In addition to native fauna, Saint-Barthélemy is also home to invasive alien species (IAS). These are species introduced by man, whether intentionally or not, into an environment where they do not live naturally. Their presence can disrupt ecosystems, threaten local biodiversity and cause ecological and economic damage. That's why their management is essential, and you can play your part!
This iguana, originally from South America, has been imported to the island by man since 1960. Considered pets, then released into the wild or imported in plant containers from Florida, they are now well established on Saint-Barthélemy. This species threatens our local species: the Lesser Antillean iguana (Iguana delicatissima), an endemic species found only in the Lesser Antilles. The striped iguana, larger and stronger than the local iguana, competes with it for territory and food resources. It also hybridizes with it, threatening the local species with extinction, as the juveniles have the physical characteristics of a striped iguana.
If we still see Lesser Antillean Iguanas on the island, we should remember that they have totally disappeared from the islands of Saint Martin, Saint Kitts and Nevis, Barbados, Marie-Galante and Les Saintes. They have also almost disappeared from the islands of Guadeloupe and Martinique.
They can still be seen on Saint Barthélemy, Petite-Terre, îlet Chancel and Dominica.
Recognizable by its striped tail and subtympanic scales, if you see a striped iguana, call ATE immediately on +590 690 31 70 73.
This snake, native to North America, arrived on the island in plant containers imported from the USA. While it is not venomous and therefore poses no danger to humans, it is a threat to our native reptiles. By sharing the same diet as our Banc d'Anguilla snake (Alsophis rijgersmaei), it competes with the local species for food resources. Part of its diet consists of reptiles and birds, so it is a threat to our local fauna.
Recognizable by its ochre color and leopard-like spots, if you see a corn snake, call ATE immediately on +590 690 31 70 73.
This goat was imported to the island by settlers in the 17th century as a source of food for the inhabitants who settled on Saint Barthélemy. For many years, it was the island's main source of meat. Saint Barthélemy's economic boom since the end of the last century has distracted the island's inhabitants from this difficult and time-consuming activity. The goats were then released into the wild, and various hurricanes (Luis, Irma) destroyed the remaining pens.
Today, the number of goats roaming the island is estimated at around 2,000, a figure that continues to rise as a female can have two litters a year and up to 4 kids per litter. Able to eat up to 15kg of vegetation per day, the goat represents a real threat to all the island's ecosystems, including marine ones!
Indeed, local terrestrial species (insects, birds, reptiles) are greatly impacted by the lack of habitat and food due to the disappearance of vegetation.
Without vegetation, soil erosion increases with each rainfall event. On the one hand, the risk of landslides increases, and on the other, a significant amount of silt is washed out to sea with each rainfall, covering coral reefs and seagrass beds with sediment. The impact on marine flora and fauna is considerable.
The possession of goats is not forbidden, as long as they are penned for their safety and to limit their impact on biodiversity. Feeding free-roaming goats is not permitted.
If you have free-roaming goats in your garden, please contact ATE on +590 590 27 88 18 or by email: contact@agencedelenvironnement.fr
The ATE will take care of the paperwork, and the capture will then be carried out on your land in a way that respects the animal.
In Saint-Barthélemy, with increasing urbanization and changing lifestyles, many cats have been abandoned or released into the wild. Their ability to reproduce quickly has led to uncontrolled proliferation.
Today, the number of stray cats on the island is estimated at several thousand. These felines, hunting daily to meet their needs, represent a major threat to native fauna. Birds and reptiles are particularly hard hit by this increased predation. Some species, already weakened by the reduction in their habitat due to the island's current environment, are critically endangered.
In addition, the high concentration of stray cats leads to health problems: transmissible diseases, parasite proliferation and territorial conflicts.
To limit these consequences, cat ownership requires increased responsibility: sterilization and identification of pets are encouraged to limit proliferation and reduce their impact on the island's biodiversity.
If you observe stray cats in your home (without their ears cut off), the ATE provides cat cages to catch them, and the various vets on the island sterilize them at no cost, the whole process being fully paid for by the Collectivité. By 2024, over 1,700 cats had been sterilized on the island.
The domestic hen was introduced to the island by settlers as early as the 17ᵉ century to provide a regular source of meat and eggs for the inhabitants. For centuries, raising them was an essential resource for families living on Saint-Barthélemy. However, with economic development and the rise of tourism, this practice was gradually abandoned. Successive hurricanes (Luis, Irma) destroyed many chicken coops, leaving the hens to roam free and encouraging their uncontrolled proliferation.
Today, they can be seen all over the island, in all kinds of environments. In their search for food, they disrupt ecosystems by scratching the soil, accelerating erosion and impacting the natural regeneration of vegetation. Their presence also alters the ecological balance by competing with certain native species for food resources.
Furthermore, stray hens attract predators such as rats and cats, increasing pressure on native fauna, especially birds and reptiles. They can also carry diseases that affect other animals as well as humans.
