Nest site selection and breeding success in large Australian honeyeaters: Are there benefits from being different?

Red Wattlebird Anthochaera carunculata (n = 97) and Noisy Friarbird Philemo n corniculatus (n = 229) nests were monitored over eight breeding seasons i n eucalypt woodland in northern New South Wales. Red Wattlebirds nested in Eucalyptus viminalis and E. bridgesiana more frequently than expected from their relative abundance at the site. Noisy Friarbirds avoided stringybarks (E. caliginosa) but selected other eucalypts disproportionately. Nest succ ess was similar in the two species (33% in Red Wattlebirds and 38% in Noisy Friarbirds), despite Friarbird nests being placed further horizontally fro m the base of the nest tree and being more conspicuous. The similar success may be because Noisy Friarbird nests are more inaccessible to mammalian pr edators and Red Wattlebird nests are less conspicuous to avian predators. I n addition, Noisy Friarbirds tend to be more aggressive to avian predators than Red Wattlebirds, which may allow them to benefit from nests that have a good view of their surroundings. Neither species showed a relationship be tween nest success and nest height, horizontal distance from the base of th e tree, nest tree height and trunk diameter or nest conspicuousness. Noisy Friarbird nests in E. blakelyi, although chosen most frequently, were less successful than those in other tree species and nests around mean height we re less often successful than those higher or lower. The difference in nest locations between the species and diversity of nest sites chosen within ea ch species could reduce the chance of a nest predator developing search ima ges for specific nest locations. The suggestion that Noisy Friarbird nests in less common locations are more likely to be successful supports this hyp othesis. Nests at the edge of the habitat patch and near tracks used by hum ans did not differ in their success rate from nests in the centre of the pa tch or away from tracks.