ʻĀ – Red-footed Booby
|NatureServe Heritage Rank||G5 – Secure|
|North American Waterbird
|Not at risk|
The red-footed booby is the smallest of all booby species and they all have a pantropical distribution. There are three sub-species of the red-footed booby and one (E. S. subripes) of those three are resident species in Hawaii. The Hawaiian name, ʻā, is the same name shared with the other Hawaiian booby congeners–the Masked Booby and the Brown Booby–due to their similar body characteristics such as beak, feet, tail, and relative size.
Individuals have long pointed wings and a relatively long, wedge-shaped tail. They are normally all white. Adult male and females are overall white except for brownish black primary and secondary wing feathers; females are larger than males. The feet and legs are orange to red with a bluish bill save for the base of the lower mandible which is pinkish. The facial skin around the bill ranges from pink to red and blue.
They can forage alone or with mixed-species feeding-flocks. The foraging range is typically further from land than its congeners and can be seen plunge-diving from about 20 feet above into the water for flying fish, squid, sometimes mackerel scads, saury, and anchovies.
Breeding colonies range from ten to ten thousand pairs. Pairs tend to retain mates throughout several breeding seasons. Unlike their hawaiian congeners, they roost and build nests in shrubs or trees. Their breeding seeason is synchronous with the peak of egg-laying happening in February through April and most young have fledged by September, albeit they are able to nest year-round.
Both parents incubate the egg and brood and feed chick. Adults continue to feed their youngup to four months after fledging. Birds first breed at three to four years of age and the oldest known individual was 22 years old.
Most return to their natal colony to breed and usually nest in small colonies of tens of hundreds of pairs. As one of the only two ground-nesting booby species—the other is the Masked Booby (Sula dactylatra)—it is the only one that builds a nest as the construction is an important part of courtship. Nests are constructed from whatever is available including branches, seabird bones, and human debris.
Contrary to the Red-Footed Booby nesting, both the Masked Booby and Brown Booby typically lay two eggs per breeding season. The eggs hatch asynchronously, and the first chick to hatch usually pushes the other sibling out of the nest. Peak egg laying occurs between March and May and chicks fledge by September. Both parents incubate eggs and brood and feed chicks. Adults continue to feed young up to 37 weeks after fledging. Birds first breed at four to five years of age and the oldest known individual was 26 years old.
In Hawai‘i, the population is estimated at between 7,000 and 10,500 breeding pairs. The worldwide population is estimated at less than 300,000 breeding pairs, with the majority residing in the eastern Pacific. Hawai’i’s State Wildlife Action Plan October 1, 2015 (Last Updated October 2005)
‘Ā (red-footed booby) breed on small islands or islets, both on low-lying coralline sand islands and high volcanic islands. Nest in bushes or trees, including beach magnolia (Scaevola sericea) and beach heliotrope (Tournefortia argentea). Will occasionally nest on deserted man-made structures, on bare ground, or on low piles of vegetation. Builds a nest of twigs, grass, and other vegetation. Marine: Pelagic.
‘Ā (red-footed booby) breed throughout the NWHI and at a limited number of sites on MHI including Kīlauea Point National Wildlife Refuge on Kaua‘i, the cliffs of Ulupa‘u Head at the Kāne‘ohe Bay Marine Corps Base on O‘ahu, and on offshore islets including Moku Manu and Lehua. Little is known about the movements of the ‘ā (red-footed booby) outside nesting season, although in Hawai‘i they disperse eastward and move between islands.
ʻĀ are revered through profound kinship in meaningful practices of traditional Hawaiian lifestyles. Many of those understandings are being re-awakened through the community, the Office of Hawaiian Affairs, and the Kiamanu Project.
1. nvi. Fiery, burning; fire; to burn, blaze. Fig., to glitter or sparkle, as a gem; to burn, as with jealousy or anger. ʻĀ akaaka, to shine brightly, as stars. ʻĀ ke kaimana, the diamond sparkles. hoʻā To set on fire, burn, ignite; to light, as a lamp. Fig., to incite, arouse. Ua hoʻā ʻia kona inaina, his anger was aroused. Hoʻā imu, to light an oven; one who lights an oven. (PPN kakaha, PNP kaa.)
2. nvi. Aa lava, or lava rock, as distinguished from smooth unbroken pāhoehoe lava (formerly preceded by ke); to flow, as aa lava.
3. Same as ʻaʻa 1, to dare. ʻAʻole ʻoia i ʻā e noho, he did not dare to stay.
4. n. Red-footed booby bird (Sula sula rubripes), brown booby (Sula leucogaster plotus), masked or blue-faced booby (Sula dactylatra personata); all indigenous and also breeding elsewhere. Also ʻaʻa. Legendary birds believed to have taken the shape of this bird are ʻā ʻaia, ʻā-ʻai-ʻanuhe-a-Kāne and ʻā-ʻaia-nui-nū-keu; ʻā by some were considered ʻaumākua. See also Kep. 33.