A report prepared by the Invasive Partnership for the Pacific Islands Forum Leaders Meeting, Palau July 2014 as requested by the Micronesian Chief Executives in Resolution 19-01
Call Number: [EL]
Physical Description: 16p. ; 29cm.
The world is facing a biodiversity crisis. Nowhere is that more apparent than on oceanic islands where invasive species are a major threat for island biodiversity. Rats are one of the most detrimental of these and have been the target of numerous eradication programmes; a well-established conservation tool for island systems.
The impacts of house mice (Mus musculus), one of four invasive rodent species in New Zealand, are only clearly revealed on islands and fenced sanctuaries without rats and other invasive predators which suppress mouse populations, influence their behaviour, and confound their impacts. When the sole invasive mammal on islands, mice can reach high densities and influence ecosystems in similar ways to rats.
Following the incursion of rats (Rattus rattus) on Taukihepa (Big South Cape Island; 93.9 km²) off southern New Zealand in 1963, and the subsequent extirpation of several endemic species, the New Zealand Wildlife Service realised that, contrary to general belief at the time, introduced predators do not reach a natural balance with native species and that a safe breeding habitat for an increasing number of at risk species was urgently needed.
Rat eradication is a highly effective tool for conserving biodiversity, but one that requires considerable planning eff ort, a high level of precision during implementation and carries no guarantee of success. Overall, rates of success are generally high but lower for tropical islands where most biodiversity is at risk. We completed a qualitative comparative review on four successful and four unsuccessful tropical rat eradication projects to better understand the factors influencing the success of tropical rat eradications and shed light on how the risk of future failures can be minimised.
On 6 January 2004. cyclone Heta devastated much of the South Pacific island nation of Niue. Extensive damage was done to forest, particularly of the north- western sector, with many trees up-rooted and others stripped of branches and foliage. This report details our findings from a survey of Niue's birds and rodents during 3-19 September 2004 and compares these with results from a similar survey in September 1994.
The study of dispersal processes of small mammals, and especially of rodents, has a wide range of applications and until recent years there were few publications discussing the
colonisation of 'oceanic' islands by small mammals (cf. Crowell, 1986; Diamond, 1987; Hanski, 1986;Heany, 1986; Lomolino, 1986).
In June/July 2002 an eradication programme to remove Pacific rats from Maninita Island in the Vava'u group of the Kingdom of Tonga was initiated. The techniques used were similar to those
used in successful rat eradications in New Zealand, in that Pestoff 20R pellets and a network of bait stations were used.
Conditions on the island were not what was expected, the forest having been adversely affected by cyclone Waka and subsequent defoliation by caterpillars, resulting in an open forest canopy. Rats were found to be present on the island in high numbers and were breeding.
The islands of Nu'utele and Nu'ulua have been identified as highly significant sites for conservation in Samoa. They hold large populations of species currently found nowhere else in the country' including threatened land-birds, seabirds and nesting
turtles. They also are the only offshore islands large enough and far enough offshore to be considered as refuges for several of the nation's species threatened on the larger islands by introduced mammalian pests. Such refuges have assumed greater