Eagles are amongst the largest and most impressive of the birds seen in the sky today. They are perhaps not as large as the eagles depicted by Tolkein or in the adventures of Sinbad, but it is actually only in the recent past that eagles larger than today’s Harpy Eagle could be seen. The largest of these extinct eagles is believed to have been Haast’s Eagle, Harpagornis moorei..
When people think of the extinction of an animal species they often presume it occurred thousands of years ago, often linking all extinction to the demise of the dinosaurs. The extinction of animal life though continues right up to the present day, although the extinction of Haast’s Eagle, a bird native to New Zealand, occurred some six hundred years ago.
Knowledge of Haast’s Eagle comes mostly from fossil finds, although Maori stories also tell of gigantic birds. The belief being that the eagle died out some two hundred years after the arrival of the Maori to New Zealand in c1200AD.
Evidence for the eagle’s existence has been found across the South Island, and indeed the bird was named by Dr Julius von Haast for George Moore, he owner of the land where the first fossils were uncovered. Fossils have provided a great deal of detail about the bird, including suggestions that the birds were found in forested areas, often with open areas nearby.
Fossils have shown though that the female Haast’s Eagle, the larger of the sex, could have weighed as much as 14kg, with a wingspan of up to 3m, making it thirty to fifty percent larger than the largest eagles alive today. The wingspan though is relatively short when compared with the length of the bird, an adaption allowing it to easily fly through dense forest. Scientists believe that the wingspan of the eagle is as large as it could be to allow for flapping flight.
Fossil evidence though has provided no clue as to the reproduction habits of Haast’s Eagles. Some details about its diet are though known, and the eagle is thought primarily to have fed upon the large flightless bird, the giant moa, Dinornis giganteus, a bird that could weigh up to 200kg. The moa would be killed by a single hit to neck or head after the Haast’s Eagle had dived on to their prey at speeds of up to 50mph. It is generally thought though that the extinction of the Haast’s Eagle came about shortly after the extinction of the moa, the moa being hunted by the newly arrived Maori.
The extinction of the Haast’s Eagle shows the impact that man can have directly and indirectly on an ecosystem, and offers warnings for other bird species today.