A new genus and species of giant accipitrid bird being named Dynatoaetus gaffae has been identified from fossil remains found South Australia.
The Haast’s eagle (Hieraaetus moorei) attacking two moas. Image credit: John Megahan / PLoS Biology, doi: 10.1371/journal.pbio.0030020.
Dynatoaetus gaffae was a member of Accipitridae, a family of small to large birds of prey that includes eagles, hawks, and Old World vultures.
The ancient bird lived in Australia during the Pleistocene epoch, between 700,000 and 50,000 years ago.
It had a wingspan up to 3 m (10 feet) wide and powerful talons wide enough to grab a kangaroo, making it the largest bird of prey to ever live on the Australian continent.
Its size is quite large compared to most living eagles, but it is still smaller than the largest known individuals of two other distantly related extinct species: the Haast’s eagle (Hieraaetus moorei) from New Zealand and Gigantohierax suarezi from Cuba.
Dynatoaetus gaffae was closely related to Old World vultures of Africa and Asia and the critically endangered monkey-eating or Philippine eagle (Pithecophaga jefferyi).
“Dynatoaetus gaffae and the recently described Cryptogyps are new genera of raptors unique to Australia, respectively eagle- and vulture-like, that existed until around 50,000 years ago,” said Dr. Ellen Mather, a paleontologist at Flinders University.
“This discovery reveals that this incredible family of birds was once much more diverse in Australia, and that raptors were also impacted by the mass extinction that wiped out most of Australia’s megafauna.”
“It was ‘humongous’ — larger than any other eagle from other continents, and almost as large as the world’s largest eagles once found on the islands of New Zealand and Cuba, including the whopping extinct 13-kg Haast’s eagle of New Zealand,” said Dr. Trevor Worthy, also from Flinders University.
“It had giant talons, spreading up to 30 cm (12 inches), which easily would have been able to dispatch a juvenile giant kangaroo, large flightless bird or other species of lost megafauna from that era, including the young of the world’s largest marsupial Diprotodon and the giant goanna Varanus priscus.”
“It also coexisted with still living species such as the wedge-tailed eagle (Aquila audax), which has interesting implications.”
“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,” Dr. Mather said.
“Otherwise, it would have been directly competing against the giant Dynatoaetus gaffae for those resources.”
The first fossil remains of Dynatoaetus gaffae were collected from Mairs Cave in Flinders Ranges, South Australia, in 1956 and 1969, and comprised a sternum, distal humerus and two ungual phalanges.
A further 28 bones from this individual — including the neurocranium, vertebrae, furculum, and additional wing and leg bones, most of which were incomplete — were discovered at the site in 2021.
This allowed identification of additional fossils from the same species in collections from Cooper Creek in the Lake Eyre Basin, Victoria Fossil Cave and Wellington Caves.
“We were very excited to find many more bones from much of the skeleton to create a better picture and description of these magnificent long-lost giant extinct birds,” Dr. Mather said.
“It’s often been noted how few large land predators Australia had back then, so Dynatoaetus gaffae helps fill that gap.”
The discovery of Dynatoaetus gaffae is described in a paper in the Journal of Ornithology.
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E.K. Mather et al. A giant raptor (Aves: Accipitridae) from the Pleistocene of southern Australia. J Ornithol, published online February 15, 2023; doi: 10.1007/s10336-023-02055-x
