A landscape ecological vegetation map of the island of Bonaire, southern Caribbean
A semi-detailed landscape-based vegetation map (scale 1:50,000) is presented for the southern Caribbean arid island of Bonaire (mean annual precipitation is 463mm). Color aerial photographs (1:8,000) taken in 1995 and 1996 were used to produce the map. A total of 302 vegetation sample plots were analyzed using a stratified random sampling design and twinspan cluster analysis.
A total of 18 vegetation types, and 32 (sub-)landscape types were distinguished. The three principal vegetation types, Casearia tremula-Prosopis juliflora type (Type 17), Croton flavens-Haematoxylon brasiletto type (Type 14) and Prosopis juliflora- Opuntia wentiana type (Type 16), account for 40% of total vegetation cover. The four principal landscape types also cover 40% of the island and are: D3 (Prosopis- Casearia Landscape), TH1(Haematoxylon-Croton Higher Terrace), D2 (Haematoxylon- Casearia Landscape) and TM7 (Acacia-Croton Middle Terrace). The vegetation on the volcanic Washikemba Formation is more uniform than that on the limestone forma- tions. Most of the vegetation types can be categorized as secondary. This is consid- ered mainly to be the result of the impact of introduced grazing mammals (principally goats and donkeys) and woodcutting in the past. Six vegetation types are considered of relatively high natural value. Three of these (Types 1, 9, and 10) are comparable to Stoffers’ less degraded communities. The other three have been selected based on cri- teria such as structural complexity, diversity and number and rarity of rare species.
A comparison with a vegetation map from the 1950’s shows that three types of areas can be distinguished: areas in which the vegetation has remained more or less the same, areas in which the vegetation shows improvement and areas that show broadscale de- terioration of the vegetation. The largest area that shows deterioration is the southern part of Bonaire. The northern part of the Washington-Slagbaai National Park is the largest area with improvement. The findings are discussed in relation to the Nature Management Plan for Bonaire and conservation recommendations are made.