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Steelhead
Trout (Onchorhyncus mykiss)
Steelhead
trout are remarkable in their ability to adapt to fluctuations
in stream flows, sediment input and water temperatures,
enabling them to survive despite the occurrence of temporarily
unfavorable conditions. Southern steelhead have evolved
behavior patterns that permit them to compensate for the
fluctuations in Southern California coastal streams and
rivers. While they will return to their natal (stream of
birth) stream to spawn, they can utilize other streams when
the natal stream is not available (i.e., sand bar not breached,
lack of water). Also, steelhead can become resident trout
if water conditions preclude them from migrating to the
ocean.
Endangered Status
The southern steelhead was listed as endangered by the National
Marine Fisheries Service in 1997. The southern steelhead
Endangered Species Unit extends from San Luis Obispo County
to Malibu Creek, Los Angeles County. On July 1, 2002 the
southern boundary will be extended all the way to the U.S.-Mexico
border.
Life Cycle
Like other salmonids, steelhead must leave the ocean and
enter freshwater to spawn. Starting with the winter rains,
steelhead will enter the large coastal streams, making their
way to good habitat (abundance of gravel, clean, well oxygenated
water, abundance of insects) in smaller creeks and tributaries.
The female deposits her eggs in a small depression in the
gravel, where the male fertilizes them. After 100 days or
so, the small fish (called "fry") move from the
depression into the shallow, slow margins of the stream.
As the young fish grow, they move into deeper waters such
riffles, runs, and pools, where they have to watch for predators
such as raccoons, herons, kingfishers, gulls and crows.
Typically steelhead will remain in freshwater for 1 to 4
years before migrating to the sea. If water conditions are
right, and the proper cues are received, the young steelhead
will move downstream to the estuary where they will remain
for a period of time before beginning their oceanic phase.
Restoring Steelhead to Southern California
The key to restoring steelhead to southern California is
to provide adequate flows of cool, clean water in our coastal
streams, restore habitat on a watershed scale and provide
access to historical spawning and rearing areas. This is
easier said then done. However, private citizens as well
as state and local government are working hard to make this
happen. Citizens help through active participation in volunteer
stream monitoring and local watershed organizations. City,
county and state agencies are working to improve habitat
through riparian restoration projects, bank stabilization
projects, and finding creative solutions to steelhead barriers.
In addition, Southern Californians are voting for initiatives
that are good for our communities and the environment.
Want To Know More?
A Guide to California’s Freshwater Fishes. Bob
Madgic. Naturegraph Publishers.1999
Field Guide to the Pacific Salmon: including salmon-watching
in Alaska, British Columbia, Washington, Oregon, and Northern
California. Robert Steelquist. Sasquatch Books. 1992.
Inland Fishes of California. Peter B. Moyle. University
of California Press. 2002.
Steelhead Restoration and Management Plan for California.
Dennis McEwan and Terry Jackson. California Department of
Fish and Game. 1996. www.dfg.ca.gov/nafwb/index.html
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