Birds of Hawaii. George C. Munro
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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 quack when disturbed on the nest but the adult male has only a squeaking or hissing sound; the pair stay together by the nest a great part of the time. Flying fish are plentiful near the islands and the birds are almost always replete. The frigate birds despoil them of their catch, though they succeed in retaining sufficient to feed their young. One observer is positive that it always gives up a flying fish to the frigate, retains a squid for its young and a flying fish for itself.
Immature noddy tern (Anous stolidus pileatus Scopoli) on Rabbit Island, Oahu.
Photo by William V. Ward.
Red-footed boobies on nests, Moku Manu. Large downy chick sitting up in middle. Sooty tern and other birds in the air.
Photo by C. K. Wentworth.
They nest in scattered companies laying their two eggs on the bare ground. The young bird in taking its food from the parent thrusts its head right down the old bird's throat.
| FREGATIDAE | Frigate Bird Family |
FRIGATE BIRD
| Fregata minor palmerstoni (Gmelin) | Plate 7, Fig. 7 |
Other name: Man-o'-War Hawk. Hawaiian name: Iwa (a thief).
Hawaiian tern or white-capped noddy (Atwus minutus melanogenys) on Midway Island.
Photo by courtesy of the Bishop Museum.
The female is larger than the male, their average length being about 37.5 inches. Their wing spread is over 7 feet. Bills are strongly hooked at the tip, and their feet much atrophied so as to be almost useless to them. The male is black above with a metallic gloss of green and purple on the feathers, long lance shaped feathers on the back; blackish brown below; wings and deeply forked tail black; gular pouch reddish yellow, capable of being blown up into a scarlet balloon under its beak as a mating attraction. The female is blackish brown with little gloss, breast white; scarlet round the eyes, gular pouch and greater part of lower mandible, rest of bill gray; legs pinkish white. The young have head and neck brick red changing to white, probably before they take wing, upper parts brown and lower white. Chicks are covered with white down. The egg is white, oval, 2.5x1.1 inches. When the chick is well grown a second egg is sometimes laid, and a large chick and an egg or a large chick and a small one may be seen on some nests. A curious sight is to come on a rookery with males sitting on the nests, a number of them with their red neck bladders partly blown up; once I counted 8 close together.
Red-tailed tropic bird (Phæthon rubricauda rothschildi Matthews) on Midway Island.
Photo by courtesy of the Bishop Museum.
This bird cannot stand, walk or probably even swim. But in the daytime, at least, it can live almost indefinitely in the air. The night air currents may not be so favorable to it in flight thus it generally returns to its roosting place in the evening, where it sits on some slightly elevated object. It can catch fish from the surface of the water without alighting, rob other birds in the air, pick up a small object from the ground if it has fairway to drop down, poise itself over it and rise unimpeded. Only once did I see one settle on the water and to my surprise it rose from the surface without difficulty. It is almost helpless to take wing from a perfectly level land surface. A slight elevation permits it to spread its wings and utilize the warm upcurrent of air, when a few flaps takes it off. They swarm over every nesting island; floating high in the heavens, mere specks in the distance and soaring in the air at every level, and numbers sitting on their nests on top of the shrubbery. Where there are no plants large enough to support their nests they build up from the ground, robbing other nests for material if left unguarded.