Two Wings of Terror

I present to you a creature that sounds like it was plucked straight out of a legend. A giant raptor believed to have had a wingspan of roughly 3m (10ft) (Wingspan, 2012)(Warne, 2002), it is a bird that would be perfectly at home in the Lord of the Rings universe.

Though no longer soaring through our skies, Haast's Eagle (Harpagornis moorei) (Wikipedia, 2013)(Holdaway, 1991) was as real as could be, and is possibly the source behind the Maori legend of the monstrous man-eating Pouakai aka. Hokioi (ICR, 2009) (Wehi et al, 2009) (Wingspan, 2012). So, not the sort of creature that would be found flying over the mighty peaks of the Iron Mountains and rescuing Thorin and company from goblins, or plucking Gandalf from the top of the Isengard.

An artists depiction of the Haast's Eagle attacking the New Zealand Moa - image via Wikipedia Commons

I mentioned these amazing birds briefly in my last post, Bird Extinction: The Pre-Industrial Picture. Until humans colonised New Zealand, the only predator of the giant Moa (more than ten-times the eagles' weight) were Haast's Eagles which inhabited the South Island and went extinct at the same time as their primary source of food (Wingspan, 2012).

As is the case with many extant birds of prey, the females were believed to be the larger of sexes with a standing height of almost a metre (Brathwaite, 1992). With a weight of over 14kg for females (Brathwaite, 1992), this monster predator is believed to have been capable of reaching top speeds of approximately 50mph (80 km/h)(Wikipedia, 2013) at which it "...could hit its prey with the force of a 35-pound concrete block dropped from an eight-story building" (Warne, 2002). At such speeds, it would grasp its prey at the rear, as indicated by claw marks on Moa pelvic bones (Holdaway, 1991), and deliver a killing blow to head or neck. 

As a result of it's size, it has also been suggested by scientists that the Haast's Eagle was very near the threshold for flapping flight (BBC); had they been much larger, they would probably have had to rely on gliding. By keeping their wings relatively short and their tails long for their size, the eagles were able to maintain the ability to navigate swiftly through the forests as they hunted (Holdaway, 1991)(Brathwaite, 1992)(Wingspan, 2012). So, good news for a hungry Haast's Eagle, but bad news for any Moa or the unfortunate human...