Thursday, March 26, 2009

Sea-run or Sakhalin taimen = Fish # 1 from the 1st message

Sea-run taimen from the Koppi River (mainland coast of the Sea of Japan)
There are 5 species of taimen. Four of these fish are resident freshwater predators, and this one is true anadromous fish - Sakhalin or sea-run taimen. From the sport-fisherman’s point of view there is a big difference between these species: sea-run fish is consuming most of its ration in the salt water. This is why it is often not very eager to feed in the river, and refuses the lures. Besides that, it is more careful and spooky than resident species.

One of the typical sea-run taimen rivers of the North-East of the Sakhalin Island

In Japan this fish is called ito, and its Russian names are taimen, or marine taimen. Native indigenous people of the Russian Far East call it goi. The head of Sakhalin taimen is comparatively bigger than by any of salmon species, and the jaws - much more powerful. In general it looks rather similar to steelhead salmon. It is mighty, heavy-bodied, silvery fish with numerous black dots of irregular shapes; at the head these dots are normally bigger and rounded. Belly and throat of many specimens are pink or reddish. Spawning of taimen occurs in the period of spring flood, from April (in Japan) to the end of May (north of the species range). At this time the males are bright - reddish-brown.

This big male was caught in the fall, but it still has some spawning colors from the spring spawning.

The species range is not big. Sakhalin taimen is spawning in rivers of the Russian Far East and some nearby islands (Sakhalin, Southern Kuriles, and Hokkaido), and feeding in the Sea of Japan and in the south of the Sea of Okhotsk. Many of the species populations are connected with brackish lakes, estuaries, or to the river drainages with big lakes situated on the plains. Sea-run taimen hatch in the river and spend several years (2-4, sometimes up to 7) is fresh water. After that the fish start annually to migrate out into the sea for feeding. This migration normally occurs in June. Lots of taimen come back into fresh water in September or October, but some enter the river as early as in August. Taimen movements are much more complicated and unpredictable comparing with Pacific salmon. Life cycle of Sakhalin taimen is more similar to Dolly Varden charr – this fish spends winter in fresh water, and summer and fall – in the sea. Taimen can move into the sea and back into fresh water several times during the summer.

Morphology of this species is rather different from other taimen species; some scientists separate it into different genus - Parahucho. The data of DNA analysis show a very ancient age of the species – about 40 million years. “Genetic age” of Siberian taimen is at least twice smaller. Scientific name of this fish is Hucho perryi; its species name was given in the favor of the naval Captain Perry, whose battle ship was a first American vessel visited Japan. The first specimen of this species, which came into the hands of scientists, was bought at the fish market of the Yokogama.

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