Sterna bergii Saunders, Cat. Birds Brit. Mus. (1896), 25, 89
(part); Sharpe, Hand-List (1899), 1, 136 (part).
Sterna bergii boreotis Bangs, Bull. Mus. Comp. Zool. (1901),
36, 256.
Sterna boreotis McGregor and Worcester, Hand-List (1906), 20.
Ga-bi-o'-ta, general name for gulls and terns.
Agutaya (McGregor); Balabac (Steere); Bantayan (McGregor); Bohol
(Everett, McGregor); Calamianes (Bourns & Worcester); Caluya
(Porter); Cebu (Bourns & Worcester, McGregor); Cuyo (McGregor);
Guimaras (Bourns & Worcester); Leyte (Everett); Luzon (Bourns &
Worcester); Masbate (Bourns & Worcester); Mindanao (Murray, Koch &
Schadenberg, Steere Exp., Bourns & Worcester); Mindoro (Porter);
Negros (Bourns & Worcester, Keay); Palawan (Whitehead, Platen,
Bourns & Worcester, White); Panay (Bourns & Worcester); Pata
(Mearns); Romblon (Bourns & Worcester, McGregor); Samar (Bourns
& Worcester); Sibuyan (Bourns & Worcester); Siquijor (Bourns &
Worcester, Celestino); Sulu (Bourns & Worcester); Tablas (Bourns &
Worcester); Tawi Tawi (Bourns & Worcester). Liu Kiu Islands and
Northern China Sea.
"Adult male in full breeding plumage (type).--Forehead, cheeks,
lores, ear-coverts, neck all round, and whole under parts, including
lining of wing and bend of wing, pure white; crown and long occipital
crest glossy black; mantle, wings, rump, upper tail-coverts, and
upper surface of middle rectrices dark smoke-gray, darkest on wings
and middle of back, where the color is almost mouse-gray; primary
quills white; first primary with outer web, a band along quill on
inner web and tip blackish, with a silvery suffusion which is most
marked toward center of feather; broad outer margin of inner web,
below the black tip, white; second primary similar but black tip
deeper in color and extending a short distance down outer margin of
inner web, thus inclosing the white of inner web for a short distance;
third, fourth, and fifth primaries like second, but black tip gradually
growing deeper in color; outer rectrices above pale smoke-gray at tips
and along shafts, pale grayish white toward base; second and third
rectrices darker on the outer webs and at tip and whitish toward base
of inner webs. Bill in dried specimen, dull yellow clouded with olive
toward base; feet and tarsi blackish. Wing, 344; tail, 178; tarsus,
28; culmen, 62." (Bangs.)
"Very common throughout the group, especially abundant about the
native fish-pens." (Bourns and Worcester MS.)
This is much the largest tern found in the Philippines. Rather local
in its distribution but usually found not far from fish-corrals or
where schools of small fishes appear near the surface of the water.
Philippine records of this species are usually recorded under Sterna
bergii, but the specimens probably belong to the variety S. bergii
boreotis. The question can not be cleared up at present.