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█蒙城▇▄▃▂▁渔夫辨鱼之TROUT▁▂▃▄▇岸上█
1,LAKE TROUT
Salvelinus namaycush (Walbaum). In exterior colouring, lake trout vary from almost black to greyish or very light green with light coloured, irregular shaped spots. Similarly, there are variations in the colour of the flesh - from deep red to pale ivory. These differences are probably determined in part by heredity and in part by environment. Their main food is fish although smaller aquatic organisms are also eaten. Spawning occurs in the fall. Lake trout are sport fish as well as important commercially. Growth is quite slow in most water bodies in the Yukon yet twenty to thirty pound fish are not uncommon. Those living in large lakes usually grow to a larger size than those in smaller bodies of water. They will take the hook in fly fishing, with artificial lures, as well as some baits.
2,BULL TROUT
Salvelinus confluentus. Bull trout have long been confused with Dolly Varden, although we now know that they are a distinct species. They are very similar in appearance to the Dolly Varden and can only be distinguished by a few subtle differences. The easiest to distinguish physical characteristics are that Bull trout have no black spots on the dorsal fin and the eye is closer to the top of the head than a Dolly Varden. They also occupy different geographic ranges. Fish fitting this description if found in the Liard drainage are likely Bull trout, while those found elsewhere in the Yukon are likely Dolly Varden. Beware of confusing these fish with Arctic char as well.
3,RAINBOW TROUT/STEELHEAD
Oncorhynchus mykiss. A typically trout like body, rounded snout, large mouth and black spots on the back, dorsal, adipose and tail fins identify the rainbow trout. The back is bluish green to brown with white or dusky sides and underparts. Usually a light pink to vivid red distinct lateral stripe is visible. In lake populations with good food sources (generally stocked lakes in the Yukon) rainbows can reach 15 pounds in weight, but native stream fish typically weigh less than 3 pounds. Adult trout feed mainly on crustaceans (freshwater shrimp), aquatic insect larvae (caddis and black fly), mollusks and the occasional small fish. Their flesh ranges from bright orange to pale pink and is very delicious.
The steelhead is a sea-going form of rainbow trout. When in the sea, the body is mainly silvery, with a blue back. At spawning time a band of red colour develops along each side of the body. After spawning, many adult steelhead go back to the sea and some, although usually not a high proportion, return to fresh water after recuperation to spawn a second time. Females survive more often than males. The young fish live for one or two full years in freshwater before travelling to the sea as smolts from 4-10" in length. This migration takes place in the spring. Steelheads have been reported from Alsek-Tatshenshini River system in the southwest corner of the territory. They are often confused with the native trout which also exist in this watershed. However, steelhead are much larger fish, averaging better than 5 pounds. |
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