Kauai O-O-AA Birds Facts – Honeyeaters
There is no very recent estimate of the population of the 0-0-aa (Moho braccatus), a 19-21.5 cm (7.5-8.5 in) Hawaiian honeyeater, though one or two were seen at the end of the 1970s and a handful may remain on Kauai Island.
A population of ‘less than 10’ was suggested in 1985. Honeyeaters generally have been a very successful family, with 167 species (450 sub-species) in 38 genera, concentrated in Australia, New Guinea, New Zealand, the south-west Pacific, Indonesia and South Africa.
History of Honeyeaters
There were once at least five species in Hawaii, but the kioea and one Moho became extinct in about 1840. Another species of Moho has not been seen since the beginning of this century and is presumed extinct.
Moho braccatus is thought to survive in the more remote and inaccessible forests where its diet is predominantly insectivorous. It climbs the moss-covered tree trunks in the manner of a woodpecker, aided by its stiff tail, looking for insects and spiders, beetles and small snails. They have also been seen to take laplapa berries.
Kauai O-O-AA Diet and Habitat
All honeyeaters have a long, protrusible tongue with a brush-like tip that can be used to extract nectar, and in some countries, they are important pollinators of flowers— in fact, some species have coevolved with certain species of plant. The tip of the tongue is deeply cleft into four parts which are delicately frayed on the edges, forming the so-called brush. The tongue is extended into the nectar or other liquid about 10 times a second and the liquid drawn up by capillary action. When the tongue is withdrawn the mouth is closed and projections on the roof of the beak appear to compress the liquid from the brush along the two grooves at the base of the tongue leading to the throat. Despite this common characteristic honeyeaters are very variable in size and habits.
Some Causes of decline of the Kauai O-O-AA
It is not clear what has caused the decline of the Kauai 0-0-aa. Between 1968 and 1973 the population was estimated at 22—36. For many years it was thought to be extinct, but was rediscovered in 1960 in the depths of the Alakai Swamp region, in the undisturbed native ohia forest between elevations of 1,143 m (3,750 ft) and 1,295 m (4,250 ft).
There the birds preferred the thick forest habitat and more were seen or heard in high canyons than on the forested ridges. A few nests with two young were subsequently found high up
in tree cavities.
Hunting for honeyeater plumes was once extensive among Polynesians, who used such feathers to adorn ceremonial garments, but the tribesmen are not likely to have been significantly responsible for the decline of the largely inaccessible Moho braccatus population as the species has relatively inconspicuous plumage. Also, birds were generally caught in the moulting season, plucked and then set free.
Shrinking forests and associated disturbance are likely to have been more influential factors. And even in the most remote areas the forests are increasingly infiltrated by exotic plants that displace the indigenous nectar sources. introduced birds compete for food and territory and the increasingly common black rat can climb trees to take eggs and chicks.
There is a possibility that a second Moho – bishopi (Bishop’s 00) survives in the dense Hawaiian rainforest. It was rediscovered in 1981 after going unrecorded since 1904. An American ornithologist called Mountain spring spotted it on Maui, on the windward slope of the eight-mile-wide crater Haleakala, on the powdery floor of which the Apollo astronauts had trained for their missions.