120 CALIKOK.MA FISH AND GAME 



Table 1. Foods Consumed by 22 Steelhead Trout from Waddell Creek, 



Santa Cruz County * 



Number found Per cent 



Class of food in 22 stomachs of total 



•Caddis-flies 557 50.54 



True-flies '. 400 36.29 



True bugs 56 5.08 



Beetles 53 4.82 



Ants, bees, wasps 13 1.17 



Miscellaneous 23 2.09 



Total 1,10 







* Fish taken August 9, 10, 1933. Average length, 4 inches ; maximum, 6.9 in. 

 minimum, 2.6 in. 



Fig. 2 8. Caddis-fly larva, Limnophilus, removed from its case. Natural 



size. 



Caddis-flics (Trichoptera) are probably tlie most important single 

 trout food in streams. They are abundant in coastal and Sierran 

 streams. A few inhabit lakes. 



The life cycle of a caddis-fly is as follows : the female flies lay their 

 eggs in water. These hatch into larvae which live from several weeks 

 to months in the stream bed and then change to pupae and emerge 

 from the water as adults, thus completing the cycle. Large numbers 

 of adults emerging from the water at the same time constitute the 

 so-called ''hatches" of anglers. "Salmon flies" which emerge in large 

 numbers at times, are members of the stonefl^y group, though emerging 

 caddis-flies and mayflies are often termed "salmon flies." 



Caddis-fl}^ larvae and pupae generall}' live in conspicuous fixed or 

 portable cases (Fig. 28) made of bits of bark, sand grains, twigs, etc. 

 The larvae may always be recognized either by their cases or by the 

 pair of hooks found at the posterior end of the body. Trout often eat 

 caddis larvae, case and all, and many stomachs contain large amounts 

 of debris from materials that formed the cases. Many anglers collect 

 caddis larvae, remove them from their cases, and fish them as bait. 



