Abstract
In the Top End of the Northern Territory of Australia Red-tailed Black Cockatoos have been known to nest in hollows in Eucalyptus forests. However no detailed description of nest and food requirements exists. This study determines suitable nesting and foraging habitat, describes attributes of nesting trees, the density, availability and spatial distribution of these trees, daily feeding patterns, seed availability and movement by C. b. macrorhynchus during the breeding season. Based on the results I aimed to assess the feasibility of using the recently developed harvesting management program for C. b. macrorhynchus on privately owned land as a means to encourage protection of nesting habitat.Results show that the birds nest in the widespread open Eucalyptus miniata / E. tetrodonta forests and E. papuana / E. polycarpa woodlands. Up to 81 % of trees with a DBH > 30 cm contain hollows large enough for a Red-tailed Black Cockatoo to enter (hollow entrance >15 cm). Other important nest tree features are inside hollow depth (between 40 and 130 cm) and the entrance height above ground (> 9m). Trees with hollows large enough for Cockatoos to enter occur in low densities of 0.5 − 1 tree per hectare and are spatially distributed in a uniform fashion (P = 0.0087). Only 5.8 % of such trees are suitable for nesting.
Foraging occurs in Eucalyptus low open - woodlands, woodlands and in coastal vegetation. Foraging sites are close to nest sites and fires are an important feature of the sites that tend to be recently burnt, providing easy access to grass seeds, the major component of the bird's diet. During the whole breeding season (March – September) 85 % of the birds feed in the early morning and late afternoon, using sites until seed availability significantly decreases (P
| Date of Award | Nov 2000 |
|---|---|
| Original language | English |
| Supervisor | Peter Whitehead (Supervisor) & Richard Noske (Supervisor) |