Introduction
Species of conservation concern
Scotland supports some of the strongest remaining populations in Europe of a number of vulnerable animal species. These include the Atlantic salmon, three species of lamprey (sea, river and brook) and the freshwater pearl mussel. All these are found in Northern Europe and beyond but many have declined to such an extent that Scotland is now considered to be a stronghold for their remaining populations.
The salmon, pearl mussel and lampreys are all linked by a river's complex 'web of life' whereby each can be dependent on another for its continued survival. Very young pearl mussels rely on the presence of young salmon in the river for their survival, and some species of lamprey depend on salmon and other fish species as a food source. In turn, both pearl mussels and young lampreys feed on small particles in the river water, and abundant populations of these species may help to maintain the cleanliness of river systems needed by other animals, including salmon