Alien species are those species of plants, animals and fungi that establish themselves outside their original range. However, it is important to distinguish between alien species and invasive alien species, those that, when introduced, create damage not only to the ecosystem but also to health and the economy.
In Italy there are more than 2200 alien species of animals and plants, in marine and terrestrial environments. Of these, 20% are considered invasive or potentially so. To face this problem, the Italian Zoo and Aquarium Union (UIZA) , of which Oltremare is also a member, has decided to launch the campaign 'WATCH OUT FOR THE ALIEN' to spread the need to pay attention, even in our daily actions, to this problem.
In the Alien Invasion trail in Oltremare you can observe alien species that very often harm native ones, such as the catfish and the red-eared turtle.
Common name: CATFISH
Scientific name: Silurus glanis
Length: up to 2 meters
Weight: up to 100 kg
It is a freshwater fish native to Eastern Europe, but has been introduced to many other parts of the world, where it is considered an invasive alien species. It has an elongated, cylindrical body, with smooth, scaleless skin. The head is large and flattened, and the mouth is wide and equipped with sensory barbels. Generally gray-greenish in color, it has a rounded caudal fin. It is an opportunistic predator, feeding on fish, amphibians, aquatic birds and small mammals. Its voracity and ability to adapt to different environments make it a very effective predator. It prefers rivers, lakes and ponds with calm, deep water. The female can lay thousands of eggs. Its spread is facilitated by sport fishing and accidental releases.
Its ability to reproduce rapidly and colonize new environments makes it difficult to control.
Common name: RED-EARED TORTOISE
Scientific name: Trachemys scripta elegans
Length: between 15 and 30 cm
Weight: 1.5-2.5 kg
This freshwater turtle is native to the southeastern United States. Unfortunately, due to its popularity as a pet, it has been introduced to many other parts of the world, where it has become an invasive alien species with significant impacts on local ecosystems. It gets its name from the characteristic red stripes on the sides of its head. Its carapace (shell) is oval, flattened and olive green with yellow markings. Its feet are webbed, adapted to aquatic life. In the wild, it lives in ponds, lakes, slow-flowing rivers and marshes. It easily adapts to different aquatic environments. The red-eared slider competes for food resources and habitats with native turtles, such as the European pond turtle ( Emys orbicularis ), putting their survival at risk.
It is essential to avoid the abandonment of these animals and promote knowledge of the negative impacts of invasive alien species to protect the biodiversity of our ecosystems.
it
