Virgin Islands
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Important Bird Areas in the Caribbean – US Virgin Islands ■ US VIRGIN ISLANDS LAND AREA 353 km2 ALTITUDE 0–477 m HUMAN POPULATION 106,000 CAPITAL Charlotte Amalie IMPORTANT BIRD AREAS 9, totalling 62 km2 IMPORTANT BIRD AREA PROTECTION 90% BIRD SPECIES 210 THREATENED BIRDS 4 RESTRICTED-RANGE BIRDS 7 JIM CORVEN (BRISTOL COMMUNITY COLLEGE) Great Pond IBA on St Croix. (PHOTO: LISA D. YNTEMA) INTRODUCTION and cays is primarily dry forest, including closed-canopy forest, woodland and shrubland. Subtropical moist forest (with a The US Virgin Islands (USVI), an organised, unincorporated continuous canopy and an abundant herbaceous understorey) United States territory, are at the eastern end of the Greater is found in the uplands (where annual rainfall is above 1,200 Antillean chain of islands in the northern Caribbean Sea, and mm), along drainage ghauts or streams and in some coastal basin comprise three major islands and more than 50 offshore cays. areas (accounting for c.10–15% of the land area). USVI also As an archipelago, the Virgin Islands are politically divided supports grasslands, a variety of wetlands, and a full range of between USVI (the south-western group of islands) and the coastal zone habitats. However, all have been subject to human British Virgin Islands (which stretch out to the north-east). disturbance or development as well as natural effects of tropical However, St Croix (the largest of the three main islands at 217 storms. From the times of pre-ceramic aboriginal settlement to km2) lies about 65 km to the south of the rest of the Virgin the present day, these ecosystems have been in a constant state Islands and c.100 km south-east of mainland Puerto Rico. The of regeneration and succession. Virtually no primary forest two northern islands of St Thomas (74 km2, and c.60 km east exists on the islands. It has been replaced with secondary “new of mainland Puerto Rico) and St John (50 km2) are very hilly forest” that has regenerated following the cessation of (high points of 477 m and 387 m respectively) with limited flat plantation agriculture. Wetland habitats include salt ponds, salt areas. St Croix is a much flatter and drier island, with fewer flats, mangrove wetlands (the only legally protected habitat in bays and offshore cays. Offshore cays collectively make up c.3% USVI), mixed swamp, and freshwater ponds (all of which are of the territory’s area (12 km2). man-made for livestock or landscaping). Despite their extremely The USVI climate is categorised as subtropical or dry tropical. high value to both humans and wildlife, many of the natural Average annual rainfall is 750 mm in coastal areas and up to wetlands have been destroyed or lost to development. 1,400 mm at higher elevations. Annual rainfall patterns are erratic, but on average, peak rainfall periods are September– ■ Conservation December with a brief wet “season” in May or June. The dry There are two primary pieces of legislation that apply to the season is January–April. The resultant vegetation on the islands protection of wildlife in USVI: the Virgin Islands Indigenous 329 Important Bird Areas in the Caribbean – US Virgin Islands and Endangered Species Act (1990), and the federal US public) sponsored by the Audubon Club of St Thomas and Endangered Species Act (1972) under which Brown Pelican the St Croix Environmental Association (SEA); and numerous Pelecanus occidentalis, Piping Plover Charadrius melodus and other conservation and awareness activities conducted by Roseate Tern Sterna dougallii are listed. A proposed SEA, USFWS, the St Croix East End Marine Park and the modification of the territorial legislation (VI Endangered and Environmental Association of St Thomas. Indigenous Species Act), with lists of USVI species considered Although the only wildlife habitat that is legally protected under various categories of threat, is presented in the in the USVI is mangrove woodland, there are numerous “Comprehensive Wildlife Conservation Strategy”. The protected areas provided by both territorial and federal Division of Fish and Wildlife (DFW) is the key public agency governments, and private organisations including The Nature for research and monitoring of birds and habitats in the USVI. Conservancy, Island Resources Foundation and SEA. All They have directed or collaborated in extensive studies on all federally owned cays are protected within the Virgin Islands the islands that have documented the status of seabirds and, National Park, Hassel Island National Monument, Buck to a lesser extent other species. Working with US Dept. of Island National Monument, or as National Wildlife Refuges. Agriculture, DFW has undertaken eradications of rats and The territorial government has designated Flat Cay, Little goats from important seabird breeding colonies on DFW- Flat Cay, Saba Island, and Turtledove Cay as wildlife reserves. managed cays. They are also looking at exotic plant More recently, legislation has been drafted that would result management with the National Park Service (NPS), and in all 33 cays owned by the territorial government being