[Many thanks to Peter Jordens for bringing this item to our attention.] Matthijs van den Burg, Julian Thibaudier and Dolfi Debrot inform the general public about two new non-native reptile species for Wageningen College & Analysis (WUR).
In 2022, two new non-native reptile species have been discovered on St. Eustatius. The 2 species involved are Underwood’s spectacled tegulet and the frequent home gecko. Each species in all probability established themselves on the island lately. The variety of non-native reptile species within the Lesser Antilles has been quickly rising over the previous years and is a significant explanation for concern for the distinctive biodiversity of the area.
Two newcomers: Underwood’s spectacled tegulet (scientific identify: Gymnophthalmus underwoodi) originates from South America and probably the most southern islands of the Lesser Antilles. Nonetheless, within the final couple of years, a number of populations have established themselves in additional northerly areas, like St. Maarten and Florida, and most lately (2021) on Saba. The present improve of non-native reptile populations is linked to move of products by sea. On St. Eustatius, Underwood’s spectacled tegu has been noticed since 2020 throughout the entire island. A particular attribute of the animal is that each one people are feminine, and no males are vital for profitable copy (parthenogenesis). Partly as a result of this technique of copy, Underwood’s spectacled tegu can multiply quickly as soon as it enters new areas or arrives on a brand new island.
Some individuals would possibly know the frequent home gecko as a daily pet of reptile hobbyists. Nonetheless, this animal additionally has a big pure space of distribution and is quite common within the wild. The unique distribution of this gecko species is in South-East Asia, but it surely at the moment happens in Australia, North and South America and St. Maarten. After mating, a feminine can carry viable sperm for as much as 36 weeks, which boosts its fecundity and helps the species set up itself quickly in new areas. The species has now been documented in St. Eustatius, the place it’s discovered together with one other Hemidactylus species, particularly the tropical home gecko (Hemidactylus mabouia). This gecko, which has been current on St. Eustatius for an extended time, can also be is non-native of the island, and originated in Sub-Saharan Africa. Prior analysis has proven that the frequent home gecko is much extra aggressive than the tropical home gecko and is understood to outcompete the latter over time. Due to this fact, it may be anticipated that the tropical home gecko will finally disappear from St. Eustatius.
Enhance in non-native animal species within the area: Lately, the variety of populations of non-native reptile species on St. Eustatius and Saba has elevated remarkably. For instance, each the Underwood’s spectacled tegulet and the brahminy blind snake (Indotyphlops braminus) have been lately discovered on Saba. This non-native blind snake had already been discovered on St. Eustatius. As well as, inexperienced iguanas (Iguana iguana) additionally often make their method over as stowaways on cargo ships.
It’s placing that the majority newly-introduced species within the area are first reported on St. Maarten, and some years in a while the encircling islands, like Saba and St. Eustatius, each of that are principally provided with supplies and merchandise from the ports of St. Maarten and Florida. These ports thus have an essential damaging position within the unfold of non-native animals within the area, and it’s pressing that extra consideration is paid to strategies and protocols relating to biosecurity.
Little is understood in regards to the affect of both species on the ecology of St. Eustatius. Nonetheless, it’s a given proven fact that the introduction of non-native animals is likely one of the largest causes of worldwide biodiversity decline. Launched crops and animals cannot solely typically outcompete the native organisms however might trigger genetic air pollution or introduce new illnesses and pests to native populations.
Iguanas: Each St. Eustatius and Saba are residence to distinctive and critically endangered iguana populations. Along with the lack of (high quality of) habitat, the introduction of non-native inexperienced iguanas has now grow to be the best menace to the way forward for the native iguana populations. The presence of a big non-native iguana inhabitants on St. Maarten, which serves as an essential supply of non-native animals hitchhiking to Saba and St. Eustatius, is especially worrisome. When these inexperienced iguanas handle to breed on Saba and St. Eustatius, except measures are taken, this may simply imply the top of the distinctive iguanas as a result of a mix of genetic mixing and competitors. As a way to defend the distinctive natural world of St. Eustatius, Saba, and different surrounding islands, it’s subsequently critically essential that biosecurity within the ports inside the Dutch Caribbean turns into [stricter].
Extra info: The institution of each species on St. Eustatius is described in an article within the scientific journal Caribbean Herpetology.
For authentic article, see https://www.wur.nl/en/news-wur/show-home/invasion-of-non-native-reptile-species-continues-in-the-lesser-antilles.htm
That is the scientific article talked about above: Julian Thibaudier, Matthijs P. van den Burg, Adam M. Mitchell and Tomas O. Cornwell (2023), “Institution of the Easy-scaled Tegulet (Gymnophthalmus underwoodi) and the Widespread Home Gecko (Hemidactylus frenatus) on St. Eustatius,” in Caribbean Herpetology 86:1-6, https://doi.org/10.31611/ch.86
http://www.caribbeanherpetology.org/pdfs/ch86.pdf