Coho salmon are an anadromous species and migrate from the ocean to their freshwater natal streams to spawn. Coho salmon spawn only once and then die. This single spawning life history strategy is called semelparity. Most male coho salmon return to their natal streams to spawn after three years in the ocean, but some male only spend two years at sea and then return to their natal spawning streams.
During the spawning period, both sexes change from their blue and silver colouring to a pale grey. A peculiarity of this species is its fixed, two year lifespan. Immediately after they emerge from the gravel in the spring, the young pink fry enter the ocean and after a few days to several months in the estuary and nearshore zone, they move out into the open ocean in large schools.
There, pink salmon feed on the small and nearly invisible animals called zooplankton, especially krill, which gives their flesh the bright pink colour for which they are named. Despite their short life span and small size, the migrations of Pink salmon are extensive, covering thousands of kilometres from their home streams. During ocean feeding and maturing, pink salmon are dispersed throughout the Pacific Ocean from northern California to the Bering Sea.
During fall and winter, pink salmon spend more time in the southern parts of their range. Pink salmon are mainly caught by purse seine, gillnets or trolling gear. Troll catches are normally sold as fresh fish, while those taken by net are most often canned.
Recreational fishers generally catch pinks with the use of artificial lures. For further identifying information about pink salmon, please see our Recreational Fishing Salmon Identification pages. The best known Pacific salmon, sockeye are the most sought after for their superior flesh, colour and quality. Their rich oil content and red colour make them a favourite with the Canadian and international public.
Most sockeye in BC and the Yukon spawn in late summer or fall in lake-fed systems; at lake outlets, in lakes, or in streams flowing into lakes. Young sockeye may remain in their freshwater nursery lakes for a year or more, with some waiting until the second or third year to make their seaward journey.
Once in salt water, BC sockeye move north and north-westward along the coast. Their maturing years find them in a huge area of the Pacific Ocean extending west to approximately the International Date Line miles from the coast of Vancouver Island , north to the northern Gulf of Alaska and south to the Oregon-California border. One of the most remarkable features of sockeye is a phenomenon called "cyclic dominance". In many of the lakes of the Fraser River in particular, sockeye are abundant in one of every four years.
Sockeye can mature at ages between two and six years old but in most systems, one age group usually four-year-old fish dominates, meaning most of the offspring produced in any one "brood-year" return to spawn four years later. This year of increased population significance creates a cyclic dominance which leads to spectacular returns to the Adams River every four years.
Although there are many ideas about why this occurs, nobody knows for sure. Sockeye salmon are caught commercially with purse seine, gill nets and trolling gear. First Nations use traditional nets, weirs and gaffs; while sport fishers are able to catch sockeye with spoons or bait. Migratory pathways present the greatest availability for catch during runs from June to November.
Significant to all fishing sectors, sockeye were the first salmon to be commercially fished in the Pacific Region and were the first salmon to be canned in quantity, beginning in the s. Although ocean-going sockeye are silver in colour, with small black speckles along the body, the recollection many people have of this fish is that of the sockeye returning to freshwater to spawn. As sockeye approach their home streams, they turn varying shades of red - resulting in a brilliant scarlet fish with a green head by the time they have arrived at their point of natal origin.
It is this deep colouring, along with the rich cultural, economic and ecological history that continue to make sockeye a symbol in the Pacific Region.
Coho salmon are found throughout the North Pacific Ocean and in most coastal streams and rivers from Alaska to central California. In North America, they're most abundant in coastal areas from southeast Alaska to central Oregon. Coho salmon have also been introduced in all the Great Lakes, as well as many other landlocked reservoirs throughout the United States.
Managed under the Pacific Coast Salmon Plan : Every year, the council reviews reports of the previous fishing season and current estimates of salmon abundance.
Using this information, they make recommendations for management of the upcoming fishing season. Their general goal is to allow fishermen to harvest the maximum amount of salmon that will support the fishery while preventing overharvest of the resource and ensuring that salmon populations with low abundance can rebuild.
Specific management measures vary year to year depending on current salmon abundance, and include size limits, season length, quotas, and gear restrictions. Management of coho salmon must also comply with laws such as the Endangered Species Act. State and tribal managers use council management recommendations to shape their policies for inland fisheries, to ensure that conservation objectives are met. Managed under the Fishery Management Plan for Salmon Fisheries in the EEZ off the Coast of Alaska : All management of the salmon fisheries in federal waters is delegated to the State of Alaska , which is also responsible for managing the commercial, recreational, and subsistence fisheries for salmon in state waters.
Managers regulate the fishery based on escapement goals to ensure harvests are sustainable. They want enough salmon to be able to escape the fishery and return to fresh water to spawn and replenish the population. Salmon fishery management largely relies on in-season assessment of how many salmon return to fresh water to spawn.
Managers set harvest levels based on these returns. When abundance is high and the number of fish returning is much higher than that needed to meet escapement goals, harvest levels are set higher. In years of low abundance, harvest levels are lowered. During the fishing season, scientists monitor catch and escapement, comparing current returns with those from previous years, to keep an eye on abundance and actively manage the fishery.
Gear types, habitat impacts, and bycatch: Coho salmon are mainly harvested in commercial troll fisheries in the Pacific Northwest and Alaska. Troll vessels catch salmon by "trolling" their lines with bait or lures through groups of feeding fish.
To retrieve hooked fish, the lines are wound on spools by hand or hydraulically, and the fish are gaffed when alongside the vessel. The troll fishery produces low-volume, high-quality product.
Coho are also harvested in commercial seine and gillnet fisheries described here , both in fisheries targeting stocks of coho and as bycatch in fisheries targeting other species of salmon.
Bycatch is low and usually consists of other salmon species. Stage 1: Eggs. Each batch contains to 1, eggs. Eggs will usually hatch in early spring, and will take 50 to 70 days to hatch depending on water temperature. Stage 2: Alevin. Embryos remain and develop in the gravel, consuming an attached yolk sac for the 35 to 45 days it will need to work its way out of the gravel bed.
Stage 3: Fry. Each tiny fish, called fry, emerge to live in shallow stream margins and once old enough, defend their territory. They live in ponds, pools in rivers and streams in quiet and calm areas.
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