Food Caching in the Tropical Frugivore, Macgregor's Bowerbird (Amblyornis macgregoriae)

Males of MacGregor's Bowerbird (Amblyornis macgregoriae) cache fruit. In a study population in eastern Papua New Guinea we found 437 cache sites at 39 bowers. Adult males stored an average total of 17.6 fruits (range 0-82) at 13.6 sites (range 0-55), significantly more than immature males. All sites were located in vegetation above ground within 13 m horizontal and 9 m vertical distance from the males' bowers. For 3 males studied intensively, the rate of replacement of caches averaged 0.13 replacements· site⁻¹· day⁻¹, with no significant differences among males. Caching occurred only during the seasonal periods of bower attendance and breeding activity. Females did not store fruit and did not take fruit stored by males. We suggest that by extending the time males can remain at their bowers, caching may increase interaction time with females and decrease rates of bower marauding by rival males. There was no evidence that cached fruits served as bower decorations.