A blind golden mole that glides through sand has been rediscovered in South Africa, 87 years after wildlife experts feared it had gone extinct.
After a two-year search relying on DNA samples and a sniffer dog, a team of conservationists and geneticists from the Endangered Wildlife Trust (EWT) and the University of Pretoria have successfully located what’s known as De Winton’s golden mole among sand dunes in the northwest of the country.
The elusive species hadn’t been officially sighted since 1936, and prior to that was only ever found in the small region of Port Nolloth in the northern Cape. About the size of a mouse or hamster and with a shimmering coat that mimics the sand, they are difficult to spot at the best of times. On top of this, they live in largely inaccessible burrows, rarely leave tunnels behind them, and have acutely sensitive hearing that detects movements from above ground.
To detect the species, scientists instead relied on samples of environmental DNA (eDNA) – the DNA that animals shed as they move through the environment, such as skin cells, hair or feces.
“Extracting DNA from soil is not without its challenges, but we have been honing our skills and refining our techniques – even before this project – and we were fairly confident that if De Winton’s golden mole was in the environment, we would be able to detect it by finding and sequencing its DNA,” said Samantha Mynhardt, conservation geneticist with the Endangered Wildlife Trust and Stellenbosch University, in a press release.
During an expedition in June 2021, the team surveyed up to 18 kilometers (11 miles) of dune habitat a day, and – using the help of a trained scent-detection dog named Jessie – collected more than 100 soil samples from sites along the northwest coast where golden mole activity was detected. From this, they determined that several species of golden mole were present in the area.
The challenge was pinpointing if De Winton’s golden mole was one of them. Common species, such as Cape golden mole and Grant’s golden mole were easily identifiable, but since there was only one De Winton’s golden mole reference DNA available, the team could not confidently identify it. They had to wait for nearly a year, until a second gene sequence for the species, from a specimen housed in a Cape Town museum, became publicly available.
Bingo, it was a clear match.
The team was ecstatic. “Though many people doubted that De Winton’s golden mole was still out there, I had good faith that the species had not yet gone extinct,” said Cobus Theron, senior conservation manager for EWT and a member of the search team, in the press release.
A paper detailing the team’s findings published this week in the Biodiversity and Conservation journal. It notes that while the sampling demonstrated that the species may be widespread along the west coast, it is in low abundance and could be threatened by habitat loss due to diamond mining in the area. Conservation action is “both critical and urgent” to protect the populations, it adds.
The golden mole project was in partnership with conservation group Re:wild, as part of its Search for Lost Species program, which aims to locate species whose status is unclear. De Winton’s golden mole is the 11th of its “most-wanted lost species” rediscovered since the program launched in 2017.
Christina Biggs, manager for the Search for Lost Species, said in the release that the success of the search speaks to the persistence of the EWT team: “They left no sandhill unturned and now it’s possible to protect the areas where these threatened and rare moles live.”
The detection method could also bring hope for future missions around the world. “Now not only have we solved the riddle, but we have tapped into this eDNA frontier where there is a huge amount of opportunity not only for moles, but for other lost or imperiled species,” said Theron.