Determinants of Feeding Territory Size in the New Holland Honeyeater Phylidonyris novaehollandiae

Abstract

Territorial New Holland Honeyeaters were studied in an open-layered forest in north-eastern N.S.W. between 1981 and 1983. The birds aggressively defended productive inflorescences of both Banksia integrifolia and B. spinulosa. The size of feeding territories occupied by New Hollands (either alone or in pairs) decreased significantly as the density of inflorescences and the abundance of honeyeaters in the study area increased. Multivariate analyses suggested that changes in food density (inflorescence density) determine territory size while changes in intruder pressure (honeyeater numbers) have no significant effect except through the intervening variable of food density. Feeding territories may be held for only a few days but most last a number of weeks.