Tribal fishery biologists are hoping tags in juvenile salmon can offer evidence of the effectiveness of habitat restoration on Ohop Creek.
Nisqually Indian Tribe researchers will use passive integrated transponder tags to track juvenile salmon as they move from the Nisqually River into the creek.
Two years ago, the tribe, the Nisqually Land Trust and the South Puget Sound Salmon Enhancement Group restored a mile of the creek by building a new channel. The project cost about $1.5 million for engineering, administration and construction services.
The new channel stays cooler for salmon and includes logjams that benefit both juvenile and adult fish. It is visible at the state Route 7 bridge as you travel across the Ohop Valley.
“Ohop was transformed from a straight, deep ditch to a shallow, meandering stream that is good for salmon,” David Troutt, natural resources director for the tribe, said in a prepared statement.
The microchips, about the size of a grain of rice, were inserted into almost 1,000 juvenile salmon captured in the upper reaches of the creek. The tagged fish will then be released and tracked as they swim through restored and unrestored stretches of the creek.
“Basically, what we’re trying to figure out is how young fish are using the restored parts of the creek,” Troutt said in his statement. “Are they hanging out in the restored section longer? This information will help us see how successful we were and decide how we can best restore the rest of the creek.”
The plan, being developed jointly with local landowners, calls for the restoration of seven miles of Ohop Creek.
“This initial phase will teach us a lot about how habitat restoration might look like throughout the valley,” Troutt said.
Ohop Creek is one of two major Nisqually tributaries that can produce sustainable populations of chinook.
“Because there are only a few places other than the mainstem of the Nisqually River where chinook spawn, increasing the quality of habitat in those places is important,” Troutt said.
Nisqually River chinook are part of the Puget Sound chinook population listed as “threatened” under the federal Endangered Species Act.
Researchers also expect to see a big benefit to coho salmon, which return in very small numbers to the Nisqually watershed, Troutt said. Coho densities tripled after a similar project on the nearby Mashel River.
“Bringing salmon runs back to the Nisqually means restoring and protecting habitat where we can,” Troutt said. “Ohop Creek is a huge opportunity for us to do a lot of good for salmon.”