Institute of Marine Biology warns of invasive Pacific oyster risk

The Institute of Marine Biology at the University of Montenegro has issued an urgent appeal to shellfish farmers in the Bay of Kotor. The institute advises extreme caution regarding the import, storage, and trade of the Pacific oyster (Magallana gigas) to prevent it from entering the natural marine environment.

Although economically significant, the Pacific oyster is an invasive species in the Adriatic Sea. Its high adaptability, rapid growth, and immense reproductive potential pose a major ecological risk. A single female can release tens or hundreds of millions of eggs, which fertilize in the water and develop into larvae that settle on various surfaces.

Because these oysters can spawn directly in the sea during cultivation, they risk creating free-living populations outside of farms. This risk is already evident in the northern and northeastern Adriatic, where the species has already formed dense natural populations.