Energetic patterns and lifestyle in the meliphagidae1

Abstract

Standard metabolic rates (SMR) of 10 species of Australian honeyeater birds (Passeriformes: Meliphagidae), inhabiting coastal heath- land and woodland settings north of Sydney, N.S.W., were measured using indirect calorimetry. These birds varied in body mass from 10-120 g, enabling allometric analyses, and comparisons with values expected for other passerine birds. Across this size range SMR was uniformly depressed to about 66% of that expected for passerines. The equation describing the allometric relationship between SMR during the active phase (in ml 0,/g. h) and body mass (mass in g) for these 10 honey- eater species was SMR=6.68 M,:i. I conclude that this reduction in SMR represents a functional response to selective pressures related to nectarivory as a lifestyle. © 1985 Crown copyright.