How many steelhead are migrating up and down the Nisqually River has always been a mystery.
But, this year a new camera installed by the Nisqually Tribe at a diversion dam will allow fish managers to get a handle on the population of endangered fish.
The camera is located at a fish ladder the City of Centralia’s diversion dam on the Nisqually and will take a picture of every fish swimming by.
“We’ll be able to identify the species and size of the fish as it goes by,” said David Troutt, natural resources manager for the tribe.
While every fish species will be counted, the species that most interests the tribe is steelhead. “Despite intense surveys throughout the winter and fall, we have a hard time getting a good idea of how many steelhead come back each year,” Troutt said. “The only real way to know how many there are is to count them.”
Centralia staff worked with the tribe to install the camera, lowering flow through the fish ladder for a few hours. “We’ve been working with the tribe for decades to maintain the health of salmon in the river,” said M.L. Norton, general manager of Centralia City Light. “The camera project fits perfectly with our vision of conserving the river’s resources.”
Because of glacial till, the camera will only be able to identify fish species between February and August, thankfully when the bulk of the steelhead run already is. The tribe operates a weir in the lower river during the fall that allows them to count chinook.
Nisqually steelhead are part of a Puget Sound-wide population that was listed as threatened under the federal Endangered Species Act in 2007. Nisqually steelhead populations have fallen from over 6,000 to below 1,000 in the past twenty years. This comes despite relatively good habitat for them in the Nisqually River.
“From what we can tell, steelhead have pretty good habitat in the watershed and they haven’t had much harvest pressure at all.” The tribal harvest on steelhead closed 20 years ago and sport fishermen stopped fishing for them seven years ago.
“In particular, these fish have great habitat in the upper watershed, above the Centralia diversion,” Troutt said. “The camera will give us an idea, year to year, how many fish are actually able to use that habitat.”
A possible next phase in the project would be tagging juvenile steelhead with passive tags. When the fish return in a few years, each individual could be tracked as they migrate past through the fish ladder. “Using tags would give us a level of understanding of this run that we’ve never had,” Troutt said.
“The more we know about these fish, the better we can hone our recovery efforts and the quicker we can bring them back in strong, harvestable numbers,” he said.