Volunteers prep nursery for coho fingerlings
By JOHNNY WALKER
North Kitsap Herald Correspondent
March 16, 2012 · Updated 2:47 PM
POULSBO — Armed with waders, shovels and sandbags, volunteers organized by the North Kitsap-Bainbridge chapter of Trout Unlimited were hard at work Sunday preparing a salmon-rearing pond off Big Valley Road to receive new coho fingerlings in April.
According to chapter spokesperson Bill Stock, the clean-up of sediment and debris from the 30-by-16 foot pond had not been addressed for about 10 years. Combined with the improvement of a concrete spillway, the maintenance work is expected to contribute to a healthier ecosystem for salmon fingerlings as they mature to an eventual release date, sometime in December.
Known as Dove Pond, the 6-foot-deep manmade rearing and settlement ponds were named collectively after the 1915-era dairy farm they were built on.
The project was primarily intended to help prepare for salmon reintroduction but was also sensitive to the area’s natural environment. According to Stock, mechanized equipment was avoided in favor of manual labor to avoid unnecessary damage. The sediment was also recycled.
“Sediment and debris will be removed from the pond but most of the organic material will be put back where it came from,” said Stock, referring to the high banks around the area. “Some debris and mud will also be used to fill sandbags to create splash ponds in the tributary and ease the path for migrating fish.”
While the work was difficult in the deep mud, volunteers took it in stride.
“I definitely think it is a good cause and worth my time,” said 17-year-old Jared Witt, a Poulsbo resident and volunteer.
According to Stock, the coho fingerlings destined for Dove Pond had not been identified but are likely to come from the Suquamish Tribe’s Cowling or Grovers Creek hatcheries. When the time comes, up to 1,200 coho, also known as silver salmon, will be seeded to the pond to begin the migration and spawning lifecycle.
Patrick Allen, Poulsbo resident and vice president of the chapter, estimates that after introduction only 40-50 percent of the fingerlings will survive to December. Raccoons, herons, bear and other predators frequent the area and will take a natural toll on the fingerlings.
“Cutthroat trout also use the tributary and will gorge themselves on the young salmon,” Allen said. “They will work their way into the pond and feed on the smaller coho fingerlings.”
In December, the downstream spillway on the pond will be opened and the young fish will be free to work down the tributary on their own volition. After negotiating a narrow and difficult culvert on Big Valley Road, they can then swim to Dogfish Creek’s headwater stream. From there, they will slowly work to the Liberty Bay estuary where they will acclimate to salt water.
Three years after release, only about 1-5 percent of the salmon are expected to survive for the return trip up the Dogfish to their headwater spawning area.
“The current run is not a sustainable run without continual reintroduction,” Allen said. “We continue to watch for prioritization to correct fish passage blockage, such as the Big Valley Road culvert, to improve survivability.”
The overall mission of Trout Unlimited is to conserve, protect and restore cold-water fisheries, their watersheds, and ecosystems as a means of maintaining our quality of life.