Monday, July 22, 2013
DAYTON — The last man-made barrier on North Touchet River, one of the most productive fish streams in the Blues, will soon be removed.
“(W)hen I retire I will be glad to see this project completed,” fish biologist Dave Crabtree said as he led a Blue Mountain Land Trust tour up to the entrance of Ski Bluewood resort.
After the brief hike, the 68-year-old with close to three-decades of fish biology experience and one year left before retiring stood before a man-made ravine about 50 feet wide and 15 feet deep. It’s the spot where skiers would normally turn off North Touchet Road to enter the resort parking lot. And when they did, they drove over a culvert.
But not anymore.
Over the next few weeks the U.S. Forest Service will dig up and take out the last four-foot diameter culvert on the North Touchet. Once the $200,000 project is completed, what will be left is a 16-foot wide arch that will span over a natural stream and banks, thus replacing the small flume that was once a barrier to big fish.
“So it is not a straight shot because at higher flows you get real velocity going,” Crabtree said.
This fish passage project, however, is not about salmon or steelhead, but about a fish that wasn’t even considered a separate species until the late 1970s.
Bull trout were once thought to be a type of Dolly Varden, since they looked similar and were also capable of reaching lengths of three feet and weights of 20 pounds. But in 1978 it was determined that bull trout were a separate species. More research over the next decade found that there numbers were declining.
So in the 1990s the species was listed as endangered, which led to more research and a few discoveries about a fish that likes to move around.
“We were really ignorant ... We know a lot more now than we did in the early ’90s,” Crabtree said.
Using tagging methods and radio telemetry, Crabtree and other biologist soon learned that bull trout are gadabouts when it came to stream life. They often moved dozens of miles through a system of interconnected lakes and streams, depending on water temperatures, flows and spawning.
“We have tagged bull trout in Mill Creek and found them all the way out to the confluence of the Walla Walla and Touchet (rivers) ... and I have no doubt that the bull trout from the Touchet River are also moving through the area,” Crabtree said.
Decades ago, bull trout were found in all the Western states, and they could be found in 60 percent of waters in the Columbia River Basin.
Now they are down to less than half their historic range. But at least in the North Touchet River, they are thriving.
During a 2011 culvert removal project, Crabtree had the job of stunning and collecting the endangered trout to relocate them downstream while construction of a new concrete bridge took place. The biologist explained how with electric wands they carefully stunned the fish and scooped them up with nets.
What he collected was 50 bull trout from about 40 feet of river, though most were fingerling size.
“This is a very productive stream,” he said. “They get really big. I measured one in that stream that was 24 inches.”
Alfred Diaz can be reached at firstname.lastname@example.org or 526-8325.