Known Ocean Ranges of
Pacific Salmon and Steelhead
from High Seas Tagging Research
NPAFC History Research Tagging Partners & Links Lab • High Seas Salmon Home
The users of information on the known ocean ranges of salmon and steelhead are cautioned against misinterpretation of the results from high seas tagging research. For all species, the known limits of ocean distribution are wider than the known ocean ranges of Asian and North American stocks as shown by tagging experiments. Geographic distribution of salmonids in the North Pacific Ocean varies widely with season, and is influenced by temperature, salinity, food availability, and many other physical, chemical, and biological factors that have not been examined in this summary. The use of recoveries of tagged fish to make quantitative determinations of the extent of intermingling or the degree of dominance regarding specific stocks that are present together in ocean areas is difficult. This is because of differences between stocks in the intensity of fishing effort, tag recovery effort, reporting of recovered tags, and mortality rates from tagging. For many stocks the recoveries of high-seas tagged fish reveal only their occurrence at certain times and locations in offshore waters. Despite these limitations, high seas tagging has provided significant new information on ocean ranges of Asian and North American salmon and steelhead, and is the method by which all other stock identification methods (for example, natural parasite tags, scale patterns, and genetics) are evaluated.
Pink salmon are the most abundant species of Pacific salmon. In Asia, pink salmon are distributed along the coast from North Korea and Hokkaido, Japan, to the Arctic Ocean (Yana and Lena rivers), and in North America from California to the Arctic Ocean (Mackenzie R.). Although Asian pink salmon are considered to be substantially more abundant than North American pink salmon, commercial catches of pink salmon on both continents are similar.
The known ocean range of Asian pink salmon from high seas tag recoveries extends from 58°02N in the Bering Sea southward to 38°41N in the Sea of Japan and 40°50N in the western North Pacific, and eastward to 161°55´W in the central North Pacific. The known ocean range of North American pink salmon extends from 57°10N in the eastern Bering Sea, westward to 176°30E in the central Bering Sea, to 177°38E in the Aleutians, and to 178°35W in the central North Pacific, southward to 43°30N in the central North Pacific and to 42°58N in the eastern North Pacific. Stocks originating south of the Alaska Peninsula in North America and south and west of East Kamchatka in Asia do not appear to enter the Bering Sea. Pink salmon recovered in central and southeast Alaska were more widely distributed throughout the Gulf of Alaska than pink salmon recovered in British Columbia and Washington. The known ranges of Asian and North American (Arctic, Yukon, and Kuskokwim and Bristol Bay regions) pink salmon overlap in the Bering Sea south of about 57°N, between 176°E and 172°W, and in the North Pacific south to about 43°N, between 177° E and 161°W.
Chum salmon are the second most abundant species of Pacific salmon, and the abundance of Asian stocks has always been greater than that of North American stocks. In Asia, chum salmon are distributed from northern Kyushu, Japan (at about 33°N) northward to the Siberian Arctic (Providence Bay to the Kolyma and Lena rivers). Recoveries in Asia of chum salmon (both maturing and immature) tagged at sea show Asian chum salmon to have the widest ocean distribution of any stock of Pacific salmon. The known ocean range of Asian chum salmon is remarkable, extending from 63°28N in the Bering Sea, southward to 40°07N in the western North Pacific and 41°27N in the central North Pacific, eastward to 140°00W in the eastern North Pacific, and northward to 55°49N in the central Gulf of Alaska. The large number of recoveries of tagged maturing chum salmon of Japanese origin compared to recoveries of other stocks is attributed to intense coastal fisheries and close examination of hatchery returns in Japan.
In North America, chum salmon are distributed along the coastline from California northward to the Mackenzie River in the Canadian Arctic. The known ocean range of North American chum salmon is more restricted than that of Asian chum salmon, extending southward to 44°47N in the eastern North Pacific and 45°26N in the central North Pacific, westward to 177°E along the northern side of the Aleutians, and northwest to 60°09´N, 174°30´E in the Bering Sea. Historical data from coastal recoveries of external tags (high seas tag recovery database) indicated that North American stocks originating south of the Alaska Peninsula do not enter the Bering Sea, but a few recoveries of coded-wire tagged chum salmon from Southeast Alaska, British Columbia, and Washington show that these stocks do range into the eastern Bering Sea, at least in some years.
