The River Foyle and tributaries
Area of Special Scientific Interest (ASSI) include the River Foyle and its tributaries i.e. that part of the River Finn which is within Northern Ireland, the River Mourne and its tributary the
River Strule (up to its confluence with the
Owenkillew River) and the
River Derg, along with two of its sub-tributaries, the
Mourne Beg River and the
Glendergan River. The area encompasses 120 km of watercourse and is notable for the physical diversity and naturalness of the banks and channels, especially in the upper reaches, and the richness and naturalness of its plant and animal communities. Of particular importance is the population of
Atlantic Salmon, which is one of the largest in
Europe. Research has indicated that each sub-catchment within the system supports genetically distinct populations. ==References==