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Providing evidence to improve practice

Individual study: Rat Rattus control at nests of the endangered kakapo Strigops habroptilus on Codfish Island, New Zealand

Published source details

Jansen W.P. (2005) Rat Rattus control at nests of the endangered kakapo Strigops habroptilus on Codfish Island, New Zealand. Conservation Evidence, 2, 1-2


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Control mammalian predators on islands for parrots Bird Conservation

A small before-and-after study on Codfish Island (1,500 ha), New Zealand (Jansen 2005) found that none of six kakapo Strigops habroptilus nests were lost to rats Rattus spp. in 1997, when there was intensive trapping and poisoning of rats close to nests (in conjunction with remotely operated detonators to scare rats, see ‘Guard nests to prevent predation’). In contrast, there were potentially unsustainable predation rates before 1997.  The study does not adequately describe the impact of predator control on the species – the translocations and subsequent population stabilisation would only have been possible with prior control.

 

Guard nests to increase nest success Bird Conservation

A small before-and-after study in 1997 on Codfish Island (1,500 ha), New Zealand (Jansen 2005) found that remotely operated detonators successfully scared rats Rattus spp. from kakapo Strigops habroptilus nests on two occasions. In conjunction with intensive trapping and poisoning of rats on a grid system around six nests (see ‘Control mammalian predators on islands’), this ensured that no nests were lost to rats in 1997, compared with potentially unsustainable predation in the years preceding 1997. No adverse effects on kakapos were found.