Yukon researchers unlock way to track salmon by their DNA

Yukon scientists have unlocked a way to track salmon through traces of DNA the fish leave behind in feces, mucus and flecks of skin.

Scientists can detect traces of poop, mucus and skin up to 3 weeks after fish swim past

A Chinook salmon swimming upstream. Yukon researchers have figured out how to track fish up to three weeks after they've passed through an area. (Associated Press)

Scientists in the Yukon have figured out a way to detect the presence of Chinook salmon using DNA technology.

The method is so accurate, it can detect the presence of salmon in a stream up to three weeks after a fish has migrated through.

"This is significant because it doesn't require us to actually touch or stress the salmon," said Kirstin Damude, project co-ordinator at the Yukon Research Centre. 

"We have a seven- to 21-day window to detect their DNA after they've been there, rather than having to be there on the day the salmon are there." 

Scientists filtered environment DNA (eDNA) from water samples taken from streams in the Upper Teslin, Nisutlin, and Kusawa Lake drainages last August.

The idea is to determine which tributaries are now used by Chinook salmon, and which aren't. 

Damude said the DNA comes from genetic material salmon leave behind as they migrate, such as feces, mucus and skin cells. She said the technology should be useful to environmental assessors, mining companies, and fisheries managers.

"It's for Yukon industry, fisheries management, government to figure out what questions they have that DNA can answer and how they want to use this technology," she said.

It's a good tool for understanding where species go whether it's salmon or it's other species we can apply it to."

The project was co-sponsored by Whitehorse environmental consulting firm, Hemmera. It said the technology can be applied to other fish species.

Damude and Hemmera will share results of their research at a public event Thursday at Yukon College.