CALIFORNIA FISH AND GAME 



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The second most important item was the two-winged or true-flies 

 {Dipt era) which formed 36.29 per cent of the total foods eaten. These 

 have a life cycle similar to the caddis-flies in that Q,g^^ larvae, and 

 pupal stages are passed in the water. Only 20 of the 400 flies eaten 

 were taken as adult or so-called "dry" flies, 380 being secured as 

 larvae and pupae below water. These larvae are readily recognized by 

 their worm-like form, lack of legs, and apparent lack of a definite 

 head (Fig. 29). Most of the true-flies eaten belonged to the family 

 Chironomidae or midges. Their aquatic stages are abundant in 

 streams and lakes, cold or warm water, and furnish one of the staples 

 in the diet of young fishes. In size they are usually from one-eighth 

 of an inch to an inch in length. Many of the larvae are often blood- 

 red in color whence they derived the name "Bloodworms." 



True bugs (Hemiptera) were the third most abundant food eaten, 

 forming slightly better than 5 per cent of their diet. Part of these 

 organisms were aquatic "water striders" that skip about on the sur- 

 faces of pools and a portion of them were strictly terrestrial forms such 

 as leaf hoppers that had fallen into the water from vegetation on the 

 banks of the stream. 



Fig. 29. Midge. Left to right, adult, pupa, larva. Six times natural size. 



Of the 53 beetles eaten, 18 were aquatic forms — diving beetles, 

 riffle beetles, etc. — and the remainder mainly ground and bark beetles 

 that had fallen into the water. The few ants, bees, and wasps found 

 in the stomachs were all typically terrestrial forms. Included in the 

 "miscellaneous" column in Table 1 are five mayfly and four stonefly 

 nymphs, one grasshopper, a few mites and spiders. 



Of the total 1102 items eaten, over 87 per cent were aquatic in 

 origin and consisted, as pointed out above, largely of aquatic insects 



