Colorful Tags Aid Hoh Tribe’s Coho Research

FORKS (Oct. 4, 2006)–The Hoh Tribe is using an innovative new tracking approach to find out where thousands of tiny young wild coho go to survive the winter in the Hoh River watershed.

“We know general information about adult coho returns from the use of coded wire tags,” said Tyler Jurasin, fisheries biologist for the Hoh Tribe. The tiny millimeter-long tags are inserted in the nose of young salmon to provide information about migration and survival rates. The tags are recovered in tribal and non-tribal fisheries in the ocean and river when the fish return as adults.” Those tags tell us where adults are found when they return,” said Jurasin.

“With this new tagging technology, we will know exactly where young coho spend their time in the river and where they move between summer and fall. Understanding these movements and fish use of these different habitats will allow us to prioritize habitat restoration projects. We’ll also get a better handle on winter survival.”

Beginning in late August, Hoh tribal fisheries crews used small seine nets to capture young wild coho and inject a rubbery substance in one of the fish’s anal fins before being released back to the stream. The mark, known as a visual implant elastomer, can be made into many colors to indicate exactly where the coho were captured. Barely detectable with the naked eye, the mark is fluorescent and shines brightly under an ultraviolet light. Tests have shown the mark does not harm the fish.

“Getting trained to do this work has been a good experience and it’s really going to help us see what habitats the fish prefer in the winter,” said Will Hudson, fisheries technician and Hoh tribal member.

The fish will be recaptured this fall to determine where they’ve traveled to over-winter after being marked. “Once we’ve established where different groups are in the fall, we’ll recapture them in the spring to get a better idea of winter survival and predicting adult returns. Over the years, we’ll also see how fish change their habitat use when water levels are lower or higher.”

Hoh tribal fishermen rely on the coho fishery to provide food and income in the fall and winter.

This recent trapping and tagging of coho is the first by the tribe since the 1980s. Since then, there has been significant loss of coho habitat due to forest practices and flooding.

“The information we’re gathering may allow us to better predict returns by giving us more information on the juvenile coho life cycle and it will aid us in prioritizing habit restoration projects,” said Jurasin. “We have a long list of habitats where we want to mark fish over the years,” said Jurasin.
A $52,000 grant from the Pacific Salmon Commission, (PSC) paid for the multi-year study. PSC is the implementing body of a treaty between the United States and Canada to facilitate fisheries planning and allocations between the two nations.


For more information, contact: Tyler Jurasin, fisheries biologist, Hoh Tribe, (360) 374-6737; Debbie Preston, coastal information officer, Northwest Indian Fisheries Commisson, (360) 374-5501, [email protected]