The JNCC database contains 40 introduced species for Montserrat.

Problems with invasive non-native species

The volcanic eruptions of the 1990s have affected the spread of certain non-native species. Extensive pig (Sus scrofa) control work has been undertaken but further efforts are needed to stop the population growing further. The pigs are known to uproot many native plants, including (Heliconia spp.), which are the main nesting plant for the critically endangered Montserrat oriole (Icterus oberi). They also have other impacts such as trampling and predation of turtle nests (Varham 2006). Rats (Rattus spp.) are widespread on the island and are major predators of local biota and may also affect vegetation dynamics. Feral cats, goats and other livestock also present conservation problems and overgrazing and competition from alien invasive weeds is seen as limiting regeneration.

Cane Toads (Bufo marinus) have been introduced and are widespread and abundant. Although they do not appear to compete directly with Mountain Chickens they do act as a reservoir for the chytrid fungus.

In the northern part of the island in the Silver Hills large areas of scrub are dominated by Purple Allamanda (Cryptostegia madagascarensis), a garden escapee introduced from Madagascar.

Non-native Sus scrofa

Native critically endangered Icterus oberi

Priority invasive non-native species and actions

The Montserrat Department of Environment has instigated a new animal control programme with two marksmen from the UK Food & Environment Research Agency being contracted to work with local shooters and hunters with dogs to reduce the numbers of free-roaming pigs, cattle, sheep and goats.

Thin strip of image show tree trunk and bark