232 MANUAL OF PHILIPPINE BIRDS. 
Genus HALLHETUS Savigny, 1809. 
Bill stout, culmen straight atypase, then greatly curved, with a long 
overhanging hook, edge sinuate> tail rounded, its feathers wide and 
pointed ; tarsus heavy, feathered for a short distance in front; a row of 
large transverse plates in front, a row of large hexagonal scales behind, 
sides covered with small hexagonal scales. 
190. HALIZZETUS LEUCOGASTER (Gmelin). 
WHITE-BREASTED SEA EAGLE, 
Falco leucogaster GMELIN, Syst. Nat. (1788), 1, pt. 1, 257. 
Haliaetus leucogaster SHARPE, Cat. Birds Brit. Mus. (1874), 1, 307. 
Haliaétus leucogaster SHARPE, Hand-List (1899), 1, 267; Oates, Cat. Birds’ 
Eggs (1902), 2, 279; McGrecor and Worcester, Hand-List (1906), 43. 
Ma-na-ol’, Ticao, Manila. 
Bantayan (McGregor); Batan (McGregor); Basilan (Bourns & Worcester, 
McGregor) ; Bohol (McGregor) ; Bongao (Hverett) ; Calamianes (Bourns & Wor- 
cester); Calayan (McGregor); Camiguin N. (McGregor); Cebu (McGregor) ; 
East Bolod (Mearns) ; Fuga (Whitehead) ; Luzon (Bourns & Worcester) ; Masbate 
(Bourns & Worcester, McGregor) ; Mindanao (Steere Exp.) ; Mindoro (Bourns & 
Worcester, McGregor, Porter) ; Palawan (Whitehead, Platen, Bourns & Worcester, 
White) ; Romblon (Bourns & Worcester) ; Samar (Steere Exp., Bourns & Worces- 
ter, Whitehead) ; Semirara (McGregor & Worcester) ; Sibuyan (Bourns & Worces- 
ter, McGregor) ; Siquijor (Bourns & Worcester); Sulu (Bourns & Worcester) ; 
Tablas (Bourns & Worcester, Celestino) ; Tawi Tawi (Bourns & Worcester) ; Ticao 
(McGregor) ; Verde (McGregor) ; Y’Ami (McGregor). Indian Peninsula; Indo- 
Chinese Provinces; Malay Peninsula to Australia and Oceania. 
Adult.—Entire head, neck, and lower parts white, many of the feathers 
with blackish shafts; tail blackish, its terminal third white; primaries 
blackish with white bases; axillars and wing-lining white; remainder of 
wings and upper parts bluish slate-gray, with a slight mixture of brown. 
Male from Ticao: Iris dark; bill at base and cere horn-blue; bill at tip 
and nails black; legs and toes white. Length, 685; wing, 550; tail, 230; 
culmen from base, 52; tarsus, 91. The female is said to be slightly larger. 
Young.—Head, chin, and throat buffy or pale yellowish white, more 
or less streaked with light brown; general color brown, darker above, 
many of the feathers with lighter brown or whitish shaft-lines which 
widen at the tips; primaries black with whitish bases; end of tail brown, 
basal two-thirds white mottled with brown. 
The white-breasted sea eagle is widely distributed but nowhere in the 
Philippines is it abundant. In adult plumage it is easily identified by 
its white under parts. Its nest consists of a mass of sticks and is usually 
supported by the branches of some large tree. Islets on which there 
are but a few trees are in particular favor with this species. The 
eggs are usually spheroidal and white with a few faint markings of 
reddish brown. 
