Pink salmon or humpback salmon (Oncorhynchus gorbuscha) is a species of anadromous fish in the salmon family. It is the smallest and most abundant of the Pacific salmon. The scientific species name is based on the Russian common name for this species gorbúša (горбуша), which literally means humpie.
In the ocean, pink salmon are bright silver fish. After returning to their spawning streams, their coloring changes to pale grey on the back with yellowish-white belly (although some turn an overall dull green color). As with all salmon, in addition to the dorsal fin, they also have an adipose fin. The fish is characterized by a white mouth with black gums, no teeth on the tongue, large oval-shaped black spots on the back, a v-shaped tail, and an anal fin with 13-17 soft rays. During their spawning migration, males develop a pronounced humped back, hence their nickname "humpies". Pink salmon average 4.8 pounds (2.2 kg) in weight. The maximum recorded size was 30 inches (76 cm) and 15 pounds (6.8 kg).
The native range of the species is in the Pacific and Arctic coastal waters and rivers, from the Sacramento River in northern California to the Mackenzie River in Canada; and in the west from the Lena River in Siberia to Korea and Honshu in Japan. In North America pink salmon spawn from the Mackenzie River in the Arctic to as far south as tributaries of Puget Sound, Washington. Pink salmon were introduced into the Great Lakes of North America, where there are now self-sustaining populations, and in Iran. In Europe, pink salmon have been periodically introduced to rivers of the White Sea and Barents Sea basins in Russia since 1956. Stray fish from these rivers have been encountered ascending to rivers also in Norway, Sweden, Ireland, Great Britain and Iceland, and in Norway even self-sustaining populations have been observed.
Pink salmon in their native range have a strict two year life cycle, thus odd and even-year populations do not interbreed. In the state of Washington, Pink salmon runs occur on odd years. Adult pink salmon enter spawning streams from the ocean, usually returning to the stream where they originated. Spawning occurs between late June and mid-October, in coastal streams and some longer rivers, and in the intertidal zone or at the mouth of streams if hyporheic freshwater is available.
Pink Salmon - by Alaska Dept. of Fish & Game
Pink Salmon - by NOAA