NISQUALLY (February 26, 2003) — On their third try of the day, researchers from the Nisqually Indian Tribe saw what they were looking for. “Well, there is a lot of something in their,” said Sayre Hodgson, a tribal habitat biologist. As the center pocket of their seine net comes closer to shore, several small silver flashes are apparent inside the mesh. “We have salmon,” Hodgson declares as the net is pulled in, and the juvenile salmon are quickly measured and weighed.
The Nisqually Indian Tribe is studying juvenile salmon in the Nisqually River estuary to determine how hatchery and wild fish interact in the dynamic estuarine environment. “The population of young salmon leaving the river is a mystery,” said Hodgson. “The only way to fill in that knowledge gap is to get out there and count them.”
Whether wild and hatchery salmon use the same habitat is important because fisheries managers don’t want to unintentionally harm wild stocks by releasing hatchery fish that would compete for the same resources. Nisqually River wild chinook are part of the Puget Sound chinook stock listed as “threatened” under the federal Endangered Species Act. In addition to chinook, the study is also looking at coho, chum and pink salmon and steelhead and cutthroat trout. Tribal
researchers will also be studying residence time of various stocks and what the fish eat.
Besides the impacts of hatchery fish, the study is also gathering data on the Nisqually River estuary following a major restoration project last year. The Tribe removed dikes along a 30 acre portion of the estuary, allowing the tide to recreate lost habitat. “It will be interesting to see how the salmon have reacted to the removal of the dikes,” said Hodgson.
Using seines and fyke nets, tribal crews will be collecting juvenile fish from late winter until late summer. Fyke nets are large hoop nets that act as funnels to trap swimming fish. The nets will be set at the mouths of slough channels at high tide and will be checked near low tide, allowing the researchers to see how the tide affects juvenile salmon usage in estuarine channels. “Tidal channels in estuaries are incredibly productive areas,” said Hodgson.
In addition to salmon, tribal crews last year during a pilot study found an abundance of other fish, including flounder, mountain whitefish, and several species of perch and sculpin. “The diversity of species in the estuary speaks to the dynamic nature of the habitat,” said Hodgson. “Twice a day, tides contribute nutrients to the system, making the estuary a very attractive place for fish to find food.”
The study was funded by a federal Hatchery Reform grant. With the listing of two Puget Sound salmon stocks as “threatened” under the Endangered Species Act, tribal and state managers have put a new focus on evaluating the role of hatcheries in wild stock rebuilding efforts. Hatchery Reform is a federally funded, systematic, science-driven effort to address how hatcheries can help recover and conserve naturally spawning salmon populations and support sustainable fisheries.
“Restoring habitat and finding out how salmon interact with that habitat is vital to our restoration efforts on the Nisqually River,” said Georgianna Kautz, tribal fisheries manager. “To restore wild salmon to the Nisqually River, we need to dedicate ourselves to restoring as much as we can of their habitat.”
For more information, contact:Sayre Hodgson, habitat biologist, Nisqually Indian Tribe, (360) 438-8687. Emmett
O’Connell, information officer, NWIFC, (360) 438-1181, email@example.com
Chinook Salmon Fast Facts
- Chinook salmon are the largest of the salmon, with a length ranging up to 58 inches and weights up to 135 pounds.
- Scientific name: Oncorhynchus tshawytscha.
- Common names: King salmon, tyee salmon, springs and blackmouth.
- Puget Sound chinook are listed as "threatened" under the federal Endangered Species Act.
- Chinook salmon may spend 1 to 6 or more years in the ocean before returning to their natal streams to spawn, though the average is 3 to 4 years.
- Spawning usually occurs in deep, fast water with cobble-size gravel. Average nest, or "redd," sizes can range between 43 and 162 square feet buried approximately 7 to 8 inches in the gravel. An average redd can produce between 3,000 and 7,000 eggs.
- Young chinook like to rear in side channels where they can find areas where water runs slow and cool. As they grow, the
young fish gradually move into deeper, swifter water. Once they have put on enough weight and size, chinook "smolts" migrate to the ocean.