Surging chinook spawn impending baby boom

Associated Press

TOPPENISH — A large run of spawning spring chinook salmon left behind the most nests in 20 years this fall in the Yakima and Naches rivers, the Yakama Nation says.

More than 4,700 nests were found after 17,000 fish returned to the Yakima River Basin to spawn, according to the tribe, which has conducted the reproductive surveys since 1981.

While pleased with the numbers, fisheries biologists warn that circumstances for salmon aren’t always this good.

"Everything lined up, and they had good conditions throughout their lives," said Walt Larrick, a fisheries biologist for the U.S. Bureau of Reclamation in Yakima. "We saw the benefits of that here."

A series of good water years that began in 1995 — after three years of drought — contributed to the stronger run of fish. This year’s spring chinook return also was one of the best in recent memory in the basin.

In the past five years, the spring melt from above-average snowpacks in the Cascades provided high river flows that helped juvenile salmon migrate to the Pacific Ocean.

Most of the adult fish that returned this summer were spawned in the fall of 1996.

"A good water year and good ocean conditions are at least part of the environment that influenced having this run," said Pat Monk, an irrigation district biologist in Ellensburg.

Typically, the chinooks live for more than a year in fresh river water before moving to the coast, where they live in the ocean for a couple of years before returning home. Most Yakima River salmon return as 4-year-olds to spawn. Most Naches River spring chinook return at age 5, apparently a genetic quirk.

Modern fish screening and ladders and fish-management programs designed to protect salmon eggs have helped improve survival rates, Larrick said.

In 1980, a federal judge in Spokane ordered the Bureau of Reclamation to release sufficient water during the winter to keep the eggs wet. Since then, the Yakama Nation has counted the number of chinook nests each fall.

This year’s survey found 3,836 salmon nests in the Yakima River, north of Union Gap, mostly between Ellensburg and Keechelus Dam. The survey found 887 nests in the Naches River and its tributaries.

The largest previous count was in 1986, when 3,106 nests were found. the lowest count was 221 nests in 1995.

Yakima River chinook are not listed for federal protection under the Endangered Species Act. Steelhead are, but they do not begin spawning until January.