34 



FISHES OF AUSTRALIA. 



The Rainbow Trout is a very hardy fish, beautifully- 

 coloured, and is very game ; consequently it is an ideal 

 sporting fish. It attains a weight of 5 to 6 pounds, or even 

 more ; examples of 2 or 3 pounds' weight being common. 

 The food consists usually of worms, insect larvae and aquatic 

 insects. In its native waters, it is a great enemy of the 

 Quinnat Salmon (which is a much bigger fish, of course), 

 as it is most destructive to the eggs of that species, devour- 

 ing them in large numbers. Although it usually is found 

 during the whole of its life in fresh-water, under certain 

 conditions it is known in America to descend the rivers 

 and pass out to sea, returning again at the breeding season. 



The colours of the Rainbow Trout are as follows :- 

 Upper parts, greenish-blue, often purplish ; the sides more 



Fig. 12. RAINBOW TROUT (Salmo irideus). 



or less silvery, and profusely spotted with small black spots, 

 these being most numerous above the lateral line. The head 

 and the dorsal, caudal and adipose fins are also black-spotted. 

 (Sea-run specimens are uniformly silvery, without black 

 spots.) In the breeding season, the broad crimson band 

 on the sides becomes very much brighter. The jaws of the 

 male, during the breeding season, though not greatly dis- 

 torted as in a number of the Salmonidte, are very much 

 larger than those of the female. 



In regard to the sporting qualities of this fish, I may 

 state that in America, taking its weight into consideration, 

 it is thought to be a greater fighter than any other trout. 

 Messrs. Jordan and Evermann, the eminent authorities on 

 fishes in America, writing of this species, state that: "In 

 beauty of colour, gracefulness of form and movement, 

 sprightliness when in the water, reckless dash with which 



