According to the latest scientific data, 26 invasive species have been discovered in the Black Sea, the Bulgarian press agency BTA reports. Nine of them are crustaceans, and the rest are part of the zoobenthos, said Professor Valentina Todorova from the Institute of Oceanology of the Bulgarian Academy of Sciences, who together with Professor Assoc. Kremena Stefanova presented a report on the state of the marine ecosystem along the coast of Bulgaria.

Invasive species can pose a risk to biodiversity, Todorova also argued. She recalled that estimates of their presence in the marine habitat have ranged from 41 to 293 species over the years. However, according to the latest data, the number of invasive marine species in the Bulgarian Black Sea coast is 26.

Two of the invasive species have a strong impact on the local biodiversity and food chain of the Black Sea – Rapana venosa (veined rapana) and Mnemiopsis leidyi (jellyfish species).

The rapana sea snail was introduced to the Black Sea in the 1940s. About 15 years later, this species of predatory mollusk became widespread on the coast. The appearance of these snails is associated with the disappearance of edible oysters and a sharp reduction in the populations of black abalone (abalone – a type of sea snail) and molluscs. Currently, the distribution of rapana along the Bulgarian coast is limited to a depth of about 45 meters, with the largest population between 10 and 20 meters.

A carnivorous species of zooplankton-eating jellyfish, Mnemiopsis leydi, was first identified (in the Black Sea #) in the early 1980s. which compete for food. After 1995, another species of comb jellyfish, Beroe ovata, also carnivorous, was introduced (in the Black Sea No. Other alien species of zooplankton were found in the Black Sea, but they can be considered as a food resource for some fish species. (Source: Agerpres)