MILL CREEK — It was a gruesome scene that awaited morning rush-hour commuters.

Seven beavers were struck and killed by cars Tuesday on a busy Mill Creek thoroughfare, forcing drivers to weave around the carcasses.

Sgt. Randy Lambert

had never heard of anything like it in his 35 years as a state Department of Wildlife agent.

Biologists suspect that heavy rains ruined the beavers’ lodge and they went looking for new digs.

Each beaver was run over in a roughly 50-yard stretch near the intersection of 132nd St. SE and 35th Ave. SE.

“I was wondering, ‘What in the world happened?'” said Matt Posivio, who spotted the dead beavers while driving to work. “To see so many of them. My first thought was, ‘I hope this isn’t foul play.’ “

The sheer size of the beavers, which average around 40 pounds as adults, made it look like a road strewn with dogs, he said.

Lambert consulted biologists, who speculate that the beavers’ old home gave way after it was drenched by hard and persistent rains. In two weeks, the Everett area absorbed more rain than it usually gets during a typical March — often one of the wettest months of the year.

“It could have flooded them out,” Lambert said. “I’m envisioning that’s what happened.”

Adult beavers measure more than 3 feet long including their broad, flat tails.

“I don’t think it’s possible to hit something like that and not know it,” Mill Creek police Sgt. Ian Durkee said.

Several drivers must have hit the beavers, whose carcasses were scattered across different lanes.

Police were called to the intersection and someone from a public works crew removed the carcasses.

There is a healthy beaver population in Washington, with many of the animals quietly living in the suburbs, wildlife officials said. They speculate that the beavers, which have dark fur and are built low to the ground, were trying to cross the road under early morning darkness and could not easily be seen by drivers.

Dead beavers have been found along the city’s streets in the past, but never more than two at a time, Durkee said.

There are wetlands nearby and “that intersection is pretty notorious for flooding badly when the rains come down pretty heavily,” he said.

A family of beavers can build and maintain one or more dams in their territory, according to the state wildlife department. They live in colonies usually made up of an adult breeding pair and their kit offspring.

Even so, it’s unusual for that many beavers to be moving together, said Dave Pehling, a zoologist with the Washington State University Extension Service.

In beaver colonies, older ones tend to migrate away and look for their own area, Pehling said.

“Beavers usually don’t travel in a bunch,” he said.

Regardless of how unusual it was, Posivio said the image of the dead beavers was a tough way to begin his work day.

“It was just a sad thing to see,” he said.

Eric Stevick: 425-339-3446; stevick@heraldnet.com.