Newly discovered lizard species up to 3 females remaining
What species of lizard was wiped out in its natural habitat and now depends on three breeding females breeding in captivity for its long-term survival?
Oh wait, I can’t really answer that, because the species doesn’t have an official name.
For the moment it is called the orange-tailed skink. It was only discovered in 1995 and has not been fully described to date. Although it does not have an official name, it has been given a temporary scientific name, Gonglyomorphus cf fontenayibecause it resembles (“cf”) the Macchabe skink (G. fontenayi). Until recently, the species lived only on the flat island of the Republic of Mauritius, the small, isolated island nation in the Indian Ocean located 870 kilometers east of Madagascar. Unfortunately, Flat Island’s development plans for tourism have brought in another kind of guest, the highly adaptable Indian shrew (Murine suncus), which has been named one of the world’s most damaging invasive species.
Fortunately, a field team from Durrell Wildlife Conservation Trust noticed the invasive rodent-like mammals on Flat Island in 2010 and quickly rounded up all the skinks they could find. Nearly 400 of the tiny reptiles traveled to Gunner’s Quoin, an island nature reserve located between Flat Island and the main island of Mauritius. Another 22 traveled to Durrell’s headquarters in Jersey, England. These translocations were completed just in time: when Durrell staff returned to Flat Island in 2011, they found no evidence of skinks remaining. “Despite very sensitive equipment being used to survey the island, there were no more skinks,” said Rick Jones, Durrell’s communications manager. “If it weren’t for the forward thinking of our field team, the orange-tailed skink would be another statistic on the list of 40 known species that have been extinct in Mauritius since 1600.”
It’s too early to tell if the skinks that have been moved to Gunner’s Quoin will survive or thrive, but Jersey’s small population is already growing. Although the original 22 skinks only included three breeding-age females, they have been on a spawning frenzy over the past four months. Already 16 eggs have hatched and four more are incubating.
Creating a safe habitat where the skinks could breed required emulating the natural environment of Mauritius, says Jones. “We need to establish the microclimate just below the ground, the substrate where the skinks live.” This included matching temperature above and below ground, as well as varying temperature and humidity levels. “It’s extremely tricky and requires a good routine to ensure the right ‘season’ is biologically ‘on time’ for the animals,” he says. “It comes with experience and some intuition, but a daily routine of misting/spraying and pouring water in certain areas, and using lamps for heat and UV.”
Jones credits the small team led by Matt Goetz, Durrell’s new herpetology manager, with creating and successfully managing the captive environment. “It is truly his instinctive breeding methods, born out of a lifetime of interest, that have facilitated such success in breeding what is for all intents and purposes a species that could have gone extinct before anyone knew. that she existed.”
With a little luck, the three females could soon be joined by other breeders. Goetz suspects that some of the younger skinks, especially those approaching the 2.5 to 3 year old age range, could start breeding when Durrell simulates a hot and humid season.
It’s too early to tell what additional impact the invasive shrews might have on Flat Island, as the species is “very difficult to control,” Jones says. As for skinks, they usually consume arthropods and other invertebrates, themselves serving as prey for larger snakes and birds. They also help keep soil turned over and refreshed, helping to provide fresh nutrients to plants. It is not yet clear what will become of the Flat Island ecosystem without them.
For now, however, at least some of the Indian Ocean orange-tailed skinks are safe in England. Who knows, one day soon they might even have their own name.
Photo: Matchstick-sized orange-tailed skink hatchlings, courtesy of Durrell Wildlife Conservation Trust