A team of researchers led by scientists from the Western Australian Museum has identified two new populations of one of WA’s rarest and most bizarre animals, the blind cave eel.

The finds were made in two locations in the remote Pilbara region of Western Australia.

The blind cave eel, Ophisternon candidum, is one of Australia’s least-known fishes and is the longest cave fish in the world, growing up to 40cm long.

It is one of only three Australian vertebrates known to be entirely restricted to underground waters such as caves and wells. 

A slender fish and apparently adapted to a life in darkness, it has no eyes, no scales, no fins and unpigmented white or pink skin.

The blind cave eel was first discovered nearly 60 years ago and has rarely been seen since.

“The Pilbara finds are an exciting discovery—the blind cave eel is a bizarre and enigmatic species that most people have probably never heard of,” says Dr Glenn Moore, WA Museum’s Curator of Fishes and the leader of the research team that studied the eels.

“In fact, they are not true eels at all, but belong to small family of mainly freshwater fishes that all have long slender eel-like bodies.”

The first of the recent finds was at Bungaroo Creek near Pannawonica in the inland Pilbara, where four fish have now been found.

The second population was found on Barrow Island, some 60km off the Pilbara coast, where another four fish were found.

The blind cave eel was first reported from the cave system of Cape Range peninsula, near Exmouth in 1959.

Over the next 50 years, the species was rarely seen and thought to be restricted to less than 100km of caves on the coastal plain of Cape Range.

This recent research by the WA Museum team has been published in the journals Marine and Freshwater Research and Ichthyological Research.

By analysing anatomical and genetic data, the WA Museum team showed that these new populations are exactly the same species as those found at Cape Range in 1959, despite the hundreds of kilometres of distance between them. 

“The populations were probably once linked through ancient geological and underground water connections between these sites,” Dr Moore says.

“The genetics suggests that the populations probably don’t mix with each other now. They almost certainly can’t cross between rivers in the arid Pilbara or move via the sea, so they are now effectively isolated from each other.”

The new specimens, which are now housed in the collection of the Western Australian Museum, will contribute to the study of the biology of the species, telling us more about where they live and how they change as they grow.

“We now know that the tiny juveniles have a small amount of eye pigment that is lost in the adults,” Dr Moore said, “but we still have so much more to discover and there is a need for management and conservation strategies specific to each population.”

 

Media contact

Tony Malkovic

Acting Communications and Media Manager, Western Australian Museum

+61 8 6552 7803

tony.malkovic@museum.wa.gov.au