Anguilla Bank Bush Anole

Anguilla Bank Bush Anole

These anoles are of small to moderate size for the genus, with a maximum known head-body length of 50 mm in males and 42 mm in females. They are slender and have relatively long snouts, superficially resembling Greater Antillean “grass-bush” anoles. Variation in colour is very pronounced in these lizards. The colour and pattern of the back and tail in adult males range from grey-brown with distinct crossbands on the neck and body to an almost uniform tan with a yellowish cast to the sides and markings on the lower sides that may or may not be evident. The head may have a reddish cast or be suffused with blue. Bright sky-blue markings are most evident around the eyes. Females and juveniles are dull grey-brown with a tinge of yellow on the lower sides visible while they are light. Some females have a faint, light line down the middle of the back. Blue colour on the head and crossbands may or may not be evident but, even when present, is less well defined than in males. Bellies in both sexes are light grey or tan. Skin and scales of the males’ dewlaps are white, with a little grey sometimes present along the back edge.

Distribution and Origin:  These lizards currently are locally abundant on St. Maarten. For reasons unknown, they have disappeared from Anguilla and might or might not have occurred on St. Barthélemy. Close relatives (Anolis schwartzi and A. wattsi), once thought to be subspecifically related, occur on the St. Kitts and Antigua banks. All probably are descendants of ancestors that arrived in the region from the Greater Antilles. Although this species adapts to human-altered conditions, occasionally enters homes and other human-made structures, and is known to occur in dramatically altered habitats at lower elevations, these lizards are most abundant on the less intensely developed uplands and slopes, are re-invading abandoned agricultural lands, and are frequently associated with dense plantings of ornamentals in gardens and parklands.

Habitat: These slender Anoles perch on grasses, shrubs, saplings, trees, rocks, cliff faces, and human-built structures like buildings, walls, fences, arbours, water tanks, woodpiles, and trash. They also spend considerable time on the ground and may be super-abundant in shaded areas where rocks and leaf litter occur profusely. Where they coexist with Common Tree Lizards (Anolis gingivinus), the two species appear to use resources in a very similar fashion, except that the latter seem to tolerate exposed situations better than the Bush Anoles, which maintain slightly lower body temperatures and are more likely to exploit densely shaded situations.

Food: Like other Anoles, these lizards are mostly insectivorous, consuming a variety of small insects and other arthropods. On occasion, however, they will lap nectar and eat flowers and fruits.

Predators: Birds are undoubtedly the major predators on these lizards. Herons, seabirds, and even domestic fowl occasionally may catch and eat individuals, but Killy-killys and Pearly-eyed Thrashers often concentrate their attention on these abundant lizards. Snakes (Alsophis rijgersmaei) feed primarily on lizards, but constitute little threat on St. Maarten, where they have been all-but extirpated by the introduced mongoose. Anguilla Bank Ground Lizards may occasionally eat Tree Lizards that venture onto the ground, but generally are restricted to more open situations than those inhabited by Bush Anoles.

Reproduction: Like essentially all Tree Lizards, these Anoles lay one egg at a time. Egg deposition sites vary considerably and may include almost any inconspicuous location, although most probably are laid in leaf litter. Females do not remain with the eggs, which hatch in four or more weeks, depending on temperature.

Behaviour: As is typical of essentially all Tree Lizards, these Anoles are territorial. Males spend considerable time and energy establishing and defending their territories, the sizes of which vary according to the habitat and abundance of essential resources as well as the “quality” of the male and his ability to deter interlopers. However, if not engaged in aggressive or courtship behaviours, these lizards are quite shy. When approached, they will creep to the far side of a tree or branch or retreat deeper into a rock crevice. If threatened, they usually jump to another perch or to the ground, where they will run to a different rock or plant or simply disappear into the leaf litter. Only rarely will individuals climb upwards into the canopy of a tree to escape.

Tree Lizards usually sleep on leaves or twigs at heights similar to those used by day. However, many Bush Anoles sleep in rock outcroppings, under rocks, in crevices in cliffs, or in rock walls and other artificial situations.

Conservation Status: Although Red-listed as vulnerable, conservation plans focused on this species probably are not necessary at this time. However, unlike A. gingivinus, the habitat preferences of this species render them more vulnerable to alterations of natural habitats, which are becoming increasingly rare as a consequence of development.

Source: Powell, R., R.W. Henderson, and J.S. Parmerlee, Jr. 2015. The Reptiles and Amphibians of the Dutch Caribbean: St. Eustatius, Saba, and St. Maarten.

Skills

Posted on

November 28, 2016