Nature Center Taking a Closer Look at Island Coyotes

The organization is working with the University of Washington to isolate DNA samples taken from scat

Coyotes are adaptable, highly intelligent and resourceful predators with heightened senses. They were once uncommon on Vashon, but their numbers have steadily risen over time, as evidenced by their late-night choir of yips and howls often heard by sleepy islanders.

Creeping past trail cameras under the cover of darkness in remote areas of Vashon, they briefly emerge through the trees or tall grass, their eyes glowing, before vanishing again.

Sightings are up all across Puget Sound, alarming islanders who own chickens and small pets, and have taken to social media to report their own sightings of the animals, spotted even during the daytime hours crossing the street or wandering around backyards.

Although coyotes prefer remote places away from humans, they are increasingly living in urban areas as their territory expands. On the Carnivore Spotter website, a collaborative effort by the Woodland Park Zoo and Seattle University to catalog citizen carnivore sightings, residents have reported numerous coyote sightings in communities all over Seattle in the last month.

The Vashon Nature Center has been working with the Prugh Lab at the University of Washington to isolate DNA samples from coyotes’ scat, which is the first research of its kind west of the Cascades. The study’s preliminary findings will be available soon, but according to Nature Center Director Bianca Perla, it will eventually reveal more information about the island’s coyote population and growth, as well as where they came from, and their biological characteristics compared to others in the region.

“We’re looking at how related our coyotes are to get an idea of how much immigration is happening, how much new blood is coming in,” Perla said.

Coyotes have been tracked on Vashon for a long time. The Beachcomber published the first known record of a coyote on Vashon in 1960 after a resident shot and killed one. Equestrian riders in Paradise Ridge could hear the animals in the woods by the 1990s. In the mid-2000s, the Nature Center captured a photo of a coyote on Vashon.

Enterprising coyotes probably found their way to the island by swimming across Colvos Passage, Perla said, noting that at low tide the channel is less than a mile wide.

The Beachcomber published the first known record of a coyote on Vashon in 1960 (VNC Wildcam Network Photo/ Camera Operator Bob Lane).

The Beachcomber published the first known record of a coyote on Vashon in 1960 (VNC Wildcam Network Photo/ Camera Operator Bob Lane).

Researchers will be able to make reliable population estimates if they have a large enough genetic database, but for now, the best tool for gauging how many coyotes live on the island is the howling survey. Since 2015, the Nature Center has conducted the annual survey around the island for one night after dark falls, howling at coyotes or playing recordings in hopes that they will call back, in an attempt to estimate the local coyote population, though no such survey took place last year due to the pandemic.

The howling surveys provide a good overview of the population, but researchers do not attempt to estimate the number of coyotes from those they hear. Coyotes have a gift for ventriloquism. Two or three can make themselves sound like a dozen or more, which helps them establish territory.

Instead, the Nature Center tries to pinpoint where the howls are coming from. This indicates the presence of a coyote pack in the area. Researchers heard two howls in the first year of the study, indicating that there were two packs on the island then. There were four responses in 2019. One was heard on Maury Island, one on the south end, one at Island Center, and another on the north end.

Although there appear to be more coyotes than in previous years, Perla said that the population on Vashon is not growing rapidly.

“That usually doesn’t happen with a predator population, anyway. It doesn’t grow like bacteria. It grows to a capacity, which I think we’re probably getting near on the island,” she said.

One possible explanation for the apparent increase in the coyote population seen in the region is not that there are actually more, Perla said, but that people are now home more often because of the pandemic and noticing the presence of wildlife around them, including coyotes.

“We are out in the woods more, taking walks here on the island. We’re looking out our windows while we’re working from home. And we’re seeing them. We’re in their space more than we have been in the past couple of years,” she said.

(Editor’s note: It’s important to be cautious around coyotes and haze those that seem to be unafraid of humans — if one crosses your path, simply make yourself big and noisy, and it should go away.)

Laura Prugh, a wildlife ecologist at the University of Washington, is working with the Nature Center on the coyote DNA project. She gave a lecture Wednesday as part of “Wild Wonder,” a Talks on the Rock series hosted by Vashon Center for the Arts about how information that is hidden within DNA, when combined with other technologies, reveals new knowledge about wildlife and how different species interact. Prugh said that the samples they gather not only distinguish individuals, much like a genetic fingerprint but that if researchers have genotypes, they can inform them about the population’s history and genetic health.

“That’s something that was really amazing with the samples from Vashon, is the genetic diversity is remarkably low,” she said. “There’s just clear evidence of what we call ‘founder effects,’ where you have a population that started with just a few individuals.”

The next step in the genetic analysis of the scat will be to identify prey items in order to tell researchers what species the coyotes are eating, which will be done using next-generation sequencing, a relatively new technique.

Prugh said she is intrigued by coyotes, which is one of the reasons she wants to learn more about them and, as a result, gain a better understanding of wildlife in the Puget Sound.

“Coyotes are just so amazingly adaptable. People have been persecuting them for so long. And they just kind of thrive in the face of persecution. So I really admire their ability to evade human attempts to kind of control them,” she said, stressing their social complexity and ecological importance. In whatever environment coyotes live in, their varied diet can have a significant impact on their prey and other species.

They can also leave an impact on people, as Prugh learned during an unforgettable brush with coyotes years ago while conducting a howling survey.

“I was always really shy to try howling when other people were around, but since I was alone, I just figured I’d go ahead and give it a go. And so I was just trying my coyote howl, and to my surprise, just right across the river for me, a pair of coyotes started howling back at me,” she said. “That was really neat to get that response. I had no idea they were there.”

The Nature Center’s next Talks on the Rock lecture, “Coyote Stories from the Field,” will be streamed at 7 p.m. March 31. Rosemary Schiano, an independent wildlife field scientist, tracker, and educator, will speak. To register, visit tinyurl.com/2vcv7cbb.