A little-known species of burrowing crayfish thought to be extinct has been found alive and well in creeks flowing into Lake Burbury, near Queenstown, as part of a Hydro Tasmania environmental survey.

Lake Burbury was formed in 1991 as part of the King Hydroelectric Scheme and the area is a known habitat for several endemic Tasmanian crayfish species.

The short-tailed rain crayfish (Ombrastacoides parvicaudatus) was first documented during surveys of the King River Valley in the ‘70s and ‘80s, but it was only as our understanding of these animals grew over the following decades that it became recognised as its own separate species in 2006.

With no sightings for decades, the short-tailed rain crayfish was considered to be critically endangered or even extinct, however recent field work has found the species is still present in at least two of the steep, rocky creeks on the eastern slopes of Mount Lyell.

In November 2020, Hydro Tasmania engaged Environmental Consulting Options Tasmania (ECOtas) for new survey work, joined in the field by Hydro Tasmania’s engineering consultancy Entura, which found six crayfish species at a range of sites around Lake Burbury, including the short-tailed rain crayfish at two sites.

ECOtas’ Associate Professor Alastair Richardson, formerly of the UTAS School of Natural Sciences, is a renowned crayfish expert who has spent decades studying them.

“So little is known about the short-tailed rain crayfish, it’s been difficult to make a determination on its status when for many years we were not even sure it was a separate species,” Professor Richardson said.

“But we knew their preferred habitat and remarkably, within just 10 minutes of mooring our boat at our very first target site we found our first specimen and we then later discovered a female carrying eggs, which is very encouraging.”

Hydro Tasmania Environmental Scientist Bec Sheldon said that as Australia’s largest water manager, it is essential the business has a thorough understanding of the environments it operates in.

“This field work is part of our review of the King and Yolande catchments, which give us a better understanding of the areas we use to generate renewable energy so we can manage them sustainably for everyone’s benefit,” Ms Sheldon said.

Professor Richardson is currently helping to educate Tasmanian students and communities about burrowing crayfish through the Bookend Trust's 'Claws on the Line’ program.