October 30, 2006
By Tom Curet, Idaho Department of Fish and Game
You can tell by the multitudes of drift boats arriving in town
every weekend - the steelhead are back in the Salmon River.
So when did they get here? How long does it take them to get here
from the ocean? What do they do all winter? The steelhead has one
of the most fascinating and complex life histories of all
sea-going (anadromous) fish that return to Idaho to spawn.
Steelhead began migrating from the ocean back to Idaho in July.
Counting facilities on Columbia and Snake River dams allow
biologists and anglers to track the movement and timing of these
fish. A few will arrive in the upper Salmon River by late August
or early September.
Radio tracking of moving fish shows that returning steelhead are
capable of traveling up to 18 miles each day as they navigate
their way through reservoir pools. In free flowing portions of the
Snake River, they move up to sixteen miles per day.
In some years the water temperatures in the lower Snake River
reservoirs can be high enough to inhibit adult movement into the
Snake from the Columbia River. During those warm years, the
arrival of the adult steelhead can be delayed until later in the
Based on check station results over the past few weekends,
steelhead are beginning to arrive in earnest. Fish will continue
to arrive in the upper river corridor throughout the fall, and the
upstream migration will continue until winter descends on the
Salmon River country.
During most years, steelhead have been documented upstream as far
as Challis before the onset of winter. Once winter grips the
river, many of these fish will remain in the larger pools and deep
run habitats in the Salmon River, waiting for spring to arrive at
hatcheries or spawning areas.
After staging all winter, fish begin a final push upstream to
their spawning grounds when winter relents. Many fish are enroute
to either the Pahsimeroi or Sawtooth fish hatcheries or to one of
the many Salmon River tributaries to spawn. This is the time we
again see large numbers of anglers from throughout Idaho and
surrounding states in their own migration to the river for a
chance to catch one of these awesome fish.
Spring river conditions dictate how the spring fishing season
progresses. Ice jams can dominate the river corridor throughout
the winter. These ice jams, composed of hundreds of tons of
broken, angular ice, can, at times, completely block and dam
portions of the Salmon River. When the river is blocked, fish may
not be able to move upstream in the spring, and, depending on the
timing of the ice jam releases, this delay can affect the quality
of fishing upstream of North Fork.
Rain or early season melting can also make the river conditions
challenging for anglers.
The fish have really only one thing on their mind in spring -
spawning. If they have been delayed because of cold weather ice
jams or muddy water from snowmelt or rains, the fish can move
quickly from their winter staging areas to their spawning
locations. On such years, fishing can be slow and difficult. But
if late winter or early spring conditions are mild, fishing can be
good because river conditions remain very stable and clear for
The steelhead life history strategy is quite different from
Pacific salmon, such as Chinook or sockeye, which all die after
spawning. After spawning, some adult steelhead will begin
migrating back down-river in an attempt to reach the ocean again.
Before dam construction on the lower Snake and Columbia rivers,
some of these fish were able to make a repeat spawning run. But
repeat spawning is a rare today.
The eggs from fish that successfully spawn in local streams will
incubate throughout the spring, and the fry will typically emerge
in June and begin foraging for food. Juvenile steelhead will
remain in the upper Salmon River for one to five years before
migrating back to the ocean to complete their grueling life cycle.
Tom Curet is the regional fishery manager for the Salmon Region.