iHerp Australia Issue 11 | Page 47

some distance from the track. Lastly, there’s the Virgin Island Tree Boa (Epicrates monensis granti). These nocturnal constrictors, with a brownish base colouration and blotchy dark spots, meld well with their surroundings as they hunt for sleeping lizards. During the day, they curl up in termite nests, or amongst rocks or other refuges. Under favourable conditions, small islands can support high densities of this species, however, introduced mammalian predators have had a profound impact upon the boas. A captive breeding program was instigated in 1985, and since then Virgin Island Tree Boas have been successfully reintroduced on two islands. 4. The three of us meandered along the nicely- maintained boardwalk, bordered on the one side by brackish estuarine marshland and bushes. “Beware of the Jack Spaniards,” Renata warned. “They’re hornets that have a very nasty sting which will swell up for a week.” Almost instantly, we notice Brown-throated Parakeets (Eupsittula pertinax), roosting on the branches of the Sea Grape, a coastal tree, and feasting on its edible purple fruit. The decimated red mangroves, strangely twisted and gnarled, close in on the walkway. “Look, there’s a Crested Anole!” Renata directs our attention to a rather nondescript, light-grey lizard. “It’s a male,” she concludes, pointing to the ridge along its spine. There are two subspecies of Crested Anole; Anolis cristatellus cristatellus is originally from Puerto Rico and neighbouring islets, while A. c. wileyae hails from the islands to the east of Puerto Rico, including the US and British Virgin Islands. The species has also been introduced to Mexico, Costa Rica, Dominica and Florida, and is common in the pet trade. Overall colour varies from rusty-red to black and light grey. Sometimes Crested Anoles are mistakenly referred to as chameleons because of a limited ability to change colour according to their mood or temperature. Males will aggressively defend ‘the anoles of the Caribbean have adopted similar forms independently upon many different islands.’ their territories, and can resort to caudal autotomy to Edward Willliams to coin the term ‘ecomorph’ in evade predators. 1972, to describe groups of anole species that appear to be similar in general morphology and Through repeated instances of convergent evolution behaviour, and that occupy an identical niche based upon similar niche habitats, the anoles of the habitat, but that may not be closely related. Six Caribbean have adopted similar forms independently Anolis ecomorphs have been identified based upon upon many different islands. This prompted Ernest microhabitat, and the concept has also been