Small birds, Lerp-feeding and the problem of Honeyeaters

Abstract

Honeyeaters often defend rich sources of carbohydrates such as nectar and lerps (exudates of psyllids). Lerps are also a major food item of pardalotes, and consequently these birds are attacked frequently by honeyeaters, especially in winter and spring. Up to 5% of daylight time and 9% of energy expended may be wasted by pardalotes escaping from honeyeaters. This susceptibility to attack may have been influential in the development of hole-nesting by pardalotes and may have deterred other small foliage-gleaning birds from eating lerps.