collaborate with US Coast Guard, US Fish and Wildlife designated as wildlife sanctuaries. The 18 privately-owned cays Service (USFWS), US Geological Survey, The Nature are not protected and are therefore vulnerable to development Conservancy and others to implement their work. The NPS and disturbance. However, USVI’s small islands or cays are is responsible for all land and marine areas within the St John considered major seabird nesting habitat because of their Park which it monitors regularly and within which it has natural isolation from land predators and (mostly) human completed numerous biological inventories. The University disturbance. Projects have been implemented to eliminate rats of the Virgin Islands (UVI) provides local logistics for a (Rattus spp.), invasive plants, and goats from a number of number of offshore projects, plus GIS and data management these islands, benefiting not only the seabirds but also the sea- expertise, and technical advice. The author has also established turtles that nest on the beaches of several cays, and other landbird surveys based on numerous point counts. With reptiles such as the globally threatened St Croix ground lizard support from Cornell Lab of Ornithology, a public website Ameiva polops and the endemic Virgin Islands tree boa (www.ebird.org/usvi) has been made available for researchers Epicrates monensis granti. and birders to submit observations and retrieve data regarding The islands’ human population is growing and has caused birds of the USVI. Other conservation and research initiatives the extensive loss and degradation of natural habitats, most on the islands include work by the Island Resources severely on densely populated St Thomas, but with other islands Foundation (IRF); field station facilities managed by the suffering too. For example, Krause Lagoon—once the largest Clean Islands International at the Virgin Islands (260 ha) and most important mangrove wetland on the south Environmental Resource Station; Christmas Bird Counts and side of St Croix—was destroyed in the 1960s to make way for Breeding Bird Surveys coordinated by the Audubon Society industrial expansion. Industrial complexes and residential and of St John and by unaffiliated individuals on St Croix; commercial development are destroying and fragmenting native educational birding trips (for school groups and general forest. Residential development, hotels, resorts, and marinas Brown Pelicans are listed under the Federal Endangered Species Act. (PHOTO: CAROL CRAMER-BURKE/ST CROIX ENVIRONMENTAL ASSOCIATION) 330 Important Bird Areas in the Caribbean – US Virgin Islands have been constructed on coastal wetlands, and marine recreational activities have damaged vital mangroves, coral reefs, and sea-grass beds. Human development has increased air and water pollution, and encouraged the introduction of exotic plants (for landscaping) and animal pests (especially domestic cats, dogs, and chickens that roam or become feral). Many domestic septic systems are not maintained or do not function and contaminate bays with sewage. This human- induced destruction and fragmentation has left ecosystems less able to absorb natural threats such as hurricanes (e.g. Hugo in 1989 and Marilyn 1995) and tropical storms. With rapid changes taking place to the natural environment there is a clear need for further habitat protection, increasing the level of environmental awareness (at government and public levels), monitoring the populations of key bird species, enhancing institutional resources and capacity, identifying critical conservation areas (not yet covered by the IBA network), and implementing conservation actions such as invasive species Young White-crowned Pigeons—significant numbers breed at eradications and species reintroductions. Great Pond IBA, but the territory’s population is unknown. (PHOTO: CLAUDIA C. LOMBARD/USFWS) ■ Birds Of more than 210 species of birds recorded from USVI just Viable populations of two globally threatened species occur 60 are resident breeding species and over 130 are migrants of in USVI, namely the Near Threatened Caribbean Coot Fulica which most are Nearctic breeders. Of the c.60 Nearctic– caribaea and White-crowned Pigeon Patagioenas leucocephala Neotropical landbird migrants recorded from the islands, 30 (see Table 1). The population of P. leucocephala is unknown are vagrants. About 20 species of warbler over-winter on the on USVI (although along with the Bridled Quail-dove islands, primarily in the mature continuous forest on St John Geotrygon mystacea it appears to have partially recovered in (especially the upper elevations of north-facing dry forests), recent years). Fulica caribaea occurs, albeit in small numbers, the Bordeaux Mountain moist forests on St Thomas, and the as a breeding species on St Croix with non-breeding birds forested north-west quarter of St Croix. Seven of the 27 Puerto found on the other main islands. They are outnumbered almost Rico and the Virgin Islands EBA restricted-range birds still 2:1 by American Coot F. americana, with which they form occur in the islands (see Table 1), none of which is endemic to mixed colonies.