More than 60,000 years ago, giant eagles were flying around Australia with a wingspan of nearly 3 meters (9.8 feet) across. They are thought to be the largest birds of prey ever to live on the continent and possibly the largest continental eagles in the world, according to new research.
This giant raptor from the Pleistocene era has been described from new and existing fossils found in 1956, 1969, and 2021. It was given the name Gaff’s powerful eagle (Dynatoaetus gaffae) after extensive research of Mairs Cave in South Australia.
Initially in 1956 and 1969, only a sternum, distal humerus, and two ungual phalanges were found. However in 2021, a further 28 bones from the individual were discovered, though most of them were incomplete. Inside the cave the team managed to find a fragment of distal humerus that was able to be reattached to the bone found over 50 years before in 1969.
“After half a century, and several delays caused by the pandemic, the expedition with volunteers from the University’s Speleological Society found a further 28 bones scattered about deep among the boulders at the site indicated by one of these museum relics,” said Flinders University palaeontology researcher Dr Ellen Mather in a statement.
These further fossils allowed other bones previously found in three different locations to be recognized as members of the same species. The hind limbs of the bird suggest that the species was a predator, and may have been Australia's largest known bird of prey. The researchers reckon it could have lifted a small kangaroo or koala with its powerful talons.
Given the size of a small kangaroo is around 50-70 kilograms (110-154 pounds) this means these ancient eagles – just like the Great Eagles of Tolkien's Middle-earth – could have lifted Frodo and his hobbit pals with ease, as they are only around 1.2 meters (4 feet) tall and theoretically would have weighed significantly less than that.
The team suggest that the Gaff’s power eagle coexisted in time with the still extant wedge-tailed eagle (Aquila audax) and would have limited the distribution of that species. The team think the ancient eagle would have had a wide distribution, from the dry areas of inland Australia to the more temperate coastal regions, and was likely the top avian predator during this timeframe.
“Given that the Australian birds of prey used to be more diverse, it could mean that the Wedge-tailed Eagle in the past was more limited in where it lived and what it ate,” continued Dr Mather. “Otherwise, it would have been directly competing against the giant Dynatoaetus for those resources.”
Researchers suggest that the species became extinct in the megafaunal mass extinction around 50,000 years ago along with a scavenging vulture species Cryptogyps lacertosus.
The study is published in the Journal of Ornithology.