GAME BIRDS 



The relationship of the golden 

 eagle to upland game birds has long 

 been a matter of debate. In Eng- 

 land and on the continent, the black 

 grouse {Lyrwrus tetrix) and other 

 gallinaceous birds have been re- 

 ported preyed on by the eagle. 

 During the 19th century this one 

 factor Avas considered responsible 

 for the serious depletion of game- 

 bird populations in some European 

 areas (Oberholser 1906). 



In this country, little regard lias 

 been given to the possible effect of 

 this large bird on various species of 

 grouse until recent years. Among 

 earlier workers, Ridgway (1877) 

 reported a pair of golden eagles 

 giving chase to and capturing a sage 

 lien. In this instance the eagles 

 pursued the grouse on the wing 

 until it dropped to the ground from 

 exhaustion, where it was picked up 

 by the foremost of the large birds. 



Sharp-tailed G r on s e. — That 

 golden eagles at times may levy a 

 substantial toll upon sharp-tailed 

 grouse first gained emphasis when 

 Cameron (1905) reported that one 

 eagle nest under observation in 

 Montana always had the remains of 

 grouse in it when visited. He also 

 noted that when the yoving eagles 

 were nearly grown they were fed 

 almost exclusively on this game 

 bird. Later, C a m e r o n (1908) 

 pointed out that eagles nesting in 

 territory wliere grouse were not 

 plentiful fed their young largely on 

 jackrabbits and prairie dogs. 



Tlio etrectiveness of cover in })ro- 

 tectiug prey species from attack by 

 the gohlen eagle was recognized by 

 Barrows ( 1912 ) . He tells of three 



instances in which golden eagles 

 were caught alive after becoming 

 entangled in bushes and vines where 

 evidently, they had plunged after 

 some quarry they had failed to cap- 

 ture. A similar case was recorded 

 by Prudy (1898) near Northville, 

 Mich., in which a golden eagle was 

 so intent on its pursuit of a covey 

 of bobwhites that it entangled itself 

 in a thicket of raspberry bushes. 



PheoJiOnt. — The golden eagle's in- 

 fluence on pheasant populations 

 varies with local conditions. Illus- 

 trative of this is the somewhat ex- 

 treme situation that existed at a 

 game farm near Dawson, N. Dak., 

 late in the winters of 1939^0 and 

 1940-41. The North Dakota Game 

 Department had sanctioned the kill- 

 ing of eagles on this area of pheas- 

 ant concentration during the 2 

 winters. This decision was based 

 on investigations which disclosed 

 definite predation on and disturb- 

 ance of the pheasant po])uhition by 

 eagles. The game farm had an es- 

 timated population of 15,000 pheas- 

 ants, and cover was not dense over 

 most of the area. 



The depredations by the eagles 

 were described as follows by E. M. 

 Lee, chief game warden : 



As soon as the eagles had finished their 

 meal they would perch in tall Cottonwood 

 trees which are growing in scattered 

 places over the farm. Game birds noting 

 tlie perching eagles would remain in 

 liiding for hours. After one pair of eagles 

 li.id been Ivilled everything was quiet for 

 I wo or three days, and then another pair 

 would invade the ranch. At times a 

 week would intervene before the succes- 

 sors came. * * * i have personally ob- 

 served eagles at two different times take 

 plieasants, and the pheasants taken were 

 both feeding. Apparently they do not see 



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