Salinas River (California) - Ecology

Ecology

The Arroyo Seco is the only major Salinas River tributary which remains un-dammed and supporting one of the most persistent remnants of the threatened Central Coast Steelhead trout (Oncorhynchus mykiss) that spawn in the Salinas River watershed. It is also an important middle link for salmon migrating from the Salinas River to Tassajara Creek and other tributaries. A 2001 assessment of steelhead habitat of the Arroyo Seco and its Piney Creek tributary found high potential for steelhead population restoration. Estrella River also remains un-dammed.

Other tributaries of the Salinas River that support steelhead include Paso Robles Creek, Jack Creek, Atascadero Creek, Santa Margarita Creek and Trout Creek in the upper reaches of the River. It can take over ten days for the steelhead from the upper part of the watershed to migrate to the Pacific Ocean near the City of Marina on Monterey Bay. From there, the steelhead migrate to the area west of the Aleutian Islands before returning to the spawning grounds in the tributaries of the Salinas River.

Father Pedro Font described salmon in the Salinas River (Rio de Monterey) on the de Anza Expedition in March, 1776:"...there are obtained also many good salmon which enter the river to spawn. Since they are fond of fresh water they ascend the streams so far that I am assured that even at the mission of San Antonio some of the fish which ascend the Rio de Monterey have been caught. Of this fish we ate almost every day while we were here." This meant that salmon would traverse the Salinas River and up the San Antonio River to end up near Mission San Antonio.

After depletion by 19th century fur trappers, California golden beaver (Castor canadensis subauratus) have expanded their range from the Salinas River mouth at least to its San Antonio River tributary below the reservoir.

The upper Salinas River and its tributaries used to host large runs of steelhead trout and Chinook salmon. However the salmon were extirpated by 1915, largely by dams which prevented fish passage to spawning runs, and the steelhead are reduced to mere remnant populations.