SEATTLE — In Kenmore, the hottest new thing is a big, dead fish — specifically one that is over 8 feet long, weighs more than 300 pounds and, at this point, is rapidly decomposing.
On Sept. 6, researchers with the Washington Department of Fish and Wildlife, the National Oceanic and Atmospheric Administration and the University of Washington responded to a report of a giant dead sturgeon on the swim beach at Log Boom Park in Kenmore.
WDFW research scientist Robert Pacunski, who performed a necropsy on the fish, said he guessed the fish couldn’t have been dead for more than two or three days.
There was little gas in it, and the meat was in “really good” condition, despite being pecked at by seagulls, he said. When he cut it open, he found eggs and a few broken clam shells in its stomach. Pacunski estimated the fish — a female — was between 60 and 80 years old.
While the fish has excited local residents and captured the attention of local TV stations, it was just another day of work for Pacunski.
“I’ve been at fisheries for 40 years. I’ve pretty much seen it all,” he said. “This is probably my third or fourth large dead sturgeon that I have sampled.”
In 2013 a large sturgeon was also found on Matthews Beach and in 1987, a whopping 11-foot long, 640 pound sturgeon was found in the lake.
While the fish is listed as a species of “greatest conservation need” under the state’s endangered species list, their presence in Lake Washington is not “particularly super rare” and white sturgeon have occasionally been observed at the Ballard Locks, WDFW spokesperson Chase Gunnell said.
However, unlike the white sturgeon in the Columbia River or the northern rivers of Puget Sound, the Lake Washington population is not well-studied and finding a dead one in such an accessible area is a good research opportunity, Pacunski said. NOAA scientists will examine the tissue’s toxicology and UW will look for parasites in the fish.
The fish had no immediate signs of mortality or injuries, and Pacunski guessed that the fish must have died of stress caused by low dissolved oxygen during a stretch of warm days. The area of Lake Washington near Log Boom Park is especially shallow, just around 5 feet deep, he said, and the fish, along with some dead salmonids on the shore, must have gotten stuck and died.
Pacunski said he responded to the report of the fish, primarily to make sure it was not a green sturgeon, which is a threatened species under the federal Endangered Species Act.
The white sturgeon, which has a cartilaginous skeleton like sharks and rays, is now decomposing a few feet away from the Log Boom Park swim beach. White sturgeon, which are bottom feeders, can travel between fresh and saltwater and can grow to weigh more than 1,000 pounds.
“They’re really ancient fish. They’re millions of years old, and they’ve been around since the dinosaurs,” Pacunski said.