Small island states and invasive alien species

Abstract

In the world of plants, nature has always exploited various strategies vectors to ensure the widest possible distribution of propagules. Economic plants have been intentionally introduced across continents and oceans. Seeds that contaminated by other seeds often do not find any natural biological control proliferate and displace the local flora. Trade and flow of persons, particularly through tourism, provide unintentional vectors. These alien species disturb the local ecological balance not only at the expense of local flora resulting in loss of biodiversity, but can also result in considerable economic loss. Small islands are particularly exposed to such risk primarily because of the limited number of species amongst which one can find proportionally for their size a higher incidence of endemic species. The displacement of endemic species can result in the extinction of unique species which would be a loss for ever. As trade is identified as one of the major paths of introduction, the international conventions regulating trade have been discussed to provide a better understanding of the parameters within which states have to operate to control such unwanted introductions for the possible setting up of pre-border/pre-entry strategies. The primary aim is to evaluate the effect that these alien species are having on small island states and their ability to fight back these introductions. Also, focusing on four representative island states, an attempt has been made towards trying to establish whether there exists a statistical correlation between the original native range of species and the country of origin of the primary trading partners or their main tourist markets. The results of this study do not show any direct correlation. The possible reason behind this is that while there is not direct correlation with the native range, plant alien species have dispersed so much that an introduction is as much possible to occur through third countries where the alien species has established itself