Where are all these coyotes coming from?

 

 

Bonnie, still sporting her old collar, a few days before her recapture.

Bonnie, still sporting her old collar, a few days before her recapture. Photo by Dr. Numi Mitchell.

Note: This is part one of a two-part story.

In 1996, the bay froze and the coyotes came. No one knows exactly why. The winter was harsh, like the one just past. Food was tough to come by, and perhaps the signs were promising that on Aquidneck Island, or maybe Conanicut Island, life would be easier. Anyway, they came. And that was when the trouble began.

Sometime later, a woman was walking her dog off leash in a local park. It was a small animal, well within the range of what a coyote would regard as food. Several of them attacked the dog, killing it. The woman, understandably upset by the terrifying experience, wanted an expert to study the villains. The call went out: would someone please be kind enough to tell me how to wipe these animals off the planet?

Lucky for the coyotes, the call was answered by Dr. Numi Mitchell, Lead Scientist and Project Director of the Narragansett Bay Coyote Study.

Trapped

It’s April and it’s cold and it’s coyote time. Dr. Mitchell has gotten a call from one of her volunteers that there’s a coyote in a trap she has set on Aquidneck Island. The trap is baited with woodchuck, what Mitchell calls “coyote crack” for its effectiveness in drawing in coyotes, and this morning proves she wasn’t exaggerating. Across the field of a small farm, where the muddy fields end and the dense brush begins, is a small brown figure. Covered in mud, she presents a pathetic figure, though her health will turn out to be quite good.

Dr. Mitchell places a net over the coyote.

Dr. Mitchell places a net over the coyote.

“This is Bonnie, from a pair I called Bonnie and Clyde,” Mitchell says. “I named them that because they were just so good at getting deer! Clyde passed away, but I’m really excited to see Bonnie again.”

The team approaches the coyote quietly, slowly, to minimize her alarm. Mitchell carries a large net, its four-foot diameter held open by a circular aluminum tube. She quickly places the net over the coyote, gathering up any slack in order to restrict the animal’s movement. Ralph Pratt, Chief Veterinarian for the Coyote Project Study, immediately moves to the coyote and injects her with a tranquilizer. Once done, team members place blankets over her to keep her warm and calm while the drug takes effect. We must be quiet during this time, “Otherwise we’re in big trouble,” Mitchell says.

Dr. Ralph Pratt, DVM, preps the tranquilizer while Numi looks on.

Dr. Ralph Pratt, DVM, preps the tranquilizer while Numi looks on.

There Goes the Neighborhood

Coyotes are native to America, says Mitchell. Long ago, they worked their way from their earliest territories in the West across Canada to the East. Along the way, coyotes mated with wolves, and today most coyotes have at least some wolf in them. The migration coincided with the eradication of the wolf as more of America became settled and people both feared and hated the Alpha predators. Coyotes were smaller, and better able to avoid the efforts of farmers and other human foes to wipe them out. When the wolves were driven out, the coyotes moved in.

In more recent times, two problems have combined to make a coyote’s life more complicated: a deer population explosion and the expansion of human development. The deer, which have caused huge problems in terms of habitat destruction and incidents of Lyme disease from the ticks they carry, attract coyotes.

Coyotes, like many animals, are capable of increasing or decreasing their litter size based on the availability of food. Thus, while the average number of pups in a normal year may be two to five, coyotes may have as many as 13 when the living is easy. In areas like Aquidneck Island, deer are plentiful, which increases the size of coyote litters. That gave Dr. Mitchell a starting point.
“What do coyotes eat? Absolutely everything,” she says. “Fruit, deer, pet food, rodents, you name it.” Mitchell began to observe several packs of coyotes using radio collars which transmitted signals revealing their locations several times a day. They usually live in packs, though some are solitary, and spend all their time out in the open save for when females are about to pup, during which time they will use a den. Given the coyote’s intrinsic ability to control their litter size based on food availability, Mitchell wondered whether regulating their food might be the best way to control the population. The radio collars would help her answer that question.

Bonnie is kept warm and quiet while the tranquilizer takes effect.

Bonnie is kept warm and quiet while the tranquilizer takes effect.

“Family groups are extremely territorial. They claim a given area and will defend the boundaries faithfully.” Between each of the half dozen or so territories Mitchell began studying were corridors, a kind of no-man’s-land where adolescents and loners not affiliated with a given family could move from one part of the island to another and not be driven off by a pack. This pattern of behavior was discovered through the use of Mitchell’s radio collars. What she began to realize, however, is that controlling the coyote population would be much more difficult than controlling the deer population. There was an animal whose behavior had a far greater influence on coyotes than deer, woodchuck, or fruit trees: human beings.

Next time: mounting evidence suggests that coyotes are on the rise due to human intervention. Find out when the second half drops by following me on FB here.

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