Overview of Current Threats

The major threat to survival of West Indian iguana populations is habitat loss, a problem affecting virtually all taxa. This process takes a variety of forms, including conversion of dry forests for mining (Dominican Republic, Jamaica), agriculture (Dominican Republic, Grand Cayman, Lesser Antilles), charcoal production (Dominican Republic, Jamaica), timber extraction (Dominican Republic, Lesser Antilles), tourist resorts, housing developments, and other real estate ventures (Bahamas, Turks and Caicos, Cayman Islands, Cuba).

An inevitable consequence of this disturbance is the arrival of human-commensal species which can act as unnatural predators or competitors for native species. While feral cats and mongooses primarily threaten juvenile iguanas, dogs are capable of preying on adults. For some taxa, particularly the Jamaican, Lesser Caymans, and Anegada Island iguanas, predation by introduced species appears severe enough that population recruitment is very low, with few juveniles present in the wild. Among smaller species of iguanas, predation by introduced rats on juveniles and feral cats on all age classes can similarly lead to depressed population growth. Egg predation by feral pigs is a significant problem on Mona, Andros, parts of Cuba, and possibly Jamaica. Because they trample nesting sites and decimate the native vegetation on which iguanas depend, feral livestock also pose a serious threat, particularly on Anegada, Mona, Booby Cay in the Bahamas, in parts of the Turks and Caicos and the Dominican Republic, and throughout the Lesser Antilles. On some of these islands, overbrowsing has stunted vegetation and produced radical changes in species composition.

Table 3.Current Threats to West Indian iguana populations.

Hunting is also a threat for several taxa, although the reasons for this exploitation are varied. In Haiti, the Dominican Republic, and the Lesser Antilles, iguanas are hunted primarily for food, whereas in the Bahamas and the Turks and Caicos, illegal poaching for international trade is becoming an increasing concern. Finally, on islands undergoing very rapid urbanization, particularly the Caymans and some of the Lesser Antilles, road casualties are a significant cause of death for both adults and juveniles.