The known ranges of Asian and North American chum salmon are broadly overlapping in the Bering Sea south of about 60°N, between 174°E and 169°W, along the central and eastern Aleutians, and in the Gulf of Alaska south to about 45°N and east to 140°W. The known ranges of maturing chum salmon of both Asian and North American origin appear to be wider than those of immature fish, but there are many fewer recoveries of chum salmon tagged as immature fish than for those tagged as maturing fish. Information from a tagging study conducted in the late 1980s by the Alaska Department of Fish and Game also showed intermingling of Asian (Russia and Japan) and North American chum salmon in the South Unimak and Shumagin Islands area.
Sockeye salmon are the third most abundant species of Pacific salmon. In coastal Asia, sockeye salmon are distributed from northern Hokkaido (where they are rare) to the northern sea coast of the Russia (Anadyr and Cape Chaplina), and the center of abundance is around the Kamchatka Peninsula, Russia. The majority of the Russian commercial salmon catch comes from two rivers, the Ozernaya River in West Kamchatka and the Kamchatka River in East Kamchatka. The high seas tag recovery database contains information on less than 100 recoveries of Asian sockeye salmon (both maturing and immature) tagged at sea. The majority of these were maturing fish recovered in Kamchatka. The known ocean range of Russian sockeye salmon as shown by tagging experiments extends eastward to 176°20W just south of Adak I. in the central Aleutians, southward to 42°29N in the central North Pacific, and northward to 57°00N in the western Bering Sea.
In North America, sockeye salmon are distributed from the Columbia River in Washington to Northern Alaska (Yukon River and Kotzebue Sound) and the Canadian Arctic (where they are rare). North American sockeye salmon are much more abundant that Asian sockeye salmon. The most abundant North American stocks occur in the Bristol Bay region of western Alaska. Recoveries of high-seas tagged sockeye salmon in North America show them to be broadly distributed across the North Pacific Ocean and Bering Sea. The known range of North American sockeye salmon extends westward to 166°51E in the western North Pacific, southward to 44°29N in the central North Pacific, and northward to 58°42N in the Bering Sea. The known ranges of Asian and North American sockeye salmon overlap primarily in the North Pacific, south to about 44°N between 167°E and 176°W. There are many fewer recoveries for immature than for maturing North American sockeye salmon, and the known range of maturing fish extends further to the southwest than that of immature fish. The known range of Bristol Bay sockeye salmon is much broader (particularly in the Bering Sea) than that of more southerly stocks.
Coho salmon are the fourth most abundant species of Pacific salmon. In Asia, coho salmon are found on Shantorskii, Hokkaido, Sakhalin, and Shimushiru islands and from the Amur River, Russia , northward to the Anadyr River (center of abundance is the Kamchatka Peninsula), and in North America from California northward to at least the Nome River on the Seward Peninsula of western Alaska (center of abundance is between Oregon and southeast Alaska). Based on catch data, North American stocks are much more abundant than Asian stocks.
The known ocean range of Asian coho salmon extends from 58°30N in the Bering Sea, south to 46°58N in the western North Pacific and 41°32N in the central North Pacific, and east to 173°31W in the central North Pacific and 179°32W in the central Bering Sea. There are few recoveries from western Alaska, perhaps because runs are too late for fisheries and processors. There is no information from tagging experiments on the distribution of North American coho salmon in the Bering Sea. In the North Pacific, the known ocean range of North American coho salmon extends from about 42°N (just off the coast of the Oregon-California boarder), northward along the coast to the central Aleutian Islands, and further offshore throughout the eastern and central North Pacific (south to 44°00N and west to 177°33E). The known ranges of Asian and North American coho salmon overlap in the area just south of the central Aleutians and further south (to about 44°N) between 177°E and 173°W.
