A man holds a pangolin at a wild animal rescue center in Cuc Phuong, outside Hanoi, Vietnam September 12, 2016. REUTERS/Kham

Employees weigh a pangolin before its release to the forest at a wild animal rescue center in Hanoi, Vietnam September 9, 2016. REUTERS/Kham

A woman holds the scales of a pangolin at a traditional medicine shop in Hanoi, Vietnam September 13, 2016. REUTERS/Kham

A pangolin climbs on a tree at a wild animal rescue center in Cuc Phuong, outside Hanoi, Vietnam September 12, 2016. REUTERS/Kham

Frozen pangolins are seen at a wild animal rescue center in Hanoi, Vietnam September 9, 2016. REUTERS/Kham

Flamingos walk in Donana natural park in El Rocio, southern Spain, March 16, 2006. REUTERS/Marcelo del Pozo/File Photo

An Iberian lynx, a feline in danger of extinction, is seen after being released as part of the European project Life Iberlince to recover this species in Donana National Park, southern Spain, February 15, 2016. REUTERS/Marcelo del Pozo/File Photo

A group of people stand on the beach in Donana National Park, southern Spain, May 11, 2016. REUTERS/Marcelo del Pozo/File Photo