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By Noah Hall
Geographic Range
Currently, range is limited to Pacific Ocean, Columbia and Snake Rivers, and Redfish Lake (Idaho).
Biogeographic Regions:
nearctic 
(native ); pacific ocean (native ).
Habitat
At different life stages, sockeye inhabit both fresh and salt water. They need loose gravel to make redds, and juveniles especially need unobstructed river passages and a strong water flow.
Aquatic Biomes:
lakes and ponds; rivers and streams; coastal .
Reproduction
Sockeye Salmon, like all Pacific salmon, are anadromous. Though they live in the ocean, they return to fresh water to spawn. Adults enter the Columbia River in June and July, ascending the river at about 13 miles per day. Those individuals that survive arrive at Redfish Lake in August, and there they take four to eight weeks preparing to spawn. It is then that the fish develop a reddish orange body color, the females swell with mature eggs, and the males develop hooked jaws. In October, the females construct nests (redds) in a gravel depression for 50 to 100 eggs. The eggs are then fertilized by the male. This process is repeated until the female has deposited about 2000 eggs. The adults die within a few weeks of spawning. The eggs incubate until April or May, then hatch, and the young begin to feed. One or two years later, the smolts begin to migrate to the Pacific, where they live for one to three years before returning to the river.
Key reproductive features:
semelparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (external ); oviparous .
Behavior
Pacific salmon have an incredible ability to find and return to their home river. The salmon are guided home by the characteristic odor of the parent stream. It is during the smolt's migration that the smell is imprinted. The sun may also play a role in directing the salmon.
Key behaviors:
natatorial ; motile .
Food Habits
As young, begin to feed on attached yolk sacs, then plankton. Later, become predators and feed on insects, invertebrates, and other small fish. They do not feed once they return to fresh water, living off their accumulated body flesh.
Economic Importance for Humans: Negative
None, unless the status of the salmon cause dams to be regulated or not built. Many dams were required to develop systems to allow the fish to migrate.
Economic Importance for Humans: Positive
The economic benefits of the sockeye are clear. The fish is a delicious food source, and any harvesting (of stocked fish) is lucrative. The fish are also a favorite of sport anglers, who pay large fees to catch (and release) this exciting sport fish. Also, the existence of the fish and the remarkable river migration brings tourism to many Pacific northwest communities.
Conservation Status
IUCN Red List: [link]:
Not Evaluated.
US Federal List: [link]:
Endangered.
CITES: [link]:
No special status.
State of Michigan List: [link]:
No special status.
Listed as a federally endangered species on November 14, 1991. The constuction of dams on the lower Snake River is a major threat to the species because of its unique migrating pattern. In 1989, only 2 fish returned to Redfish Lake. None were seen the following year and only 4 in 1991.
Other Comments
The sockeye are very similar to kokanee salmon, which do not migrate and spend their entire lives in Redfish Lake. The two species do not interbreed.
Contributors
Noah Hall (author), University of Michigan.
