THE FOOD OF TROUT IN YELLOWSTONE 

 NATIONAL PARK* 



By Dr. Richard A. ]\Iuttkowski 



Collaborator, Koosc-z-clf Field A\itiii-alisf. Roosczclf JJ'ikl Life 

 Forest F.vperinieiit Station. Syraeitse, A'cz^' York 



CONTENTS 



1. Introduction. 



2. Fishes and Their Environment. 



3. The Food of the Xative Redthroat Truut. 



The \A'ater Food. 

 Stone-flies. 

 ]\Iay-flies. 

 Caddis-flies. 

 ... The Surface Food. 



. . 4. Feeding Habits of the Trout. 



5. Hints to Anglers in Yellowstone Park. 

 Your Attitude. 

 How to Fish. 

 Bait and Flies. 

 Your Catch. 



INTRODUCTION 



Through the courtesy and cooperation of the Park authorities, 

 the Yellowstone Park Camps Company, and the Roosevelt 

 \Mld Life Station, the writer during the summer of 1921 was 

 enabled to make certain studies of the trout streams of Yellowstone 

 Park, particularly those of the northeastern section. The study 

 extended through four months — from June 20 to September 10, — 

 covering the critical period of the year, since the conditions during 

 these months largely determine the propagation of trout and also of 

 their natural food supply. 



* Contribution from the Roosevelt ^^'ild Life Forest Experiment Station, 

 and from the Zoological Laboratory, Lniversity of Idaho, ]\Iosco\v, Idaho. 



This is the third of a series of papers on the wild life of Yellowstone 

 National Park which has been made possible by gifts to this ^lemorial Station 

 from the joint friends of Theodore Roosevelt and of wild life conservation. 

 The initial aid for this plan came from Air. Howard H. Hays, President of 

 the Yellowstone Park Camps Company. I gladly avail myself of this oppor- 

 tunity to thank Air. Hays and Dr. Aluttkowski on behalf of the Roosevelt 

 Wild Life Station for their contribution and cooperation in this investiga- 

 tion. (Cf. also Ropscz'clt JJ'ild Life Bull.. Vol. i, Xo. i, pp. 96-99.) — The 

 Director. 



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