Chalk-stream salmon could become an official sub-species

Chalk-stream salmon should be officially classified as a sub-species, new research suggests. Scientists from the University of Exeter and INRAe (France) carried out detailed genetic testing of salmon from 42 rivers in England, Ireland and France—including fish from chalk streams in southern England and northern France.They found that salmon from chalk streams are closely related to each other—and genetically distinct from salmon in nearby non-chalk rivers.