Wildlife of
Montserrat

Primary Threats

• Habitat loss is concentrated in the remaining northern and central areas outside the volcanic Exclusion Zone, where settlement and services are now concentrated (e.g., around Brades, Little Bay development). This can fragment Centre Hills forest edges and ghauts through road upgrades, small-scale clearing, and incremental development, compressing wildlife into a smaller, more vulnerable footprint.
• Volcanic processes have fundamentally reshaped southern watersheds and coastal systems: ashfall, lahars, and sediment pulses alter river channels (ghauts), bury vegetation, and increase turbidity on reefs and seagrass beds after heavy rains. Post-eruption geomorphic change can reduce habitat suitability for forest specialists and degrade nearshore marine habitats via chronic sedimentation.
• Montserrat is highly exposed to stronger hurricanes, intense rainfall events, and longer droughts. These extremes increase landslides in steep catchments, stress upland forest, and accelerate sediment runoff that smothers corals. Sea-level rise and warming seas also elevate risks of coastal erosion, saltwater intrusion into low-lying wetlands/mangroves, and coral bleaching events that reduce reef resilience.
• Introduced rats and feral cats are key threats to native birds, reptiles, and ground-nesting/coastal wildlife through predation on eggs, chicks, and small vertebrates. Invasive plants can also spread along disturbed road edges and abandoned agricultural plots, changing forest structure and complicating native habitat regeneration-especially in areas repeatedly disturbed by storms or ash deposition.
• Chytridiomycosis (Bd) has been a major driver of catastrophic declines in the "mountain chicken" frog (Leptodactylus fallax) on Montserrat, compounding vulnerability from small population size and habitat disturbance. Disease risk is heightened on islands where populations are naturally limited and recovery depends on intensive management and strict biosecurity during surveys and any translocations.
• Nearshore water quality can be degraded by sewage and stormwater runoff from concentrated northern settlements, plus plastics and debris affecting beaches and mangroves. Fine sediments mobilized from disturbed slopes (including ash-rich deposits) act as a chronic "pollution-like" stressor for reefs by reducing light, clogging coral tissues, and limiting coral recruitment.
• Fishing pressure is focused on nearshore reef-associated species and invertebrates (e.g., lobster and reef fish), with limited local reef area and resilience to absorb high offtake-especially after hurricanes or high-sediment periods. Even moderate fishing can have outsized ecosystem effects on a small island shelf where nursery habitats and reefs are spatially constrained.
• New and upgraded infrastructure in the north (roads, utilities, housing, and port-related development around Little Bay) can increase fragmentation, edge effects, and runoff into ghauts and coastal waters. Construction on steep slopes also raises erosion risks that translate directly into reef sedimentation.
• Because the south is largely uninhabitable, development pressure is spatially concentrated into a small northern area, intensifying land-use change around remaining natural habitats. This creates a 'crowding' effect where biodiversity-rich forest and watersheds sit adjacent to expanding settlement footprints.
• Extraction of volcanic sand/aggregate (where it occurs) and quarrying for construction materials can disturb riverbeds and coastal depositional areas, increasing sediment delivery to the sea and altering freshwater habitats. In a small island system, localized extraction can quickly translate to broader coastal water-quality impacts.