A non-native species of fish could return to Scottish rivers in large numbers this year.

Pink salmon are native to Pacific Ocean waters but have spread to parts of northern Europe after being released into rivers in Russia in the 1960s.

Fisheries Management Scotland said 2017 saw “unprecedented numbers” of pink salmon in UK rivers.

It said due to the fishes’ two-year life cycle the salmon could be seen again this year.

There are concerns the invasive species could become established in Scottish rivers and compete with native Atlantic salmon for food.