Rodents

Rodents are a key pest to agricultural and rural island communities of the South Pacific, but there is limited information of their impact on the crops and livelihoods of small-scale farmers. The rodent pest community is known, but the type and scales of damage to different crops on different islands are unknown. Knowledge about rodent pest management in other geographical regions may not be directly transferable to the Pacific region. Many studies on islands have largely focussed on the eradication of rodents from uninhabited islands for conservation benefits.

There are five toxicants (brodifacoum, bromadialone, coumatetralyl, diphacinone, and flocoumafen) registered for rodent control in New Zealand. They are all anticoagulants and are available in water-resistant bait formulations (i.e. wax coating, wax block, or egg). Several new rodenticide products, which are currently in the process of being developed or registered, including a new anticoagulant difethialone, have also been identified.

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

Invasive species compete with endemic species and if successful can displace native species in the host region (Cororaton et al., 2009).

The spread of invasive non-native species presents one of the greatest threats to biodiversity globally: invasive species are the primary driver of biodiversity loss on islands and the second largest everywhere else (CBD ; Millennium Ecosystem Assessment, 2005). Many of the UK’s island ecosystems have been damaged by the arrival and establishment of invasive non-native species. Introduced predators have caused particularly catastrophic damage to many species of waders and seabirds, undoubtedly causing numerous extirpations as well as contributing to ongoing declines(Stanbury et al. 2017).