Tonight’s entry will be the first installment of a New Zealand twofer. New Zealand is the land of birds – it has no native mammals. Like any non-exclusively avian ecosystem, however, the islands have their share of browsers and hunters, predators and prey. They just happen to be all birds. In the coming posts, I’ll get into what some of the native predators were (and are) like in New Zealand. The answer seems to be either big and scary, or small and really scary.
Let’s start with big and scary: Haast’s eagle. Up until about 500 years ago, this beast ruled the skies over New Zealand. It weighed 40 pounds (18 kg) and had a ten foot (3m) wingspan. Before humans landed on the island 750 years ago, Haast’s eagle and the 440 pound (200 kg) flightless moa were the largest animals on the islands. When humans arrived in the Thirteenth Century and started killing off the moa, they took away the Haast’s eagle’s main food source. By the time European colonists reached the islands in the 1800s, the eagle was just a memory.
Haast's eagle takes on moa, NZ
Until recently, scientists thought Haast’s eagle mainly scavenged on dead moa. But in a September entry in the Journal of Vertebrate Paleontology, scientists from New Zealand and Australia assert that the eagle was a predator. They CT scanned Haast’s eagle skeletons and determined that while the birds lacked sensory equipment that is typical of scavengers, they had the claw nerves of an avian murderer. The verdict was that the eagle was built to kill. Specifically, the giant moas.
The idea that Haast’s eagle took down large animals dovetails with Maori tales of the Hokioi or Pouakai, giant birds of legend. Here’s one Maori description of these birds, as reported by a missionary in 1878:
“A Pouakai had built its nest on a spur of Mount Tawera, and darting down from thence it seized and carried off men, women, and children, as food for itself and its young. For, though its wings made a loud noise as it flew through the air, it rushed with such rapidity upon its prey that none could escape from its talons.”
The JVP article’s authors make a point of downplaying the described devastation: “The carrying off of men and women is undoubtedly an exaggeration,” they write. Notably, they have no objection to the idea that Haast’s eagle could have carried off Maori children.
Next up: What looks like a pretty parrot, but eats sheep alive? Answer coming tomorrow…
Who knew you read the Journal of Vertebrate Paleontology? Who knew there was a Journal of Vertebrate Paleontology? You’re doing a great job of exploring the theme in your title with humor, vivid description and lots of unusual science. Love the missionary’s report, too.