A species has been brought back from the dead, after being declared extinct in the 1920s.
The Australian Lord Howe Island stick insect was thought to be gone forever, but international conservation efforts have proven that the species is now officially alive again, Science Alert reports. DNA testing of the insect proved the happy find conclusive.
When black rats were introduced to Lord Howe Island by a shipwreck in 1918, the consequences proved disastrous for many of the island’s wildlife. One of the populations that was wiped out was Dryococelus australis, among five bird species, two plants and 12 other invertebrates that were not found anywhere else on the planet.
In the 1960s, rock climbers on Ball’s Pyramid some 12 miles southeast of the island stumbled upon what looked to be a collection of fresh insect bodies resembling the stick insects.
However, the species did not resemble any of those recovered from Lord Howe Island, so the species was declared extinct in 1986.
Then in 2001, a small number of the insects were found living on tea trees on Ball’s Pyramid, which led to a large, captive breeding program. DNA testing has finally confirmed that these insects truly are D. australis, resulting in an extremely rare success story for a species.
Alexander Mikheyev, lead researcher and a professor at Okinawa Institute of Science and Technology Graduate University, said, “In this case, it seems like we’re lucky and we have not lost this species forever, although by all rights we should have.” He added,
We get another chance – but very often we do not.
While the insects from Ball’s Pyramid did not resemble the Lord Howe Island specimens, genome comparisons revealed a less than 1% difference, which is small enough to declare them of the same species.
The stick insects may be reintroduced to the island eventually, after a rat eradication project that is due to begin in 2018.
The insects are still considered critically endangered, but they are no longer on the list of 868 extinct species due to human causes on the IUCN Red List.
Mikheyev said, “The stick insect illustrates the fragility of island ecosystems, and in particular, how vulnerable they are to manmade change like invasive species. It just took one shipwreck, and the fauna of the island has been altered in such a fundamental way.”
The study was published in Current Biology.