More than a fifth of the world's migrating species are at risk of going extinct as a result of climate change and human encroachment, according to this report by the United Nations.

Migratory species globally are facing critical challenges, with nearly half in decline and over 20 per cent threatened with extinction, a landmark UN report has pointed out. Of most concern is the threat to migratory fishes, with 97 per cent of the species on the brink of extinction. The two greatest threats to all migratory species are overexploitation and habitat loss due to human activity, according to the first-ever State of the World’s Migratory Species report.