Habitat loss and fragmentation were historically most extensive on the least mountainous areas, which were systematically cleared for agriculture. As tourism and other economic growth superseded agriculture in importance, (coastal) development has further reduced the remaining habitat and significantly affected already-limited communal nest-sites (Day et al. 2000). Road casualties occur regularly along coastal road, which bisect iguana habitat.
Lesser Antillean Iguanas are impacted by a range of introduced predators. Predation by both cats and dogs is a large problem. Adult iguanas are known to be killed by guard dogs that run free within fenced properties where iguanas move to feed.
Free-ranging and feral browsing competitors are present on St. Eustatius. Goat and cow populations are particular large and of most concern. Extensively overbrowsing continues to cause a shift in plant species composition and habitat structure. Another threat is the ongoing degradation of natural vegetation attributable to the spread of invasive alien species, most notably the Mexican Creeper (Antigonon sp.), which is unpalatable to both goats and iguanas (Fogarty et al. 2004; Debrot et al. 2013).
Hunting is likely a minor problem, primarily because population densities are so low that it is not worth the effort. Other notable sources of iguana mortalities are starvation (or drowning) in abandoned cisterns and entanglement in fencing.
Displacement through competition and hybridization with the common Green Iguana (Iguana iguana) appears to be the dominant factor in the disappearance of the Lesser Antillean Iguanas in the region. This proces is rapid and subsequent population extirpations have been recorded from several islands in the French West Indies. Sadly a single green iguana female was discovered in early 2016, along with another 6 hybrid iguanas on St. Eustatius since. Hybridization is now considered the main threat for the lesser antillean iguanas existance throughout its natural range. The introduction of green iguanas and hybrids has to be prevented at all costs!
Overview
Documented death or endangerment of iguanas in St. Eustatius, April-December 2012 (source: Debrot et al. 2014, Herpetological Review 45(1), p129)
Dogs: 10 death, 1 rescue
Traffic: 3 death, 0 rescue
Cistern: 1 death, 4 rescue
Fencing: 0 death, 6 rescue
Hunting: 2 death, 0 rescue
Unknown: 1 death, 0 rescue
Total incidents of 28 individuals in 2012.