Lesser Antilles

Abstract.– Intraspecific diversity is among the most important biological variables, although still poorly understood for most species. Iguana iguana is a Neotropical lizard known from Central and South America, including from numerous Caribbean islands. Despite the presence of native melanistic I. iguana populations in the Lesser Antilles, these have received surprisingly little research attention. Here we assessed population size, distribution, degree of melanism, and additional morphological and natural history characteristics for the melanistic iguanas of Saba, Caribbean Netherlands based on a one-month fieldwork visit. Using Distance sampling from a 38- transect dataset we estimate the population size at 8233 ±2205 iguanas. Iguanas mainly occurred on the southern and eastern sides of the island, between 180-390 m (max altitude 530 m), with highest densities both in residential and certain natural areas. Historically, iguanas were relatively more common at higher altitudes, probably due to more extensive forest clearing for agricultural reasons. No relationship was found between the degree of melanism and elevation, and few animals were completely melanistic. Furthermore, we found that body-ratio data collection through photographs is biased and requires physical measuring instead. Although the population size appears larger than previously surmised, the limited nesting sites and extremely low presence of juvenile and hatchling iguanas (2.4%), is similarly worrying as the situation for I. delicatissima on neighboring St. Eustatius. The island’s feral cat and large goat population are suspected to impact nest site quality, nest success, and hatchling survival. These aspects require urgent future research to guide necessary conservation management.

Abstract

We describe a new species of Thecadactylus from the Caribbean island of Sint Maarten. The new species differs from all other species in the genus by having a distinct dorsal pattern of numerous irregular but sharply deliminated black spots and blotches on an otherwise almost patternless background.

Environmental Protection In the Caribbean (EPIC) carried out breeding seabird research in the Lesser Antilles between February and June 2009, to determine the abundance and distribution of breeding seabirds within the archipelago. The research spans two years, with the study continuing in January to July 2010. This allows each island to be surveyed both in the winter (February‐mid April) and summer (May‐ July) breeding seasons.

The basis for the project was the limited existing data on breeding seabird populations in the Lesser Antilles. Many islands had never been systematically surveyed, had incomplete data sets or only anecdotal accounts. Research was, therefore, undertaken in the following islands: St. Maarten, Saba, St. Eustatius, St. Kitts, Nevis, Montserrat, Antigua, Barbuda, St. Lucia, St. Vincent and the Grenadines, Grenada and the Grenadines. It is intended that breeding surveys will be completed in Sombrero, north of Anguilla in 2010 (they were not undertaken this year due to inclement weather). Similarly, it is planned that Dominica will be included in 2010. It was not surveyed in 2009 due to the perception that data was extant, which was later confirmed incorrect. Anguilla, St. Barthelemy, Guadeloupe, Marie‐Galante, Martinique and Barbados have complete seabird data and were not surveyed by the team. Existing data from these latter islands will be incorporated into the Atlas.

The research will form the Seabird Breeding Atlas of the Lesser Antilles. A hard copy will be given to all participating countries in the study area, generally to the government. The data will inform the Society for the Conservation and Study of Caribbean Birds (SCSCB) Waterbird Conservation Plan and will be available to the public on the web at the West Indies GIS and OBIS/SEAMAP. The study involved an ongoing literature review of breeding seabird records within existing papers, books and articles, as well as gathering information held in libraries and bird group archives. Anecdotal information from fishermen and other interest groups was also noted. This was particularly interesting in the case of the nocturnal Audubon’s Shearwater, when locations were suggested for historic colonies that were otherwise hard to locate within the time frame of the study. Information on egg poaching and other threats to seabirds was also forthcoming as well as anecdotal trends in seabird numbers.

The field work included collecting data on the number of breeding seabirds and threats to their populations on every island within the study area. Consistent methods were used and documented to allow repeat surveys in the future.

Outreach included presentations and meetings with governments and interest groups, education at schools, and media campaigns. A permit to undertake the non‐obtrusive research was obtained in every participating country. Katharine Lowrie (Project Manager), David Lowrie (Captain and Surveyor) and Megan Friesen (Research Assistant) undertook the research.

Since the publication of a checklist of Lesser Antilles’ orchids not far of twenty years ago, the orchid family has been the subject of many studies and publications, including extensive taxonomic revisions, thanks to the use of molecular tools and to the improvement of data availability through Internet (virtual herbariums on line). The knowledge of his family and on its distribution has been largely improved. The analysis of these new data and of in situ intensive prospections has given a number of 138 species recorded in the Lesser Antilles (in March 2012), 130 of them being native. This apparently stable number compared to the 1993’s checklist comes from the suppression of some species and the addition of others. It is also a consequence of taxonomic changes for around one third of the taxa. Guadeloupe remains the richest island with 103 recorded species, followed by Dominica, with 90 species and Martinique with 80 species. Examination of all the types specimen on one island’s endemics does not support the endemism level sometimes described. There are only 5 true one-island endemic species, 3 to Guadeloupe (Basse Terre), one to Dominica and one to Montserrat. The rate of endemism in the Lesser Antilles is 16%, and 27% of the Lesser Antillean orchids are endemics to the West Indies.