Haast’s Eagle

I saw an interesting show about New Zealand recently. Much of the content referred to things I already knew about, at least generally, but there was some new and interesting information as well. As one would imagine, before humans found it, New Zealand was colonized only by creatures that could reach it by air or sea. For the most part, it was inhabited by birds. Since there were no predators, particularly snakes or mammals, a lot of flightless birds evolved. Flying takes up a lot of energy, and since there was no need to fly to escape predators, many species evolved away from that ability. Under these circumstances, the Moa evolved. The Moa was the largest bird ever known to man, which the first humans on the island of New Zealand hunted to extinction about 750 years ago.

The most interesting thing I learned was that along side the Moa evolved a bird large enough to prey on it – the Haast’s Eagle. I had never heard of this bird before. The females were the larger of the sexes and weighed 30 lbs. The wing span was 10 feet, which apparently is small for that weight, but was better for the dense forest terrain it hunted in. They were actually big and strong enough to take down Moas, which themselves were about 12 feet high and weighed around 550 lbs. According to the narrator, the power of the eagle when it hit its prey from a dive was the equivalent of a cinder block dropped from an eight story building.

Now, enter the humans, also large, upright-walking prey, matching the eagle’s hunting pattern. I don’t know if there is actual evidence that it happened, but an eagle that size accustomed to such large prey could easily take down a human. It would certainly be frightening to share habitat with such a predator knowing that you would be an easy kill by its standards. Imagine living in a world where you had to be worried about being taken down and eaten by a giant bird. It’s the stuff of horror stories.

The wikipedia article on the Haast’s eagle also implies that the Maori, the original human settlers of New Zealand, may have been threatened by a bird of this size. The Moa article has some interesting information as well.