160 SHORT NOTE What triggers nesting of kakapo (Strigops habroptilus)? GRANT A. HARPER triggers of nesting on Little Barrier Island in northern Zoology Department, Otago University, P.O. New Zealand, and present a generalized model for the Box 56, Dunedin, New Zealand. initiation of nesting in kakapo. Phenological data on the temporal distribution and GRAEME P. ELLIOTT abundance of rimu fruit on Codfish Island have been Research, Development & Improvement Division, Department of Conservation, collected since 1996 by counting the proportion of fruiting Private Bag 5, Nelson, New Zealand. tips on four marked branches of the same 10 trees each year. Meteorological data were obtained from weather DARYL K. EASON stations on Stewart Island (adjacent to Codfish Island) and Research, Development & Improvement Leigh (near Little Barrier Island). Nesting was detected by Division, Department of Conservation, monitoring the behaviour of radio-tagged female kakapo Private Bag 5, Nelson, New Zealand. as described by Eason et al. (2006). RON J. MOORHOUSE On Codfish Island, nesting has only occurred when Research, Development & Improvement >10% of rimu branch tips bore fruit in October (Fig. 1). Division, Department of Conservation, As it ripens, rimu fruit differentiates into a black seed and Private Bag 5, Nelson, New Zealand. red, fleshy aril but in October is green and undifferentiated
[email protected] (Salmon 1991). Since female kakapo begin feeding on green rimu fruit in late October and early November, it is likely that some characteristic of this triggers them to Kakapo (Strigops habroptilus) are unusual in that, mate and nest in January and February. Although higher although some males may engage in courtship activity in energy, green rimu fruits are lower in protein and fat every year, nesting occurs only at three - four year than the nuts and food pellets that have been provided intervals (Powlesland et al.