This is one of three Fishopedia entries on salmon. The others are Atlantic salmon and farmed salmon. The entry on Atlantic salmon includes a brief description of the biology of salmon, which more or less applies to Pacific species as well.
Pacific salmon has always been far more abundant than Atlantic salmon. The Pacific wild salmon catch averages 900,000 tonnes a year; that of wild Atlantic salmon at its peak was only 12,000 tonnes.
The welcoming committee
Pacific salmon is a more complex genus than Atlantic, with five species described below plus two Asian species. Their life cycle is pretty similar to that of Atlantic salmon (described here) save that upon returning to their native rivers the welcoming committee includes seals, whales and bears as well as fishermen. Some of those who get past this lineup then make an almost inconceivable journey to their spawning spot: the uppermost spawning pools of the Salmon River in Idaho are a thousand river miles from and seven thousand feet above the sea (by comparison, the Atlantic salmon has it easy). Chinook salmon weighing up to 15kgs are still regularly caught in the Salmon River.
|Name||Latin Name||Catch 2018*||Mean Catch†||Farmed||Hatchery Releases‡|
|Chinook or king salmon||Onchorynchus tshawytscha||4,500||10,400||10,000||260|
|Sockeye or red||Onchorynchus nerka||172,000||152,000||none||250|
|Coho or silver||Onchorynchus kisutch||25,000||24,000||110,000||92|
|Chum, dog or keta||Onchorynchus keta||273,000||323,000||none||3,000|
|Pink or humpback||Onchorynchus gorbuscha||592,000§||406,000||none||1,350|
* in tonnes. Annual Report of North Pacific Anadromous Fish Commission 2018
‡ millions of fish
§ It is normal for the catch of pink salmon to swing wildly around the average, usually in alternate years.
... Not all equal
|Name||Route||Large specimen||Fat content*||Price||Years at sea|
|Chinook||Alaska to California||40kg / 100cm||11g||$13||5-8|
|Sockeye||Kamchatka and Alaska||6kg / 70cm||9g||$3.50||2-3|
|Coho||Kamchatka and Alaska||15kg / 90cm||6g||$3.10||1.5|
|Chum||Japan to Alaska||5kg / 85cm||4g||$1.95||5-7|
Kamchatka and Alaska
|6kg / 65cm||4g||$1.05||1.5|
* per 100g. For comparison: Atlantic salmon: wild - 6g, farmed - 13g
† Alaskan quayside price / kg 2018. Alaska Dept of Fish and Game
|Alaska Historical Society|
The supernatural quantities of salmon amazed white settlers arriving on the American Pacific coast and were immediately recognised as a serious business opportunity. Efforts to preserve the fish and export it to the burgeoning population on the east coast and around the world commenced immediately but with little success until canning arrived in the 1860s. A huge industry developed immediately with hundreds of canning factories and tens of thousands of employees. By 1880 20,000 tonnes of the total salmon catch of 27,000 tonnes was processed into 30 million 1lb cans. By 1917 production hit 430 million cans. As the industry pillaged the salmon and the catch was depleted in Oregon and Washington, the industry moved up towards Alaska, which contributed half the total production.
I estimate that current US and Canadian production of canned salmon stands at about 200 million lbs, much of the volume having been displaced by frozen salmon.
The chart shows that all is probably well for Pacific salmon and indeed the total catch has more than doubled over the last 50 years. The stock is guarded during its seagoing phase by the North Pacific Anadromous Fish Commission which was established in 1992 to protect salmon beyond the 200 miles zones of its members: Japan, Korea, Russia, Canada and the USA. This itself was a followon from The Pacific Salmon Treaty of 1985 which formalised management between Canada and the USA of the fishing of salmon which crossed each country’s shores on its way to the other’s rivers.
The North American and Asian fishing efforts each make about half of the total catch although the majority of the more valuable species are caught by the Canadian and US fleets.
... with a lot of help
But this is not entirely the bounty of nature. As can be seen from the hatchery release column in the first table, astonishing numbers of young salmon are released from hatcheries every year- three billion chum salmon, well over a billion pink salmon and 250 million each for chinook and sockeye. Hatcheries were first established in the late nineteenth century but they operated on only a small scale until the 1970s when the decline in the commercial catch (see chart) suggested a bigger effort was needed. 700 million hatchery fish were released in 1968, 4 billion in 1982 and the figure since 1990 has stood at 5 billion a year. Ten hatchlings are released for every adult salmon caught. The rest keep other sea creatures well-fed.
Success rate 10%
In natural habitats the survival rate of wild salmon eggs to become “fry” – infant salmon about 4cms long - is about 10 per cent. Predation, bad weather, disease and shortage of food account for the rest. In a hatchery, however, over 90 per cent of eggs grow into fry. There are hundreds of hatcheries up Canadian and west coast US rivers and on the those of the eastern Pacific. The reason hatcheries focus on chum and pink salmon despite their being the less valuable species is that these two go to sea when they are just a few days or weeks old, whereas the other species need up to 18 months in freshwater, growing into much larger fish. As any hatchery has a fixed number of water tanks, it can produce many more pink and chum than other kinds. These pictures are from a video made by Geoff Grognet for the The Chapman Creek Hatchery in British Columbia, Canada.
|Stage 1||6 months later||5 minutes later|
Success rate 90%
Hatchery salmon are normally “thermally marked” during their egg stage by changing the water temperature up and down by a few degrees. This leaves a microscopic but distinct pattern on the tiny earbone (“otolith” - pictured) which can be examined by scientists when – two or five years later - the fish is caught. Thus the contribution of hatchery fish to the total salmon catch is known precisely. For example, 34 per cent of the Alaskan salmon catch in 2018 originated in hatcheries.
Not everyone is happy about hatchery fish. Just like wild salmon, hatchery fish seek out the tributary of their birth, but they don’t all succeed and may end up in another river down the coast where there is no hatchery and wild fish predominate. They therefore compete with the wild fish. Anglers seeking prize salmon are not too impressed if their chinooks are crowded out by pinks. Hatchery fish are not selectively bred for size or any other trait, thus maintaining genetic diversity although according to some critics, not enough of it. The management of hatcheries of old has been characterised as “Just tell me how many salmon you want”. This attitude has been reformed over the last 20 years to limit their impact on wild populations.
The Fish Society's Pacific salmon
We did not traditionally sell Pacific salmon because who needed it when there were ample supplies of wild Scottish salmon? However, as these dried up (see Atlantic salmon), we cast around for quality wild Pacific salmon. In 2019, we launched sockeye and in 2020, king salmon.
- Hatchery video copyight Geoff Grognet