Chickens may only be kept in a secure enclosure to prevent them from wandering off. Free-range feeding is not permitted.
Mice, surmulots and rats were introduced to the island as soon as settlers arrived in the 17ᵉ century, transported unintentionally on trading ships. Finding an abundance of local food and the absence of natural predators, these rodents rapidly multiplied. For a long time, their presence was tolerated, not least because they were partly regulated by domestic cats and the presence of humans. However, with environmental change and urbanization, their population has exploded.
Today, it is estimated that rats and mice have colonized the entire territory and all strata of the environment, posing a major problem for local biodiversity. Opportunistic and omnivorous, they prey on bird eggs, threaten reptile populations and consume a wide variety of seeds and plants, directly impacting vegetation regeneration. Their proliferation unbalances the ecosystem by increasing competition for food and favoring the presence of predators such as cats.
In addition to their ecological impact, these rodents pose a major health risk for residents, as they can carry diseases that can be transmitted to humans and domestic animals.
Limiting their proliferation requires responsible management of waste and food resources, as well as targeted control actions to preserve the fragile balance of the island's ecosystems.
Put your garbage in the bins provided or at the times indicated by PAPREC. Don't throw your leftover food out in the open, leave your dogs' and cats' bowls indoors and don't feed invasive species (stray cats, chickens, goats, turtles, etc.) to limit the attraction and proliferation of rodents.
The coal turtle was introduced to the island by man, mainly for dietary reasons. Originally from South America, this terrestrial turtle gradually found its way into the wild, deliberately released or escaped. In the absence of natural predators, and thanks to favorable climatic conditions, the turtle has established itself on the island and multiplied.
Today, the presence of this invasive species represents a threat to the ecological balance of Saint-Barthélemy. Opportunistic and omnivorous, the hog-nosed turtle consumes a wide variety of plants, fruits and even small invertebrates.
Its presence can encourage the dispersal of seeds of exotic plant species, facilitating the spread of other invasive species and accentuating the transformation of natural habitats. Its long life expectancy and adaptation to anthropized environments make it complex to control.
Today, it is estimated that there are 4 hog-nosed turtles for every inhabitant of Saint-Barthélemy (population 12,000). To limit its impact, it is essential to raise awareness of the need to preserve local ecosystems in the face of invasive exotic species.
Don't feed hog-nosed turtles to avoid contributing to their proliferation. Wild, hog-nosed turtles are not “domestic” animals (unlike goats or chickens), so they should not be kept in enclosures.
Invasive exotic anolis were introduced - and continue to be introduced today - via maritime trade (particularly containers of exotic plants). Originating in Cuba and the southern United States respectively, these lizards quickly colonized Saint-Barthélemy thanks to their great adaptability and the absence of natural predators. Today, their presence represents a major threat to local species. By occupying similar ecological niches, these anolis compete with endemic species, notably the Anguilla Bank Anoli (Anolis gingivinus), for food (insects and other small invertebrates) and breeding sites. More opportunistic, the Cuban Brown Anoli (Anolis sagrei) and the Carolina Anoli (Anolis carolinensis) often overtake local species, drastically reducing their populations.
What's more, their high reproductive capacity accelerates their expansion, making them particularly difficult to control.
Although their presence is currently difficult to eradicate because they are so discreet, limiting their spread is crucial to preserving the island's biodiversity. This means increased surveillance in which everyone can participate, education on the dangers of introducing exotic species, and efforts to protect local species.
Please keep an eye out for them on a daily basis, and report their presence to us by calling +590 690 31 70 73.
The lionfish, native to the Indo-Pacific, was first observed in Saint-Barthélemy in 2010. With no natural predators in this region and a remarkable ability to adapt, it spread rapidly, becoming one of the most destructive marine invaders of coral reefs.
Today, Pterois volitans represents a considerable threat to marine biodiversity. An insatiable predator, it feeds on numerous species of juvenile fish and crustaceans, drastically reducing their populations and destabilizing reef ecosystems. This excessive predation prevents the renewal of local fish populations and weakens coral reefs, which depend on certain herbivorous species to control algal blooms.
Its proliferation is all the more problematic in that Pterois volitans reproduces extremely rapidly: a single female can lay up to 2 million eggs a year, ensuring continuous expansion of the species. Its powerful venom, contained in its dorsal spines, offers protection against rare potential predators and is a danger to divers and fishermen.
In response to this threat, regulation campaigns have been set up to encourage fishing and consumption of this species. Raising awareness among divers and fishermen of the importance of catching red lionfish is essential to limit its impact and preserve the fragile balance of coral reefs.
Notice to anglers: if you catch a lionfish, do not release it alive in the water. Authorization has been granted by the ATE to hunt lionfish in the Marine park zone. To do so, you must be equipped with a fishing rod and a suitable tube.
