Individual study: Supplementary feeding to support nesting female kakapo Strigops habroptilus on Codfish Island, Southland, New Zealand
Elliott G.P., Merton D.V. & Jansen W.P. (2001) Intensive management of a critically endangered species: the kakapo. Biological Conservation, 99, 121-133
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Provide supplementary food for parrots to increase reproductive success
A 2001 review of data from Little Barrier Island, North Island, New Zealand, between 1990 an 1999 (Elliott et al. 2001), using largely the same data as Clout & Merton 1998, found that female kakapos Strigopus habroptilus provided with supplementary food (nuts, apples and sweet potatoes provided at feeding stations year-round) bred significantly more frequently than females that did not take supplementary food (11 breeding attempts in 35 ‘bird years’ for fed birds vs. one breeding attempt in 82 ‘bird years’ for unfed birds). The authors note that the mechanism behind the relationship and that the response was extremely variable across other islands. A small analysis in the same study found that four fed females did not produce larger clutches than two unfed females (average of 2 eggs/clutch for both fed and unfed females). Neither of the unfed females raised young (and only one egg hatched), whereas a total of three chicks fledged from fed nests, but samples were too small to determine whether this difference was significant. Failure of both unfed nests was thought to be due to females spending large amounts of time away from the nest during incubation.
Artificially incubate and hand-rear parrots in captivity
A 2001 review of data from the kakapo Strigops habroptilus management programme in New Zealand (Elliott et al. 2001) found that 22 chicks were removed from nests between 1992 and 1999, with nine surviving (41%) and being released into the wild. These nine represent 60% of the 15 birds fledged between 1990 and 2001. However, the authors note that eggs artificially incubated from an age of less than ten days old had low success rates. None of the birds raised had reached breeding age by the time of the review, so their breeding behaviour and success was unknown.