Nature Notes – Ascension Island’s terrestrial reptiles

11 May 2022

Conservation

When thinking of Ascensions reptiles the first thing that comes to most people’s minds are green turtles. And so they should! Ascension Islanders are incredibly lucky to share the island with one of the largest green turtle rookeries in the Atlantic. But these aren’t the only reptiles found at this UK overseas territory. As well as hawksbill turtles that feed along the coast and the odd passing leatherback and loggerhead turtle, there are also three terrestrial reptiles which were more than likely brought to the island accidently by humans.

Sand lizards

Liolaemus wiegmannii, commonly known as sand lizards, are a native of South America and were first recorded in Ascension in the early 1940’s. It is not known how or when this small, pale coloured lizard arrived on Ascension, but it was undoubtedly brought by humans.  Its current distribution on island is unknown but it was found to be common in desert and semi desert habitats during the 1980’s. This photo was taken last year at Devils Riding School while exploring with the Ascension Island Cub group.

Coconut palm gecko

The coconut palm gecko, Hemidactylus mercatorius, was first identified in Ascension in 1959. It was likely to of been imported accidentally, although it is possible it conceivably reached the island by rafting from Africa. It is now commonly found scaling the walls of buildings all over the island while feeding on mosquitoes, spiders and ants.

Cuban Brown Anole

The Cuban Brown Anole, Anolis sagrei, is the most recent reptile species to make Ascension its home. It was officially recorded here in January 2017 and is now found across the entire range of climatic conditions available on Ascension. The origin of the population remains unknown, although it is presumed it arrived by air or sea freight coming in from the USA.

The Cuban Brown Anole is native to Cuba (as the name suggests) and the Bahamas. Through pet escapes and being transported accidently by planes and ships they have now spread to large areas of the USA including Georgia, Florida, Texas, southern California and Hawaii.

This well-known invasive species has a brightly coloured throat fan know as a "dewlap”. They will flair out their dewlap during courtship behaviour or when it encounters something that it perceives to be a menace or danger.

Geckos are famous for sticking to walls but how do they do this? 

Their bulbous toes are covered in hundreds of tiny microscopic hairs called setae. Each setae split off into hundreds of even smaller bristles called spatulae. When electrons from the gecko hair molecules and electrons from the wall molecules interact with each other they create an electromagnetic attraction which allows them to stick to almost any surface.