BirdLife IBA Factsheet

Country/Territory

Montserrat (to UK)

Administrative region(s)

Central coordinates

16^o 45' North 62^o 12' West Map

Area

1112 ha

Altitude

150 - 741m

Criteria

A1, A2

Site description This site is the largest remaining forest area on Montserrat, forming a single, almost continuous block of hill forest in the centre of the island. A series of small, steep streams (known locally as ghauts) radiate from central ridges. The boundary goes beyond the forest reserve to include areas where the Montserrat Oriole is found. There is a transitionfrom tropical deciduous forest in the drier lowlands (especially on the eastern and north-eastern sides), through semi-deciduous and evergreen tropical forest at higher altitudes to elfin forest on the summit of Katy Hill. The majority of the forest is secondary, having been cleared foragriculture during the plantation era. The frequent passage of hurricanes ensures that there is a range of successional stages. Most of the area is steep and pathless. Apart from small agricultural and banana plots around the periphery, the area is little used or visited by humans. It forms the main water catchment for the inhabited area of the island, and recently several trails have been cleared to allow tourists to explore the area.

Birds The vast majority of the world population (thought to be 200 to 400 pairs) of the Critically Threatened Montserrat Oriole is resident in the Centre Hills. The Vulnerable Forest Thrush also occurs at relatively high densities throughout, and this site may well be the world stronghold for the species. The Near-threatened Bridled Quail-dove is also common. Seven other restricted-range species of the Lesser Antillean EBA are relatively common: the Purple-throated Carib, Greenthroated Carib, Antillean Crested Hummingbird, Brown Trembler, Scaly-breasted Thrasher, Pearly-eyed Thrasher and the Lesser Antillean Bullfinch. The Centre Hills is the major site on the island for most of these species. The main exceptions to this are the Green-throated Carib and the Lesser Antillean Bullfinch, which are more common in the surrounding lowlands. Pearly-eyed Thrashers and Antillean Crested Hummingbirds are abundant throughout Montserrat in all habitats. Brown Tremblers, Montserrat Orioles and Bridled Quail-doves are confined to the Centre Hills and Roche's Forest (MS003). Point count monitoring carried out between 1997 and 2003 indicates that populations of most species have increased in recent years. Exceptions to this are the Montserrat Oriole and Brown Trembler, both of which showed indications of a population decline during the monitoring period. Most of the key species are found in all forest types in the Centre Hills. The Purple-throated Carib reaches highest densities in dry forest, and the Pearly-eyed Thrasher is most abundant in lowland areas. The Montserrat Oriole occurs primarily in mesic and wet forest, and is scarce in dry forest. At around 19 birds ha-1, densities of the Pearlyeyed Thrasher are among the highest in its range (Arendt, in press).

Protection status The Centre Hills area, although largely privately owned, is a forest reserve. Species protection is provided for by the Wild Birds Protection (Amendment) Ordinance (1987). A new proposal to declare the Centre Hills a National Park, and develop a site management plan is in the early stages of preparation.

Conservation issues Introduced ship rats Rattus rattus are abundant in the Centre Hills, at least in some years, and appear to have increased during the period of volcanic activity; the causesof their population fluctuations are unknown. They are known to predate the nests of Montserrat Orioles and to predate mountain chicken; they probably have a profound effect on many other species and on the ecology of the forest. Feral pigs are spreading rapidly through the forest from the south-east, having escaped from abandoned farms in the volcanic exclusion zone. They have already destroyed large clumps of Heliconia caribea (the preferred nest plant of the Montserrat Oriole) along streams in the south of the Centre Hills. They may be significant predators of mountain chickens and other wildlife, and there is particular concern that they may predate the critically threatened Montserrat galliwasp, which appears to be extremely rare and to have a tiny range. Their effects on forest plant communities are unknown, but may be significant. Feral cats are present in the forest, and are known to predate Forest Thrushes. Their abundance and impact are difficult to assess at present.Much of the forest vegetation is secondary, and is also subject to the impacts of introduced rats, pigs and goats. There are known to be a number of non-native plants present, but their distribution, abundance and impact is unknown. It is therefore possible that the plant communities are far removed from the natural state, whichwould undoubtedly have consequences for animal communities. However, plant community ecology has not been studied.Although a native species, the exceptional density of Pearlyeyed Thrashers may also be a conservation problem. The abundance of planted fruit trees and the proximity ofagricultural plots may be a key factor permitting them to become so abundant; as a result, they are major nest predators of the nests of Montserrat Orioles and the Forest Thrush. Ash falls from the still-active volcano in the south of the island may continue to affect the ecology of the Centre Hills, particularly through the arthropod die-offs that result from heavy falls. Heavy falls also result in the physical destruction of the nests of Montserrat Orioles, and may have direct health impacts on bats and herptiles, though these impacts are poorly understood. Although most of the land is privately owned, there is relatively little pressure for forest clearance in the Centre Hills, and the importance of the forest cover for watershed protection is widely realised. However, small-scale encroachment around the fringes, both for housing and agricultural development, appears to be increasing.The boundary of the existing forest reserve does not take in all oriole sites. There are plans to extend it in the future, after consultation with landowners, to take in orioles thatare currently outside the boundary. Since the evacuation of the southern portion of the island, the Centre Hills now provides the water resources for the increasing human population of Montserrat. As a result, there has been an increase in spring-capping. The resulting reduction in stream flows may lead to increased dessication in valley bottoms. The ecological effects of this are unknown, but may be important for birds during the dry season, and also for herptiles. There is currently minimal bird hunting in the Centre Hills. However, applications have recently been made to begin hunting, and the law currently permits hunting of the Near-threatened Bridled Quail-dove, which is likely to be very vulnerable to hunting pressure, and for which Montserrat is probably a major stronghold.

Recommended Citation BirdLife International (2009) Important Bird Area factsheet: Centre Hills, Montserrat (to UK). Downloaded from the Data Zone at http://www.birdlife.org on 10/2/2010