BILLINGS – On a fall day in the Little Snowy Mountains, the Pavarotti of coyotes yipped and yapped endlessly in the distance as if serenading an appreciative crowd, just like the Italian opera singer. What could possibly merit such vivid vocalization, and not just on one day, but several?
Such actions by Canis latrans have helped the species occupy the human imagination for thousands of years and infiltrate folklore, art and even cartoons. The coyote as trickster or troublemaker is common in stories. Wile E. Coyote of cartoon fame is tirelessly attempting to kill the Roadrunner with fantastically complicated contraptions.
To many, though, the coyote is no joking matter. In his book “Today I Baled the Hay to Feed the Sheep the Coyotes Eat,” Grass Range artist and sheep rancher Bill Stockton wrote of the gruesome injuries and deaths coyotes inflicted on his sheep. But he also grudgingly praised one of his hated adversaries for its intelligence – it lived on his property but never killed sheep there to protect its family’s den site.
In spite of concentrated efforts to rid many regions of the West of the animals by shooting, trapping and poisoning, coyotes have been able to find safe havens in the human-altered rural and urban habitats and survive. It’s a trait that scientists call plasticity – the ability to adapt to a variety of habitats and foods.
Two recently published studies have given further insight into the animal’s adaptability today, and its ancestor’s inability to survive climate change thousands of years ago.
More than 10,000 years ago, coyotes were much larger, stronger and sturdily built than their modern descendants, according to fossil evidence.
During the Pleistocene era, between 1.6 million and 10,000 years ago, the coyotes of the time (C. latrans orcutti) had thicker and deeper skulls, a shorter, broader snout and wider teeth for eating meat.
In general, the Pleistocene was a time of much larger animals all across North America. On the plains that would have somewhat resembled today’s African savannah, there roamed huge predators like dire wolves and saber-toothed cats, which needed to be big to bring down equally large prey like giant sloths, mammoths and mastodons.
Researchers Julie Meachen and Joshua Samuels wondered why modern coyotes had shrunken so much in comparison to their ancestors. One possible theory was that they responded to a warming climate. The Bergmann’s rule of biology states that animals tend to grow larger in colder climates as a way to stay warm. If that were true, then coyotes that live farther north should be larger than their counterparts in lower latitudes. But that’s not the case.
The other possibility that the researchers considered – and the one that they found more plausible – was that coyotes adapted their size in response to a loss of large predator and prey species. Although there’s no direct evidence, it’s also possible that the arrival of humans at the end of the Pleistocene era may have contributed to the extinction of C. latrans orcutti.
“We suggest that Pleistocene coyotes may have been larger and more robust in response to larger competitors and a larger-bodied prey base,” the researchers concluded.
Oddly, gray wolves, which were also present in the Pleistocene, have changed little over the past 10,000 thousand years except for the loss of larger and stronger leg muscles.
After wolves were exterminated by Euro-Americans from much of the United States in the early 1900s, coyotes that were previously confined to the western U.S. by their competitors slowly expanded east of the Mississippi River. Now, coyotes have infiltrated New York City, the most populous urban area in the United States.
A coyote’s relatively small size – about 25 to 35 pounds and 16 to 20 inches tall at the shoulder – help it to hide from humans as it spreads into new territory. The coyote’s ability to live on a variety of small mammals – such as rodents, ducks and geese – that may thrive in urban areas also aided its expansion.
So is an urban coyote a good thing or a bad thing? Well, the canids’ arrival in cities and suburbs could mean a reduction in some species that have grown exponentially without predators – such as raccoons, white-tailed deer and Canada geese. Fewer of these animals could revive habitats deer have overgrazed, remove raccoons that raid garbage cans and thin out geese that pollute parks and golf courses with feces. Fewer mice and deer could mean a reduced incidence of Lyme disease, which is transmitted by deer ticks, researchers theorized.
On the flip side are concerns about coyotes becoming so comfortable around humans that attacks by coyotes on humans could escalate. Coyotes may also prey on pets, such as house cats and dogs.
“Ultimately what is needed is a balance of respect for the natural world and sensible caution towards the inherent wildness of undomesticated animals,” wrote Anne Toomey, a researcher at Wildmetro in New York City, in the spring issue of The Wildlife Professional.
Who knows, maybe someday a coyote will serenade a crowd outside New York’s Metropolitan Opera.