Partitioning of nectar resources by New Zealand honeyeaters

Abstract

Ideas of community structure and game theory are used to predict the type of flowers that the three species of New Zealand honeyeaters should use. Flowers are ranked on a preference scale of 1–5 according to likely net energy returns to a foraging bird. Their relative use is related to the interspecific status of the honeyeaters. The more dominant tui Prosthemadera novaeseelandiae fed predominantly on the highest preference flowers (Types 1 and 2); the next most dominant bellbird Anthornis melanura fed on flowers of intermediate preference (Types 2 and 3). The subordinate stitchbird Notiomystis cincta fed on low preference flowers (Type 4) but also on the highest preference (Type 1) flowers. Stitchbirds avoided contact with the similarly ranked bellbird as predicted by game theory. Division of trees of differing quality and even of parts of a tree with differing flower abundance also related to status. The implication of these results on conservation of the rare stitchbird is discussed.

Keywords:

• resource partitioning
• nectar
• honeyeater guild
• status
• Prosthemadera novaeseelandiae
• Anthornis melanura
• Notiomystis cincta