The year is 1959. Speleologists descend a 17-metre shaft to explore the depths of Mairs Cave in the southern Flinders Ranges. Some 55 metres into the main chamber, they find fossils scattered throughout a boulder pile. Among these fossils are a claw and part of a wing bone that appear to have come from a large eagle.
Over a decade passes. An expedition to the cave, led by naturalist Hans Mincham and palaeontologist and geologist Brian Daily, now arrives with the purpose of retrieving more fossils. Among the many mammal fossils they recover are another talon and most of a large bird breastbone – from the same large eagle.
No more fossils of this animal are found until more than 50 years later. It is December of 2021, and a team of Flinders University palaeontologists and speleologists have travelled to the cave for a single purpose – to find more of this enigmatic bird. As they descend into the cave’s depths, they hope to find a few more bones. Instead, they find a partial skeleton, including leg and wing bones, and a skull. With this last discovery, we were finally able to name and describe this gigantic eagle in the Journal of Ornithology.
Only two larger eagles ever existed anywhere: Gigantohierax suarezi, which hunted giant rodents in Cuba, and the giant Haasts eagle, Hieraaetus moorei that hunted large moa in New Zealand.
Thanks to the relatively complete skeleton from Mairs Cave, we were able to identify other fossils of Dynatoaetus from the Naracoorte caves in South Australia and the Wellington caves in New South Wales. It appears this species was widespread across most of southern Australia.