UNITED STATES 



Elsewhere, as in Alaska, fishes of 

 V'arious kinds are important in the 

 diet of the bald eagle. This fact 

 was brought out even by the limited 

 series of 31 stomachs collected in tlie 

 United States (p. 24). Fish were 

 present in 18 of these stomachs, of 

 which an indeterminate portion was 

 carrion in origin. Among the kinds 

 identified were perch, goldfish, cat- 

 fish, and eels. 



Indication of tlie preference of 

 the bald eagle for fish in the ^Middle 

 Atlantic States may be gained from 

 the data set forth in table 4. Of the 

 fishes, the catfishes Ameiurms and 

 Ictalurws were most frequently en- 

 countered, while the birds were best 

 represented by waterfowl, particu- 

 larly ducks. Feathers of the bald 

 eagle in the stomachs may have been 

 indicative of cannibalism or exces- 

 sive preening of its own feathers by 

 the eagle involved. The seeds of 

 persimmon probably were in the 

 stomach contents of some prey on 

 which the eagle had fed. 



The importance of fish in the diet 

 of the bald eagle was clearly sliown 

 in the observations by Dr. Ilerrick 

 (1924 b, pp. 404 and 400) at nests 

 in northern Ohio. Here, as is their 

 frequent custom, the eagles had con- 

 structed their nest about a mile from 

 the shore of Lake Erie, thus increas- 

 ing the availability of their favorite 

 food and at the same time reducing 

 the hours of search needed to supply 

 the dietary needs of themselves and 

 their growing young. In 1922, Dr. 

 Herrick found that 70 percent of the 

 food brought to the nest was fish. In 

 the following year fish constituted 



96 percent of the young eagles' food. 

 In explanation, Herrick comments: 



Among the fish, which were of various 

 sizes up to a possible weight of 3 or 4 

 pounds, and * * * often lacked the head, 

 we recognized the lake and common cat- 

 fish, sheepshead, sand and blue pike, carp 

 and perch— all common forms which can 

 be found almost any day, and in great 

 numbers after northerly storms have cast 

 them up on the beach. * * * We have 

 seen the eagles at Vermilion feeding regu- 

 larly on the dead fish which are swept on 

 the shores of the lake ; their preference 

 is undoubtedly for living prey, but like all 

 raptors they take readily to carrion when 

 nothing better is at hand and in this re- 

 spect perform a useful service. 



At another time Herrick ( 1938, 

 13. 51) stated that the fish "might 

 be taken off the beach, or cap- 

 tured by immersing at the surface 

 of the lake; in many instances these 

 fish were alive when they reached 

 the nest, although they may have 

 travelled from three to four miles 

 in the eagle's clutches." 



Mention has been made of the 

 bald eagle taking advantage of the 

 activities of other fish-eaters 

 (loons) to locate and attack schools 

 of fish in the water. The classical 

 incident of the opportunism of the 

 eagle is that associated with the 

 osprey, ^particularly along the At- 

 lantic coast in areas where both the 

 bald eagle and osprey are reason- 

 ably common. At such times the 

 eagle, usually at a height, will 

 watch and Avait for the osprey to 

 make a strike and rise from the 

 water with its prey. Then by per- 

 sistent and threatening swoops the 

 eagle either compels the osprey to 

 release its prey or, by striking from 

 beneath, will actually take the fish 

 from the talons of the osprey. If 



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