Ancient Footprints Reveal Tasmanian Tigers Once Roamed Eyre Peninsula
New archaeological evidence has surfaced, suggesting that the iconic Tasmanian tiger, or thylacine, once traversed the rugged landscapes of South Australia’s Eyre Peninsula. These marsupial carnivores, known to early European settlers for the distinctive stripes adorning their backs, vanished from mainland Australia approximately 2,000 years ago. By the time European colonisation began, their numbers had dwindled to a mere 5,000 individuals confined to Tasmania, with the last known thylacine succumbing to extinction on September 7, 1936.
The discovery of preserved footprints along the Eyre Peninsula’s coastline offers a fascinating glimpse into a vastly different Australian ecosystem from millennia past. A dedicated team from Flinders University, spearheaded by palaeontology lecturer Aaron Camens, meticulously examined a series of ancient tracks in the vicinity of Coffin Bay and Lincoln National Park earlier this month.
Their investigation focused on the Bridgewater Formation, a geological feature spanning South Australia characterised by calcified coastal dune ridges dating back to the Pleistocene era. These ancient formations act as time capsules, preserving a rich tapestry of fossilised footprints and other remnants of prehistoric life.
Dr. Camens described the geological formations encountered as resembling “pancake stacks,” with distinct, layered sediments. “Wherever you see them on the coast, they can look kind of like a pancake stack, lots of individually layered sediments, and these sediments actually have fossil footprints occurring in them right across the south coast of Australia, and we were looking for those in Eyre Peninsula,” he explained.
The process by which these fossils are formed is quite remarkable. According to Dr. Camens, sea spray would settle on animal tracks left in the sand. As this saltwater dried, it would form a hardened salt crust. This crust would then be rapidly covered by windblown sand, effectively preserving the imprint of the original footprint within the sediment layers.
The Bridgewater Formation is known to host a diverse array of ancient fauna. “There’s a huge range of animals represented,” Dr. Camens noted. “We do have elements of the megafauna; there are extinct kangaroos. We rarely find animals like thylacoleo (marsupial lion), sometimes some big relatives of the giant herbivore Diprotodon, but we also find some of the smaller animals, so things like Tasmanian devils and thylacines. We even get smaller animals all the way down to things like birds, like oystercatchers.”
The Fragility and Elusiveness of Fossil Discoveries
Despite their historical significance, these ancient footprints are incredibly vulnerable to the forces of nature. “We do actually see them being regularly eroded, so especially if they’re right on the coast and there’s a big swell hitting it all the time,” Dr. Camens warned. “We might see that the footprints might be exposed for only a few years and then they’re destroyed, but then new ones are exposed as well.”
The research team found some footprints near Coffin Bay in areas less affected by erosion, allowing them to be observed with relative stability. However, other locations, such as parts of the south coast of Lincoln National Park, are subjected to powerful swells, leading to a constantly changing environment.
Accessing these fossil sites can also present significant challenges. “Quite often they’re in hard-to-get-to places,” Dr. Camens stated. “The best areas that we find these in are actually areas that are being smashed by the waves, so they could be cliffs 20 metres high, so they can be a bit unstable, so they’re not necessarily in the safest place to look at.”
Local Knowledge and Identifying Ancient Tracks
Retired national parks ranger Ross Allen has been aware of fossil sites on Eyre Peninsula for two to three decades and played a crucial role in sharing this knowledge with the university researchers. “If you get to the right location at the right time, you can sometimes [find] hard layers of sandstone that have impressions from over 100,000 years ago,” Mr. Allen explained. He emphasised the immense value of these discoveries: “So much can be learnt from those sorts of fossil remains in South Australia, particularly on Eyre Peninsula, from way back in time when all sorts of animals roamed around that no longer exist.”
Identifying thylacine tracks specifically can be a complex task, often requiring expert knowledge. Mr. Allen noted that the prints are easily eroded and may not always be distinct. “For thylacine prints, they’re just a circular impression that is obviously, once you know what you’re looking at, made by a dog species, and there were no dingoes back over 100,000 years ago, so the only animal that existed back then that could have made it is a thylacine.”
Dr. Camens highlighted the importance of recognising repeating patterns to confirm the identification of a species’ trackway. “You might not see something that you can clearly say, ‘Oh, yeah, that looks like a thylacine print, or that looks like a kangaroo print,'” he said. “But if you see a repeating pattern, with the same shapes and the same spacing between them, then that means you’re probably looking at a trackway.” The footprints examined in this study are estimated to be between 110,000 and 130,000 years old.
Mr. Allen believes these fossil discoveries present a valuable opportunity for the public to connect with and appreciate the natural heritage of the coastline. He urged for greater care and protection of these sites. “Our wildlife is under threat constantly from, you know, impacts, human impacts, particularly on habitat and clearing vegetation, so people need to be aware that they can play a big part in looking after the future welfare of important wildlife.”
The Australian Museum confirms that fossilised remains of thylacines have been found not only across the Australian mainland and Tasmania but also in Papua New Guinea, underscoring the species’ once extensive range across the region.
