The Crested Tree Lizard (Calotes versicolor)
The first observation of C. versicolor in Seychelles dates back to the 27th of September 1982 at Barbarons on Mahe Island.
The Ministry became aware of C. vesicolor’s presence in Seychelles when staff from Anse Aux Pins clinic reported the first specimen on the 27th October 2003. The individual was apparently captured on Sainte Anne Island by a local and transported to Mahé to be kept as a pet. The lizard managed to escape and was caught about 500 m away. The good thing is that it was spotted in time by concerned individuals. A survey that was immediately conducted on the island revealed a viable population of 20-25 mature individuals in close proximity to the jetty. According to island staff, the first observed occurrence dates back towards late 2001 when the resort was near completion. Apparently the species was confined to the beachfront area where construction materials were offloaded and could have been accidentally introduced in containers from Mauritius.
The lizard comes from Southern Asia, from India to China and the provenance of Seychelles population is not really known. It is usually tan or grey with brown banded, its long tail is twice its body (length up to 40cm). Prominent crest extending from neck down to the body. Its food habitat is mainly insectivorous including ants, crickets and beetles while it also have an opportunistic omnivorous feeding habit including small vertebrates and some plant materials.
The Crested Tree Lizard can be found from sea level from 600-1000 m in dry, open shrubland and cultivated land. It favors tree trunks, rocks, wasteland, garden, parks and all man-made habitats. It uses a sit and wait hunting strategy often from a high point. It is a territorial animal. Females and juveniles tend to forage on the ground in the grassy and shrubby vegetation while the male adults stay in the open more often. They roost on vegetation (up to 9 m) at the tips of twigs, shoots and inflorescence. It is also known that this lizard is able to swim in fresh and sea water.
The Crested Tree Lizard could have an impact on any kind of birds, it preys on eggs and small birds. All endangered bird on Mahé could be threatened. The worst thing that could happen would be an introduction of this lizard on such predator free island like Aride and Bird Island.
Anecdotal observations on C.versilor behaviours have revealed very interesting information. They climb with great agility, often jumping from branch to branch. The toes are long and pointed to aid with gripping and the long tail is used for balancing. They hide behind stems and coconut palm trunks and upon approach of humans, flatten the body laterally until they are almost invisible. They are able to rotate their eyes independently of each other hence the ability to detect danger from afar. They are most active 2-3 hours after sunrise where most often territorial adults would station themselves on a conspicuous object such as a rock to display. This activity coincides with feeding. They have been observed feeding on a variety of invertebrates and vertebrates. Their diet also comprises of crickets and grasshoppers. Different instinctive methods such as the use of glue, nets and manual removal of individuals have been utilized so far. The most successful has been manual removal whereby individuals, once spotted, are flushed, pursuit until caught. The Saint Anne population is now under control and there has not been any reliable report since 2006.