Invasive alien species are recognised as one of the leading threats to biodiversity and also impose enormous costs on agriculture, forestry, fisheries, and other human enterprises, as well as on human health. Rapidly accelerating human

In 2001, the Government of Samoa released the National Biodiversity Strategy and Action Plan (NBSAP) for the conservation and sustainable development of the country's biological resources. The NBSAP identifies invasive alien species (IAS) as being one of the greatest threats to Samoa's

Since Elton highlighted the problem of biological invasions, numerous studies have established their importance in the structural evolution of natural communities, in particular insular communities. Because of their isolation, islands are regarded as natural evolution laboratories which are characteristically very fragile once the boundary is disturbed. This fragility is illustrated by the high proportion of species extinctions observed in islands: since 1600, more than 75% of monitored disappearances have been registered in islands.

Invasive species are one of the most serious threats to biodiversity. Up-to-date and accurate information on the distribution of invasive species is an important biosecurity risk analysis tool. Several databases are available to determine the distributions of invasive species and native species. However, keeping this information current is a real challenge. Ants are among the most widespread invasive species. Five species of ants are listed in the IUCN list of damaging invasive species, and many other species are also invasive in the Pacific.

Pohnpei and their outer islands are very vulnerable to the introduction of Coconut Rhinoceros Beetle (CRB) because the CRB is present in Guam, Palau, Hawaii and South Pacific. Pohnpei is located near Guam, Palau and Hawaii and there is regular traffic by air and sea. For this reason it is very important that Pohnpei has a good Emergency Response Plan (ERP) in place not only for control/eradication but also for prevention and spread to other islands.

Economic impacts from invasive species, conveyed as expected damages to assets from invasion and expected costs of successful prevention and/or removal, may vary significantly across spatially differentiated landscapes. We develop a spatial-dynamic model for optimal early detection and rapid-response (EDRR) policies, commonly exploited in the management of potential invaders around the world, and apply it to the case of the Brown treesnake in Oahu, Hawaii.