Your Voice, Our Headlines

Download Folkspaper App with no Ads!

BULLETIN

A fast-growing newspaper curated by the online community.

The world's largest eagle dove straight into dead prey to consume the organs.

  • tag_facesReaction
  • Tip Bones

Its name means "ancient glutton" in the Mori language.


According to recent research, the largest eagle that ever lived hunted like its current relatives but feasted like a vulture.


The extinct behemoth, known as Haast's eagle, used its strong talons and beak to hold and puncture living prey. It ate its kills, however, in the manner of a vulture, cutting through the cadaver and pushing its head deep inside the body cavity to gulp down internal organs.


Scientists have long debated whether Haast's eagle (Hieraaetus moorei) was a predator, like modern eagles, or a scavenger, like vultures. Its feet and talons were similar to those of an eagle. However, vulture-like skull traits suggested that it was specialized to feed on dead animals.


Researchers recently answered this question by comparing the extinct behemoth to live birds using computer models and simulations. An examination of the birds' skulls and talons revealed which feeding habits of the extinct raptor were similar to those of eagles and which were similar to those of vultures.


According to the Wingspan National Bird of Prey Centre, a New Zealand conservation group, Haast's eagles lived in New Zealand and weighed up to 33 pounds (15 kilograms), with talons 4 inches (9 centimeters) long and a wingspan about 10 feet (3 meters) broad.


The enormous eagles mostly dined on moas, which are now extinct but were common in New Zealand until about 800 years ago. Another team of researchers revealed in 2014 that the Mori people arrived on the island about that time and began hunting moas and destroying the birds' forest habitats. Mori dubbed the enormous eagle "te hkioi" or "poukai," which translates as "ancient glutton." But it was the human demand for moas that endangered the eagles; as moa populations declined across New Zealand, so did the eagles.


Haast's eagles ate moas, according to preserved moa bones scarred by eagle beaks and talons. But did the eagles hunt live moas, which may weigh up to 440 pounds (200 kg)?


Previous research on the eagle's overall body shape and talon structure discovered similarities to eagle bodies and talons, implying that Haast's eagle was a hunter. However, questions about vulture-like skull features "such as the bony scrolls around the nostrils, which couldn't be explained by a predatory lifestyle" remained, according to Anneke van Heteren, lead author of the new study and Head of the Mammalogy Section at the Bavarian State Collection of Zoology in Munich.


The scientists created 3D digital models of Haast's eagle heads, beaks, and talons for the study and compared them to the bones and talons of three eagle species and two vulture species. They created muscle models and examined dozens of bone markers to establish which sections of the extinct raptor's feet and cranium were working the hardest while it hunted and nourished.


"When you apply particular forces to the skull, it slightly deforms, and you can see how it bends during feeding or hunting," van Heteren explained to Live Science. The researchers measured strain levels at many areas on the skull and compared them to spots in the same positions across all of the birds' skulls.


The strain values for Haast's eagles resembled those of other eagles during specific activities, such as grasping prey in a death grip with their feet, according to van Heteren. "But the neurocranium, which is where all [the] neck muscles attach — it was much more vulturelike," van Heteren said of the bird's beak, which had the potential to inflict a "death bite."


While Haast's eagle did kill its giant moa prey, it ate them in the same way as scavenging vultures devour carrion: by pushing its head inside the corpse and then tugging and gulping down organs and strips of muscle.


"These moas weren't merely dying of old age and being eaten - they were actively hunted," van Heteren explained. "However, it was hunting these much larger than itself huge moas, which caused it to feed like a vulture would on an elephant carcass."


Another characteristic Haast's eagle had in common with vultures was a bald head. The extinct bird is usually depicted in art with a feathered, eagle-like head and neck. However, in a Mori cave painting supposed to depict a Haast's eagle, the bird's body is coloured but not the head, "which we read as bald vs feathered," van Heteren added. "That certainly strengthens the concept that it was feeding like a vulture, with its head buried into its prey's slimy organs."

Comments

Loading...