Order PELECANIFORMES 
No. 286. 
Family FREGATIDM. 
FREGATA ARIEL TUISTNYI. 
WESTERN LESSER FRIGATE BIRD. 
(Plate 230.)* 
Fregata ARIEL TUNNYi Mathews.. Austral Av. Rec., Vol. II., p. 121, 1914 ; Bedout Island, 
Mid-west Australia. 
Fregata ariel Tunny, Emu, Vol. I., p. 73, pi. ii., 1902 ; Hartert, Nov. Zool., Vol. XII., 
p. 207, 1905 ; Crossman, Emu, Vol. IX., p. 149, 1910. 
Tachypetes minor Walker, Ibis 1892, p. 259; Carter, Emu, Vol. III., p. 211, 1904. 
Fregata ariel tunnyi Mathews, Austral Av. Rec., Vol. II., p. 121, 1914. 
Distribution. Mid- and North-western Australia. 
Adult male. As in the preceding race but larger. Iris dark brown ; leg black ; bill blue 
from skin. Culmen 88-94 mm., wing 532-553, tail 365, middle toe 46. 
Adult female. Differs from the adult male in having the breast and sides of breast buffy- 
white ; a chestnut collar on the lower hind-neck ; lesser and median upper wing- 
coverts brown with whitish edges and blackish shaft-streaks, the long scapulars 
brown at the ends. Bill bluish horn ; iris brown ; eye-rim and gular-sac red ; 
feet fleshy-red. Total length 800 mm. ; culmen 92, wing 565, tail 335, tarsus 23. 
Immature. Undescribed. 
Nestling. Pure white down throughout save round eyes and fore-head, where it is rusty- 
red ; gullet naked ; patch of brown feathers on back. Iris black ; legs white. 
“ Bom naked like young Gannets ” (Walker). 
“ Older birds are covered with white down, with a saddle-shaped band of dark grey 
feathers across the back and scapular region ” (Walker). 
Nest. “ Of stalks of grass and Ipomcea, small twigs, etc. The average dimensions of each 
nest were about one foot in height by a little more in diameter ” (Walker). 
Eggs. “ A single egg, averaging 21^ X inches, pure white in colour, very thin- 
shelled, with only a very slight Hmy coating ” (Walker). “ One egg to each nest ” 
(Tunny). “Measurements 59.7-70.6 X 41-47.7 mm.” (Hartert). 
Breeding-season. April (Tunny) ; May (Walker). 
The only field-notes in regard to this form are from Mr. James Walker, who 
contributed to the Ibis 1892, p. 259, an account of the birds breeding on 
Adele Island, North-west Island : “ These fine birds had been noticed while we 
were wading over the flats, soaring high above all the sea-fowl, many of them, 
* The Plate is lettered Fregata ariel. 
288 
