Extinction of species

People often destroy marine habitats with their activities - when building harbours and piers, when shipping and fishing, to lay pipes or cables on the seabed or to dredge sand. This leads to the extinction of many marine animals that cannot live outside these habitats.
The Black Sea is also home to many foreign species that arrive on ships from other seas and can be a serious threat to native species because they have no natural enemy and spread quickly.