Nijman, V.

Abstract:

In 2005 to 2006 we assessed the status of the Caribbean coot Fulica caribaea in the Netherlands Antilles, largely semi-arid islands in the South Caribbean, with small numbers of permanently available fresh water bodies. The Caribbean coot is a freshwater bird which is dependent on the seasonal availability of freshwater ponds for breeding; it breeds on 4 of the 6 islands of the Netherlands Antilles, viz. Curaçao (first recorded in 1956), Bonaire (1974), Aruba (1977), and St. Maarten (1981). Compared to the period up to and including 1979, group sizes in 1980 to 2006 were larger on Curaçao, and it appears more abundant in the latter period on all islands. We report on 49 sites (>5 ha) in the Caribbean where the species has been recorded, or where we would expect it to occur on the basis of available habitat. Threats to the Caribbean coot include drainage or reclamation of habitat, hunting, and pollution. Few sites receive protection. The coot has a restricted range of occupancy of some 1000 km2, spread out over 13 islands, representing 10 countries. Based on its restricted range, coupled with high levels of threat and the limited amount of protection, we recomend that the species be included as ‘Vulnerable’ in the IUCN (International Union for the Conservation of Nature and Natural Resources, World Conservation Union) Red List. An increase in the level of (legal) protection, in addition to an increase in the amount of habitat included in the regional protected areas network and heightening the awareness of the needs of this Caribbean endemic are overdue. The establishment of permanent freshwater ponds, especially in the arid parts of its range, appears favourable for the species, and may aid conservation. 

Abstract:

We conducted an ichthyological survey during the dry season of 2006 on the semi-arid islands of Aruba, Bonaire and Curaçao to provide information on species composition, richness and dis- tribution in natural and non-natural aquatic habitats. The dry season species assemblages (N = 9 species) comprised less species than the wet seasons, and these data refine our knowledge of the indigenous fish fauna and its refuge localities during phases of drought and ensuing high salinity. A hierarchical cluster analysis reveals that the three islands have different species compositions with Curaçao being the most diverse, probably due to its having the most habitats and freshwaters present throughout the year. Species richness was unrelated to salinity and species diversity was highest in canalised streams. In the dry season fewer amphidromous species are present than in the wet season. We found no significant effect of human-induced changes on the presence or absence of fish species in the Netherlands Antilles. The presence of exotic species (including Xiphophorus helleri on Aruba, a first record for this island, and Oreochromis mossambicus and Poecilia reticulata occurring on all three islands) did not have a clear effect on the presence of indigenous species, nor did human alteration of the habitats have an influence on the occurrence of fish species. 

Abstract:

We conducted fieldwork on Bonaire and Curaçao, Netherlands Antilles, to assess the distribu- tion and abundance of resident diurnal raptors. In total, seventy-three 1 km2 sample plots were selected following a stratified random method and three landscape types were distinguished, i.e. cultivated area, hills and terrace. The diurnal raptors observed were the Crested Caracara Caracara plancus (93 records), White-tailed Hawk Buteo albicaudatus (37), and the American Kestrel Falco sparverius (44 on Curaçao only). In the hills and on the terraces, all species were more abundant on Curaçao than on Bonaire. Caracaras were found significantly more in hills compared to terraces or cultivated land on both islands, as did White-tailed Hawks on Curaçao. The American Kestrel made more use of cultivated area and least of hills. As detection of the raptors did not seem to differ between the landscapes and between the islands, we infer that the observed differences in distribution are a true reflection of their habitat use. Our results suggest that the ongoing urbanization on Curaçao and Bonaire may lead to a decline in the Caracara and the White-tailed Hawk. For the American Kestrel, cultivated areas – including urbanized parts – apparently provide the open area the birds need for hunting.