Ecology and Conservation of The Ouvea Parakeet, Eunymphicus cornutus uvaeensis (Loyalty Islands, New Caledonia)

Abstract

The Ouvea Parakeet Eunymphicus cornutus uvaeensis, is an endangered bird endemic to Ouvea, Loyalty Islands, in the New Caledonian archipelago. Its population is estimated to be 300-600 birds, mainly in patches of forest in the north, with few parakeets in the centre and the south of the island. Its main habitat is high forest mixed with Melanesian fields. Within habitat distribution is very patchy, with an apparent site attachment during the breeding season. Radio tracking revealed that the home range of juveniles was small, and no dispersal was observed. The diet of the parakeets comprises the seeds and fruits of more than 23 plant species, including Ficus spp., Carica papaya and Rhamnella vitiensis. These plants have a long and asynchronous fruiting season, leading to an apparent abundance of food during the year. The number of breeding pairs was correlated with the density of potential nest sites in the three study areas, suggesting a nest site limitation. The length of the breeding season (August until January) allows the occurrence of double clutches. The parakeets nest in secondary cavities of only five species of trees (90% n Syzygium pseudopinnatum and Mimusops elengii). The clutch size is 2.9 eggs (range 2-4), of which on average 2.6 chicks hatch, 1.65 fledge, but only 0.75 per breeding pair is still alive 30 days after fledging. The main causes of loss are starvation of the third sibling due to hatching asynchrony, human harvest, and raptor predation after fledging. Ouvea is free of Ship Rat Rattus rattus and Norway Rat R. norvegicus. Kiore R. exulans, the rat present, is responsible for only a few predations at nests. The main predators are the Brown Goshawk Accipiter fasciatus, and humans that capture chicks to sell them as pets. 15-30 chicks are still captured every year and sold outside Ouvea. A population viability analysis of the Ouvea Parakeet shows that, with the current carrying capacity, this harvest is not sustainable and would eventually lead to extinction. Long-term survival would be best secured by establishing another population of 4-500 birds in the south of Ouvea, by increasing carrying capacity through habitat protection, nest site provision and restoration, decreasing the harvest and preventing the introduction of Ship Rat in Ouvea.