal or diurnal in west;
 eats a variety of food

GREY WOLF Mainly crepuscular but may
Canis lupus be active by day; eats
 mostly large mammals;
 very social species

EASTERN WOLF / RED WOLF Similar to grey wolf
Canis lycaon /
Canis rufus
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Article Details
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Author:Eger, Judith
Publication:ROM Magazine
Geographic Code:100NA
Date:Mar 22, 2012
Words:2941
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