Only 10 of the small silver porpoises are left on the planet, but genetic studies offer new hope.
Read moreBy Helen Briggs
Environment correspondent
By Helen Briggs
Environment correspondent
A cotton-top tamarin monkey has made its first public appearance at Cali Zoo in Colombia.
Patricia Oyella
BBC News, Kampala
The Ugandan authorities say they have detained a Congolese national found transporting 122 African grey parrots in the western district of Kisoro.
The suspect was arrested with the birds crammed into two cages during a joint operation by the police, the Uganda Wildlife Authority (UWA) and the army.
UWA spokesman Bashir Hangi said they acted following a tip-off that parrots were being smuggled from Kinshasa, the capital of the Democratic Republic of Congo, to Uganda.
Three parrots had died when the man was arrested in Kibaya village near the border town of Bunagana.
The suspect is now being held at the Central Police Station in Uganda's capital, Kampala.
The parrots have been taken to the Uganda Wildlife Conservation Education Centre.
African grey parrots, native to rainforests in central Africa, are listed as an endangered species by the International Union for Conservation of Nature (IUCN).
Loss of habitat and large nesting trees have had a significant impact on their numbers.
They are one of the most heavily traded wild birds because of their ability to mimic human speech.
The Guardia Civil found more than 1,000 specimens including extinct and endangered species.
By Nick Eardley
BBC political correspondent
After a dramatic decline in numbers, Australia's koala has been listed as "endangered".
Two out of five wild plants are threatened with extinction. Today people are finding remarkable ways to help them, and so make our world a little greener and a little wilder.
By Jonah Fisher
Environment correspondent
Karli and Nieva arrived at the zoo in December 2020 in the midst of Covid restrictions
By Vanessa Buschschlüter
BBC News, Glasgow