1().S 



BULLETIN OF THE BUREAU OF FISHERIES. 

 ('oiifrntfi iif ^loinarlis of l~'i hn'fji' hrouL' front. 



Food elements. 



Xuinber 

 of speci- 

 mens 

 in which 

 found. 



Fish remains 



Aranei<lii 



Hydrnchniclie ( water mites) 



Ephemerida 



orthoptera 



Hemiptera 



.Veuroptera 



Triohoptera 



Lepii-loptera (moths) 



Average 

 percent 



of 

 element. 



92.,') 

 12.4 

 •1.4 

 31.0 

 47.0 

 )3. i; 

 10.0 

 22. .5 

 16.4 



Food elements. 



Number 

 of speci- 

 mens 

 in whioh 

 found. 



Diptera 



Chironomus (larvie and pup;e) 



Coleoptera 



Hymenopiera 



Insect fragments 



Crustiicea (Entomostraca ) 



Vegetable debris 



Sand and gravel 



.\verage 

 per cent 



of 

 element. 



11. 



11.0 

 1.5.7 

 32.8 

 44.8 

 4.5 

 04.0 

 15. 5 



The rish reuiiiiiis consisted of youiit;' ^^ucker.-<. All of the speciiueiis that had 

 eaten Araneida ;uid Hydraehnldie eaiiie from Lake Creek. About one-fourth of the 

 Hemiptera were Cori.ra, and aliout one-half the Hynieiioptera were ant.s. 



One of the two speciineiis containing' Entoniostnica was taken in Upper Lake 

 and had eaten only Ditjjiuua, while the other was caught in Lower Lake and had 

 eaten lioth Dai'lniiii and ('ijcJojis. 



Nearly all tlie veg'etable material found was in the stomachs of specimens that 

 were caught with a seine in Lake Creek, just :i short distance ai)ove Cpper Lake. 

 It consisted, for the most part, of pieces of the small roots of the willows growing 

 along the creek, and was probal)ly taken by accident. 



Needham (1901) states that (Jluroiiiniuix, Currthrn. and Trichoptera were the 

 most important food elements found in the brook trout he examined. In this ca.se, 

 however, the four chief elements of animal food, named in the order of their impor- 

 tance, were Hymenoptera, Coleoi)tera, Orthoptera. and CIiironotiiKx. 



Fri/. — Twentv-six specimens of fry wen^ ol)taiiied from Lake Creek in August, 

 l'.t()-2. They were too small to be positively identified, varying in length from I to 

 li inches (2.2 to '^> centimeters). The stomachs of till except one contaiiuHl food, but 

 it was found to be in such condition that ver}' little of it could be recognized. 



Contents of stomachs of 26 fry. 



Food elements. 



Ephcmerida (nymphs! 

 Orthoptera 



Lepi<loptera ( moths i .. 



o?speH-lA-"«g« 



Food elemfiits 



of"peci-|'^™™S'^ 

 m?ns IP^^J'^^t 



in which J "' , 

 found. 1 element. 



Diptera 5 



Chironomus (larv?e and pup*) 5 



Insect fragments 23 



72 

 22 



