Small fry return through locks as big fish

One of the memorable tourist attractions of Seattle lies on the very edge of Ballard, yet you'd be surprised how many residents have never visited, or even know about it. I'm talking about the Hiram M. Chittenden Locks on the Lake Washington Ship Canal.

But the main sight, right now, is not the locks but at the fish ladder, which allows salmon and steelhead to bypass the locks and climb up to freshwater to spawn.

Park ranger Dennis Graham, with the U.S. Army Corps of Engineers, told me that the Corps first built a fish ladder in 1917, with 10 steps or weirs, when they built the Chittenden locks at the site of what was then a tidal stream running out of Lake Union.

In 1976 the Corps built a new and improved fish ladder with 21 steps instead of the former 10, making it much easier for the migrating fish to return.

With the new ladder an increased flow of freshwater, called attraction water, was able to get through. The downstream movement of water attracts fish to the ladder, as does the "smell" of the water from the salmon's birthplace stream.

It's now that time of year when the salmon are beginning to make their annual return in their circle of life. The fish ladder's viewing windows are filled with returning big salmon.

What's a fish ladder?

It's a series of linked, stepped pools, each one a foot or so higher than the one preceding. Fish swimming through the river or watercourse use the ladder to get around falls, dams, locks and other barriers that impede their progress to reach their birth waters.

Salmon, and a few trout, belong to a group of fish that are anadromous - fish that journey from salt- to freshwater to spawn. The Chittenden ladder is one of the few in which the fish not only get around an obstacle but also change from salt- to freshwater.

Four species of migratory fish are the major users of this fish ladder. The sockeye are the biggest run, with some fish beginning to show up in June and running through until October. The main sockeye run occurs in July.

Chinook or king, the largest of salmon, run from July through November, with the main part of the run coming through in late September. The steelhead (seagoing trout) run is between March and April.

Each adult female lays several thousand eggs, yet less than one egg per 1,000 survives to return as a spawning adult salmon.

Sockeye fry (immature fish) move into lakes soon after hatching and stay there from one to two years. They then travel to the sea, where they remain for three or four years before returning.

Chinook enter the ocean before they are 1 year old; they, too, spend three or four years before returning.

Coho migrate to the sea after one or two years, but they remain the least time in saltwater, only 18 months, before they return to spawn.

Counting fish

At the ladder I talked with Nancy Gleason, of Washington State Department of Fisheries and Wildlife, who was counting salmon as they swam through the ladder.



"Here at the locks, we share fish-counting duties," she told me, "with the Muckleshoots. We count fish 10 minutes each hour, 16 hours per day from June 12 through Oct. 2 each year. Since June 12, approximately 24,000 sockeye have swum around the locks.

"The Lake Washington run of sockeye each year," she continued, "is the largest run in the lower 48 states, with over 400,000 sockeyes swimming through the fish ladder here at the locks."

The Chinook run is much smaller, with more than 7,000 fish in 2003, and the coho run is smaller still, numbering more than 6,000.

A collaborative effort

I have a source within the Department of the Interior in Washington, D.C., who tells me that the Muckleshoots raise more fish than the state Department of Fisheries and Wildlife.

He also tells me that the Muckleshoots and 19 other tribes around Puget Sound and the Olympic Peninsula are raising and releasing approximately 50 million salmon and steelhead a year back into the waters.

The co-management responsibilities between the state and the Indians came about as a result of the Boldt Decision, which allowed the Indians to take 50 percent of the returning salmon. As the state runs out of money, the Indians are forced to do more management.

They have since formed the Northwest Indian Fish Commission in Olympia to oversee and manage the work of the 20 tribes involved.

They have a website - www.nwifc. wa.gov - that is quite interesting.

Freelance columnist Gary McDaniel can be reached via e-mail at needitor@ nwlink.com.

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