Other names: steelhead trout, sea-run
rainbow trout
Average size: 8-11 lbs, up to 40 lbs
Steelhead and rainbow trout are the same species, but rainbow
are freshwater only, and steelhead are anadromous, or go to sea.
Unlike most salmon, steelhead can survive spawning, and can spawn
in multiple years.
Spawning
Steelhead spawn in the spring. They generally prefer fast water
in small-to-large mainstem rivers, and medium-to-large tributaries.
In streams with steep gradient and large substrate, they spawn between
these steep areas, where the water is flatter and the substrate
is small enough to dig into. The steeper areas then make excellent
rearing habitat for the juveniles.
Like chinook, steelhead have two runs, a summer run and a winter
run. Most summer runs are east of the Cascades, and enter streams
in summer to reach the spawning grounds by the following spring.
A few western Washington rivers also have established runs of summer
steelhead. Winter runs spawn closer to the ocean, and require less
travel time.
Rearing
Steelhead fry emerge from the gravel in summer and generally rear
for two or three years in freshwater, occasionally one or four years,
depending on the productivity of the stream. Streams high in the
mountains and those in northern climes are generally less productive.
Due to their faster growth, hatchery steelhead smolt at one year
of age.
Fry use areas of fast water and large substrate for rearing.
They wait in the eddies behind large rocks, allowing the river to
bring them food in the form of insects, salmon eggs, and smaller
fish.
TERMS
Alevin |
The lifestage of a salmonid between egg
and fry. An alevin looks like a fish with a huge pot belly,
which is the remaining egg sac. Alevin remain protected
in the gravel riverbed, obtaining nutrition from the egg
sac until they are large enough to fend for themselves in
the stream. |
|
|
Anadromous |
Fish that live part or the majority of
their lives in saltwater, but return to freshwater to spawn.
|
|
|
Emergence |
The act of salmon fry leaving the gravel
nest. |
|
|
Fry |
A juvenile salmonid that has absorbed its
egg sac and is rearing in the stream; the stage of development
between an alevin and a parr. |
|
|
Kype |
The hooked jaw many male salmon develop
during spawning. |
|
|
Parr |
Also known as fingerling. A large juvenile
salmonid, one between a fry and a smolt. |
|
|
Smolt |
A juvenile salmonid which has reared in-stream
and is preparing to enter the ocean. Smolts exchange the
spotted camouflage of the stream for the chrome of the ocean.
|
|
|
Substrate |
The material which comprises a stream bottom. |
Trout
& Salmon Identification Guide [PDF]
|