Compared with the ancestral coyotes from the plains, the northeastern coyote–wolf hybrids have larger skulls, with more substantial anchoring points for their jaw muscles. Thanks in part to those changes, these beefy coyotes can take down larger prey; they even killed a 19-year-old female hiker in Nova Scotia in 2009. The northeastern coyotes have expanded their range five times faster than coyote populations in the southeastern United States, the members of which encountered no wolves as they journeyed east.
New to the city
Coyotes have even moved into Washington DC, appearing in Rock Creek Park in 2004, just a few miles from the White House. Christine Bozarth, a conservation geneticist at the Smithsonian Institution in Washington, has tracked their arrival and has shown that some of them are descended from the larger northeastern strain and carry wolf DNA. Bozarth says the coyotes are there to stay. “They can adapt to any urban landscape; they'll raise their pups in drainage ditches and old pipes,” she says. She hopes that the coyotes will help to control the deer, whose numbers are booming. But Kays says that coyotes have not made a significant dent in the northeast's deer population. “Coyotes fill part of the empty niche, but they don't completely replace wolves,” he says.
Oddly enough, it is the smaller coyotes in the southeastern United States that seem to be having a real impact on deer. About the same size as western coyotes, the southeastern ones have begun to exploit a niche left empty by the red wolves (Canis lupus rufus) that once roamed the southeast and specialized in hunting the region's deer, which are smaller than those in the northeast.
John Kilgo, a wildlife biologist with the US Forest Service in New Ellenton, South Carolina, and his colleagues found in a 2010 study that South Carolina's deer population started to decline when coyotes arrived in the late 1980s. More recently, he and his colleagues have studied deaths among fawns, using forensic techniques right out of a murder investigation. They analyzed bite wounds on the carcasses and sequenced DNA in saliva left on the wounds. They also searched for scat and tracks left by the killers and noted how they had stashed uneaten remains. More than one-third of the fawn deaths were clearly caused by coyotes, and circumstantial evidence suggests that the true number might be closer to 80%. “Coyotes are acting as top predators on deer, and controlling their numbers,” says Kilgo.
At first, many researchers had a hard time accepting that conclusion because they thought that coyotes were too small to affect deer populations, Kilgo says. He hopes to study how the newly arrived coyotes will affect other members of the southeastern ecosystem, including wild turkeys and predators such as raccoons, foxes and opossums.
There is no danger that the southeastern coyotes will drive the abundant deer in that region to extinction. But at the northern extreme of their range, coyotes are threatening a highly endangered band of woodland caribou (Rangifer tarandus caribou) in the mature forests of Quebec's Gaspésie National Park. Logging and other changes there had taken a toll on the caribou even before coyotes arrived in the region in 1973 and settled into newly cleared parts of the forest. But then coyotes started hunting caribou calves and the population dropped even further.
A 2010 study found that coyotes accounted for 60% of the predation on these caribou, which now number only 140. Dominic Boisjoly, a wildlife biologist with Quebec's Ministry of Sustainable Development, Environment and Parks in Quebec City, says that the best way to protect the caribou would be to cease clear-cutting of the forest, thereby denying the predators a home.
Coyotes have been taking advantage of the changes wrought by humans for many thousands of years, according to a study of coyote fossils published this year. Evolutionary biologist Julie Meachen at the National Evolutionary Synthesis Center in Durham, North Carolina, and Joshua Samuels at the John Day Fossil Beds National Monument in Kimberly, Oregon, made that discovery by measuring the size of coyote fossils dating back over the past 25,000 years. During the last ice age, coyotes were significantly larger than most of their modern counterparts and resembled the biggest of the present-day coyote–wolf hybrids in the northeast. They probably scavenged meat from kills made by dire wolves and saber-toothed cats, and preyed on the young of the large herbivores, such as giant ground sloths, wild camels and horses, that thronged North America at that time.
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8 Comments
Add CommentIt seems almost politically incorrect to read about a successful wild animal.
Reply | Report Abuse | Link to thisI believe there is a First Nations story that when the last man on Earth finally dies there will be a coyote, just out of reach, watching him and laughing.
Reply | Report Abuse | Link to thisI wait the news that NRA farmers have risen to thwart this nature-created solution to deer populations explosions (caused by NRA- & farmer-supported near-extinction of natural predators) by declaring evolving coyotes to be threats that they then hunt to near extinction.
Reply | Report Abuse | Link to thisThere have been bounties and traps for coyotes here in the Northwest for many years, Coyote hunting is a popular "sport" with very high powered, accurate, and "flat" trajectory rounds. Coyotes are fast, small, and smart. They are evidently evolving faster than the hunters as there are still a lot of them left. There used to be a market for coyote fur but with the anti-fur movements this has mostly dried up. These people were the most effective coyote preditors
Reply | Report Abuse | Link to thisI hope the researchers are correct about the coyote controlling deer herds. I have my doubts. Having managed a 300 acre farm in south central WIsconsin for nearly 50 years, I do not believe the arrival of coyotes had any effect on the deer population at all. Our property has been perpetually at 50-100 deer per square mile even though coyotes showed up in force 20 years ago.
Reply | Report Abuse | Link to thisThe only force that has had any effect has been has been human predation. Over the past 5 years using state sanctioned hunting, we have been able to reduce the herd to 10-15 deer. This is still to many but with the reduction in browsing, the native plant species have rebounded to an amazing degree.
Hopefully the coyotes and wolves can keep these numbers at the current levels but as far as bringing down excessive population densities, I have my doubts.
SSM why not try farming deer as we do here in New Zealand. The venison market can be very lucritave.
Reply | Report Abuse | Link to thisUrban animals are probably all starting to diverge from their rural counterparts. In urban areas, their main "predator" is a vehicle and it doesn't behave properly. Urban animals should be starting to display adaptive responses. In some animals this might be showing up as truncation, and replacement of one set of behaviours for another. In others their should be the beginnings of increases in neural networks to hold their old survival and new survival behaviours.
Reply | Report Abuse | Link to thisThere were coyotes in Arlington in the early 90's. If they weren't seen in Rock Creek Park until 2004, it's because nobody was paying attention. I used to see them in our neighborhood off Military Rd, and there was a female with pups around Marymount I observed over several years.
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