Extinctions ‘may threaten Madagascar’s biodiversity for 23 million years’

Dr Lesley Dickie from the Durrell Wildlife Conservation Trust explains the situation in Madagascar and what can be done to protect endangered species there.

It may take millions of years for Madagascar to recover from extinctions caused by human activity, according to a new study.

The island in the Indian Ocean is home to over 200,00 species and around 90% of these are not found anywhere else on earth.

But unless rapid conservation action is taken, scientists warn these animals are threatened with a wave of extinction - and it could take much longer to recover from this than previously thought.

The island is home to animals like the ring-tailed lemur and the aye-aye.

Over three million years of evolutionary history have already been lost from the island and researchers predict that if the island's threatened mammals go extinct it will take another 23 million years to recover from this.

Field biologist Steve Goodman, who is a researcher in Madagascar, said: "It’s abundantly clear that there are whole lineages of unique mammals that only occur on Madagascar that have either gone extinct or are on the verge of extinction.

"If immediate action isn’t taken, Madagascar is going to lose 23 million years of the evolutionary history of mammals, which means whole lineages unique to the face of the Earth will never exist again."

He added: "There is still a chance to fix things, but basically, we have about five years to really advance the conservation of Madagascar’s forests and the organisms that those forests hold."

For the study, the researchers created a data set of all the mammals known to live on the island in the last 2,500 years.

The team then created family trees to work out how the species are related to each other and how long it took them to evolve, before collating this to estimate how long it would take for new mammals to evolve in their place if they went extinct.

Luis Valente, a biologist at the Naturalis Biodiversity Centre and the University of Groningen in the Netherlands, said that their 20 million-year estimate is "much longer than what previous studies have found on other islands, such as New Zealand or the Caribbean".

Around 250 mammal species were living on the island when humans first arrived there, but at least thirty of these have since gone extinct.

Since the 1980s, Durrell has been working to protect some of these endangered animals at Jersey Zoo.

In 2020, an endangered aye-aye was born at the zoo and in 2022 the world's rarest duck - the Madagascar pochard - was saved from extinction thanks to Durrell's efforts.