There are interesting differences in the offshore migrations of northern (Asian and western Alaska) and southern coho salmon stocks. Northern stocks are found farther offshore (averaging four times as far from recovery sites), compared to a more coastal distribution of southern stocks. From south central Alaska to California, there are progressively fewer recoveries from offshore tag releases and more recoveries from releases in coastal waters. Travel rates also reflect this difference. Although days at liberty after tagging are about the same for both northern and southern stocks (around 50 days), Asian and western Alaska fish travel about four times faster, over 40 km/day compared to about 10 km/day for coho salmon from southeastern Alaska and southward. South central Alaskan stocks seem to be intermediate between the two extremes.
Chinook salmon are the least abundant of the five species of Pacific salmon discussed in this summary. In Asia, chinook salmon occur primarily in Russia, from the Amur River, northward to the Anadyr River (center of abundance is the Kamchatka Peninsula), and in North America, chinook salmon occur from the Ventura River, California, north to the Canadian Arctic (Coppermine River). North American chinook salmon are considerably more abundant than Asian chinook salmon.
High seas tagging experiments have provided little information on ocean ranges of Asian chinook salmon. There are only two Asian coastal recoveries of high-seas tagged chinook salmon. One was a fish released just off the coast of Hokkaido, Japan, and recovered in Japan, and the other released south of the Aleutians in the central North Pacific (172°03´W, 49°35´N) and recovered in East Kamchatka (Kamchatka River).
The known range of North American chinook salmon as shown by tagging experiments extends across almost the entire Bering Sea, north to 60°03N and west to 172°12E. In the North Pacific, the known ocean range of North American chinook salmon extends north from about 40°N (in the coastal waters just off California) and west to the waters just south of Adak I. in the central Aleutians (176°34W, 51°29N). The known ranges of Asian and North American chinook salmon overlap in the area just south of the central Aleutians between 177°W and 172°W.
Almost all stock-specific information on spatial and temporal distribution of chinook salmon within the US 200-mile zone in the northern and western Gulf of Alaska comes from recoveries of coded-wire tagged chinook salmon by the US North Pacific Groundfish Observer Program (http://www.refm.noaa.gov/observers/). Recoveries of coded-wire tagged chinook salmon show that North American stocks originating south of the Alaska Peninsula (from central Alaska to the Sacramento River, California) range northward into the eastern Bering Sea. Coded-wire tag recoveries also provided the first information on winter distribution of Yukon Territory chinook salmon in the Bering Sea, showing their distribution along the shelf break (200-meter contour) from Unimak pass and northwestward into the central Bering Sea. A recovery off the south central Oregon coast of a coded-wire tagged immature chinook salmon from the Kenai River, Alaska marks the southernmost recovery of an Alaska origin chinook salmon on the US Pacific Coast.
In Asia, steelhead are found in the Russia along the mainland coast of the Sea of Okhotsk and on the Kamchatka Peninsula, and in North American they occur primarily from central California to the Alaska Peninsula. The abundance of Russian stocks is not well known, but they are thought to be considerably less abundant than North American steelhead trout. At present, there are no reported recoveries of high-seas tagged Asian steelhead. There is no information from tagging experiments on the ocean distribution of stocks in the Bering Sea, although some steelhead do migrate in this area.
The known ocean range of North American steelhead extends in a broad swath across almost the entire North Pacific, south to 40°58N (three coded-wire tagged fish from Snake River tributaries, Columbia River basin), and west to 163°32E (one coded-wire tagged fish from the Quinault River, Washington, a distance approximately 5,370 km from the river mouth). The combined results from all high seas tag recoveries suggest that steelhead from most streams along the North American Pacific coast have similar distributions offshore. Seasonal (summer and winter) races of steelhead have broadly overlapping distributions, but have different seasonal patterns of marine distribution to accommodate the wide difference in time of return to fresh water exhibited by the two races. In the Gulf of Alaska, coastal summer steelhead appear to have a more northerly distribution than inland summer run steelhead from the Columbia River basin steelhead. Steelhead from coastal Oregon and California may have more restricted westward migrations than more northern stocks.