realized by the superintendent of the United States Fisheries Station at 

 Afognak, Alaska, more than twnety years ago T/hen he v^ote that: "The run of 

 bluebacks has been on the decline for the past four- years', and i€ stpes are 

 not taken soon to retard the Dolly Varden trout from follovjing the salmon to 

 the spawning beds, they xvill in a short time become extinct," 



Ecological Limits on Fish Abundance 



Most anglers fail to realize that for each body of vvater there is a 

 limit beyond which the fish population cannot go. This limit may be expressed 

 either in pounds or numbers; consequently if there are many fish present, they 

 vjill of necessity be small. It has been said by experienced fish culturists 

 that there is no vjay in vjhich large numbers of good-sized trout can be grown on 

 natural food alone, lii/hen the fish-carrying capacity of a stream has been 

 reached there must be an alteration of the stream ecology viith an increased 

 food supply if more fish or more pounds of fish are to survive, and this may 

 be impossible of achievoment. 



FOOD OF BIRDS COlOaiNSD B": i^-GLERS 



Only by examination of storaach contents or of regurgitated food items 

 can one be sure of the kinds of food eaten by most species of birds in the i-Jild 

 state. Because fish-eating birds are aquatic or wfeami -aquatic and capture most 

 of their prey vjhen at least partially submerged, the neod is all the greater 

 for laboratory exsimination to identify their focd,^ The Fish and Wildlife 

 Service made such studios of the food of fish-«atKig birds, many in such numbers 

 as to represent all times of the year c.s \13ll as a vide variety of localities. 

 The results, T,Jhich present a fair picture of their food tendencies, are the 

 basis of the following accounts of tho food of the principal species. 



Pelicans 



A number of investigations have boon conducted in response to complaints 

 of deprodations by brov;n pelicans. During the V/orld 'ilq^x there was a meat short- 

 ago and ^A'hen our people were called upon to eat more fish, pelicans, as Vijell as 

 many other fish-eating birds wore vigorously condemned because the cry went up 

 from fishermen and fish dealers that the inroads made by fish-eating birds, 

 particularly the brown pelican, made it impossible for them to make good catches. 

 Extermination of the bird was urgently demanded. Consequently investigations by 

 the Federal Government, State departments, .societies, and museums ensued. The 

 Louisiana coast from Pearl River on the east to Sabine River on the west was 

 thoroughly investigated, pelicans collected, and their nesting colonies critical- 

 ly examined. The results brought an almos-t^oomplete vindication of the birds. 

 In this particular area 97 percent of the fishes taken were menhaden and 3 per- 

 cent silversides, not a single food fish being found. A similar detailed 

 investigation in Florida showed that menhaden comprised 91,4 percent of all 

 food taken, while fishes valued as food by man made up only 1,1 percent of the . 

 total. In further studies, carried on by the National Association of Audubon 

 Societies in Tampa Bay, 1,276 fishes were picked up at a pelican colony. Of 

 these, only 39 vjere food fishes. At another Florida colony, 3,428 fish speci- 

 mens were collected, of i-hich only 27 were of marketable species and those were 

 not of highly prized varieties. 



The interesting and attractive white pelican of the T7est, the very 

 existence of which only a few years, ago, was seriously threj^tened, iikowise. 



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