Foraging Behaviour and Resource Selection of the Regent Honeyeater Xanthomyza phrygia in Northern New South Wales

Abstract

Foraging observations of the endangered Regent Honeyeater show that it has a more generalised diet, and is less nectar-dependent, than previously suggested. On average, birds spent 60% of their foraging time feeding on nectar from the flowers of Mugga Ironbark Eucalyptus sideroxylon, other eucalypts and three mistletoe species. Gleaning for lerp and hawking for insects comprised 35% and 5% of their foraging time, respectively. When nectar was scarce, however, Regent Honeyeaters spent up to 90% of their foraging time feeding on lerp, honeydew and insects. A variety of different foods were collected from a broad range of tree and mistletoe species. Mugga Ironbarks were the most important foraging plants, with 31 other species also used for food. Regent Honeyeaters, typically, feed in the tallest trees in their environment; hence, adequate protection should be given to mature trees. Regent Honeyeaters showed significant variation in their foraging patterns between years, and at different times of the day. Breeding birds spent a greater proportion of their foraging time collecting nectar in 1996 than 1995, due to a higher eucalypt nectar availability in 1996. In both years nectar-feeding was highest in the morning and late afternoon and lowest in the middle of the day, when insect and lerp consumption peaked. The degree of flexibility in the foraging repertoire of the Regent Honeyeater is not unusual among Australian honeyeaters, although it indicates that different types of food and a broad range of plants, particularly mature eucalypts, have to be protected and properly managed to save this declining woodland bird.