species seen at Midway. But fewer birds participate and it is not so spectacular.
Its foods is fish; it dives from the air to catch them. One was examined which had a garfish in three folds in its gullet The part in the stomach was almost digested but the main part in the throat was perfectly fresh.
The young on the nest have a harsh cry if disturbed. The nests are found in nooks and hollows in the face of cliffs, often easily accessible. The breeding season is long, starting in April and I have seen eggs and newly hatched chicks in August One egg is laid, much streaked and spotted with red, ovoid, 2.5x1.5 inches.
| SULIDAE | Booby and Gahnet Family |
RED-FOOTED BOOBY
Sula sula rubripes Gould
Hawaiian name: A.
This small gannet is white; its head tinged with buff, upper wing-coverts and quills grayish brown not visible when the bird is sitting. Legs are red, bare skin of face and bill blue, with pink markings. Length 29 inches. There is a brown backed phase which has been considered immature but which I believe to be a mature phase. When banding in July and August 1938 on Howland, Enderbury and Jarvis Islands by taking careful counts I concluded that 98% of the birds were of the brown backed phase and on Palmyra 85%. In six visits to Moku Manu off the Oahu coast in 1937 to 1941 from May to November there were not more than 2% of the brown backed phase. The brown backed phase was present on Laysan and Lisiansky Islands in June 1891 but no estimate was made of the proportion of this phase to the white birds. Young birds in first plumage are brown, lighter underneath and some with a dark band across the breast. I believe they change quickly to the mature plumage. On October 3, 1940 I saw a red-footed booby of a uniformly beautiful gray color on Moku Manu. The egg, one in a clutch, is limy and bluish like the other gannets, 2.35x1.7 inches. The newly hatched chick has no covering when hatched. Its skin is black and exposure to the sun quickly kills it. However, a beautiful covering of pure white down soon protects it The old birds on the nests and later the large white chicks provide pretty sights on Moku Manu.
1. Hawaiian Hawk
2. Hawaiian Hawk
3. Hawaiian Hawk
4. Hawaiian Duck
5. Cackling Goose
6. Hawaiian Goose
(Three different phases of plumage.)
1. Laysan Island Rail
2. Hawaiian Coot
3. Hawaiian Rail
4. Spotted Hawaiian Rail
5. Hawaiian Gallinule
Red-footed booby (Sula sula rubripes) on nest on Moku Manu.
Photo by C. K. Wentworth.
Red-footed booby and chick on nest in Haole Koa, Ulupau Head, Oahu.
Photo by William V. Ward
This species differs little from the other two bobbies in flight and in feeding habits but its nesting is different. It dislikes the ground and never builds on the surface if it can find shrubbery to support its nest or trees to build in. However, when compelled to build on the ground it makes a neat nest of sticks and vines up about a foot high. It has a curious habit of sleeping with its head hanging to the full length of its long neck over the side of the nest and looks exactly as if dead.
BROWN BOOBY
Sula leucogaster plotus (Forster)
Other names: Common Booby; Hooded Booby; Brown-Vested Booby. Hawaiian name: A.
When I was on the island of Niihau in November 1939 I found that the natives there called all three boobies A, pronounced "ah." Andrews' Hawaiian Dictionary says: "Name of a large sea bird often caught by the natives; also called aaianuheakane, feathers white."
This well marked species is dark brown all over, except from breast backwards where it is pure white; bill pearl gray with bluish tinge; legs and feet pale yellow with a bluish tinge in the male. The female is larger than the male with bill stouter and longer. Average length 32 inches. It is larger than the red-footed species though there is little difference in length. The immature bird differs little from the immature of the red-footed. The downy chick is white, but naked when hatched; two eggs to a clutch, a dirty white limy shell covering with bluish underlay, 2.4x1.7 inches.
It nests in small companies on islands of the Hawaiian Chain, on Niihau, Moku Manu off Oahu and islands to the south. The largest colony I have seen was on Rose Atoll near Samoa. A young one taken from there to one of the Manua Islands near Samoa, seen in 1938, was tame and quite at home in a native village. Two banded birds travelled westward from Howland and Jarvis Islands, one about 3,800 miles nearly to New Guinea the other about 1,800 miles to Nauru. Another went a few hundred miles south as did two red-footed boobies.
Like the other boobies it flies high when fishing and dives straight down into the water, though sometimes obliquely when in full flight. Returning to its island it flies with heavy flapping flight dose to the surface of the water.
It nests on the ground using little material; on Niihau in 1939 they were on a ledge of a precipitous cliff. It is much persecuted by the frigate bird and this is probably the reason its communities are scattered.
BLUE-FACED BOOBY
Sula dactylatra personata Gould
Other names: Masked Booby; Masked Gannet. Hawaiian name: A.
This is the largest of our Hawaiian Boobies or gannets and averages about 33.75 inches in length,the female is over an inch longer than the male. Its plumage is almost pure white; wing quills, greater wing-coverts and tail feathers chocolate brown. Bill pale yellow, face blue-black; legs and feet yellowish brown; iris yellow. Immature birds are spotted with brown on the back when changing to adult plumage. Chicks are covered with white down. Two eggs are laid covered with a limy substance over pale bluish color, elongate ovate, they measure an average of 2.98x2 inches.
It has a wide distribution in the central and western Pacific. It breeds on islands of the Hawaiian Chain and on islands to the south. It is not known to nest in the main group unless perhaps on islands off Niihau. Caum saw a few nesting on Kaula in 1932.
Many banded on islands of the Equatorial group returned in succeeding years to the same island to breed; no banded birds of this species have so far been reported from a distance. '
Like the other boobies it flies high when watching for its favorite flying fish and low when returning to the nesting island. A large flock diving together into a close packed shoal of fish is a wonderful sight. When the young are in first plumage and changing to adult plumage they gather in flocks of several hundreds on the breeding island. The least disturbance day or night sets them off with loud raucous quacking. The female uses this loud
