1968 THE DIURNAL BIRDS OF PREY 



better nesting places than the low mangroves. The number of eggs in a nest is 

 usually only two. 



The noble birds known as sea eagles, which include the largest 

 member of the whole family, differ from the preceding genus by the 

 absence of a naked space above the eye, and are further characterized by the lance- 

 olate feathers of the crown of the head, and by the wings reaching nearly or quite 

 to the end of the tail. The beak is long and powerful, straight for some distance 

 from the base, and then curving regularly downward in a deep hook. In the leg 

 the metatarsus is feathered for nearly half its length, and the naked portion reticu- 

 lated down to the toes, while the latter are scutellated above. The strong, curved 

 claws are grooved beneath, that of the first toe being the largest of all. There are 

 some eight species of sea eagles distributed over the whole world, with the excep- 

 tion of South America; and, as the habits of all are generally similar, it will be con- 

 venient to notice the species together, and then to consider their mode of life. It 

 may be mentioned that they are often confounded with the true eagles, from which 

 they may be distinguished at a glance by the naked lower half of the metatarsus 

 and the scutellation of its front surface. The sea eagles may be divided into three 

 groups, according to whether the tail in the adult is entirely white, black with a 

 white band at the end, or white with a terminal band of black. In the former group 

 the white-tailed or gray sea eagle (ffaliaetus albidlld) is noteworthy as being the 

 only species met with in the British Isles. In addition to the characteristic from 

 which it takes its name, it is distinguished by the brown abdomen, the brownish 

 wing coverts, and the ashy-brown hue of the head and neck, which are lighter than 

 the back. The female attains a length of thirty-eight inches, the male being about 

 four and one-half inches less. This species ranges across Europe and Northern 

 Asia from Ireland to Japan, and also occurs in Southern Greenland, while it extends 

 southward to Northwestern India. Its distribution includes the whole of Europe, 

 but it has now become extremely rare in the British Islands, although still breeding 

 in the Hebrides. The largest of all eagles are the giant or Steller's sea eagle 

 (H. pelagians], and the allied Corean sea eagle (H. bramcki], the former attaining 

 a length of forty-one inches. Steller's sea eagle, which is confined to the north- 

 eastern regions of the Old World, inhabiting Northeastern Siberia, North China, 

 Japan, and Kamchatka, is distinguished by its pure white wing coverts, thighs, and 

 upper and lower tail coverts, and is further characterized by its highly wedge-shaped 

 tail, which has fourteen feathers in place of the usual twelve. In young birds the 

 wing coverts and thighs are, however, brownish, although in this state the species 

 can be distinguished from the white-tailed sea eagle by the head and neck being of 

 the same dark hue as the back. The Corean species is a uniform slaty-black color, 

 without the white shoulder patches, thighs, and tail coverts. In correspondence 

 with their giant size, the cry of both these species is much louder and more pene- 

 trating than that of all the other eagles. It is remarkable that a leg bone, appar- 

 ently referable to Steller's sea eagle, has been obtained from the superficial deposits 

 of Walthamstow in Essex. The white-headed sea eagle, or bald eagle (H. leucoce- 

 phalus) , the national emblem of the United States, differs from the white-tailed 

 species, by having the whole of the head and neck pure white; the rest of the plum- 



