The Terrible Bird
from the book, "Petrified Lightning"

Petrified Lightning

The Terrible Bird

In October 1769 Captain James Cook stood on deck as his ship, the Endeavour, approached New Zealand. There he is said to have observed a huge bird on the beach; it turned and ran into the woods. If this tale is true, Cook was the only European to have ever seen a live giant moa.

New Zealand, a living museum of natural wonders, was a fitting home for such an unusual bird. Its two main islands, North Island and South Island, were once part of Gondwanaland, the supercontinent of the Southern Hemisphere. But somewhere between 60 million and 70 million years ago, New Zealand broke away from the rest of the world and became two isolated islands that "drifted" to their present position. The isolation of the islands produced a rare and distinctive flora and fauna. Today three—quarters of New Zealand's indigenous plants live nowhere else on earth. Its fauna, likewise unique, include living fossils such as the tuatara, a lizardlike reptile more ancient than the dinosaurs. All native birds are flightless, including a parrot that makes its home in underground burrows like a rabbit.

Before the arrival of humans, New Zealand was free of all predators, so the birds, having no enemies, lost the use of their wings. Then the Polynesian Islanders arrived, by accident in the 10th century and for the purposes of colonizing with the arrival of the Great Fleet about a.d. 1300. These Maori, with their dogs and (inadvertently) their rats, were the predatory mammals for whom flightless birds became easy prey. Unfortunately, wings can't suddenly develop and start flying when enemies appear.

The Dutch explorer Abel Tasman passed by the islands in 1642 and named them New Zealand. But the Maori were sole proprietors over the land of the moa until 1769, when Captain Cook landed there. The first European had arrived, and the Maori were forced to make room for white settlers who would follow. The natives described moas and moa hunts, but fact was diluted with legend. Then, in 1838 Dr. John Rule obtained a battered thighbone of a huge creature. He brought it to England to Sir Richard Owen, the leading authority on animal anatomy. Owen dismissed it as an ordinary soupbone at first but, after comparing it with an ostrich skeleton, recognized it as a thighbone of an impressively large bird. In 1839 Owen reported the bird to the Zoological Society of London and gave the moa its first official scientific recognition. He gave the moa the generic name of Dinornis ("terrible bird"), believing it to be at least as large as an ostrich. After several cases of moa bones were sent to him for examination, he had plenty of bones to reconstruct entire specimens.

Zoologists today classify the moa into five genera and at least 24 species. The smallest moa was about the size of a turkey, and the tallest, the 12—foot Dinornis maximus, which must have weighed at least 600 pounds, was twice the height of a man. Many bones and other remains identify the moa as a massive, ostrichlike bird with a long neck, sturdy legs, and hairlike feathers similar to the kiwi's. Footprints show three large toes with heavy claws spanning 14 inches and a stride of over 30 inches. No moa remains show traces of wing bones, so ancestral moas must have lost the power of flight millions of years ago. Radiometric dating of a fossilized moa bone gave an age of 35 million years, clearly demonstrating the antiquity of this genus in New Zealand.

In 1939 two scientists discovered a sticky, muddy swamp that had been a natural trap for moas. The heavy birds venturing onto the deceptive crust became mired in the clay and couldn't get free. Complete skeletons were found standing upright, buried in the quicksandlike deposits. They proved that Owen's deductions based on the single thigh fragment were quite accurate. The largest species of moa found here was about 12 feet tall and weighed close to half a ton. Carbon—14 dating showed that the swamp had developed about 1700 b.c. Another radiometric date showed that the largest moas were still being trapped in the swamp as recently as 675 years ago. By this time the birds' biggest headache had already arrived, because now they had become important food for humans.

To zoologists the most important characteristic of the giant moas was the fact that the skull of a 12—foot moa was no larger than a poodle's. Compared with its immense body the skull was insignificant, a microcephalic pinhead perched atop a long, graceful, tapering neck. The moa's adaptations are well known, for several specimens have been found with eggs, some containing unborn chicks. A few skeletons still have pieces of skin adhering to the bones, and there are also vestiges of feathers, footprints, and (most important of all) gizzard linings.

The moa had to eat continuously to supply fuel for so large a body. With such a small head and no teeth to chew with, though, it first had to solve the problem of how to grind its food down to proper size for digestion. As with its ostrich cousin, and other seed— and grain—eating birds, the moa swallowed a number of pebble—sized stones that were retained in its gizzard. They very efficiently pulverized the vegetation swallowed by the puny—headed moa. With a way of chewing internally, moas didn't need teeth.

Most of the stones associated with moa skeletons were types found nowhere else in the entombing sediment. For miles around the sites of moa remains scientists searched for the original source of country rock containing the type of stone the gizzards contained. Searchers found that the birds had often traveled over 10 miles to acquire the right pebbles. Such careful selection suggests that the moas were driven to find the hardest possible rocks for their gizzards. Undoubtedly, long, energy—expending searches were involved, implying that very special rocks were essential to process enough food to support their metabolism. Moa gizzard stones are highly polished and glisten with a fine patina achieved by almost continuous grinding of the hard pebbles against each other. Only the pulverizing of great masses of leaves and twigs could satisfy the food requirements of the moa.

For millions of years before humans arrived the moa had reproduced itself adequately, probably laying one or two eggs per season. In the absence of predators, reproduction was controlled appropriately by nature. When the Great Fleet of the Maori arrived, the moa were abundantly distributed throughout the two islands. New Zealand must have seemed a land of plenty to the ancestral Maori, with its cornucopia of juicy, flightless birds. But the moas' slow rate of reproduction helped cause their extinction, because they couldn't keep up with the human demand for eggs and birds as a basic food supply. Between a.d. 1300 and 1800 they were exterminated by the Maori. Probably most were gone by 1500, with only a few remote stragglers lingering into the next century or two.

All Maori archaeological sites show an abundance of moa bones. The oldest sites contain the greatest profusion of moa eggs and remains. Scientists know that the natives ate the flesh and eggs, adorned their hair with the feathers, made fishhooks from bones, and crushed the skulls and tattooed themselves with the powder. Mounds and cooking pits often contained the remnants of a huge moa feast. Their importance to the Maori was revealed in the discovery of a tomb containing a human skeleton in a sitting position. In the skeleton's hand was an entire Dinornis egg, 10 inches long, apparently placed there for nourishment during the journey to the next world.

Early white settlers described the method of hunting. Hunters would surround the moa, which when attacked would stand on one leg and kick with the other. Several hunters would keep the moa's attention while another sneaked up from behind with a heavy club and hit the leg that supported the bird. As it went down they would finish it with spears. The hunts often had unplanned results. At times the agile moa, sensing the man sneaking up on it from behind, would turn on the skulking human with a powerful kick that quickly ended the hunter's earthly problems. Sometimes, instead of kicking, the bird towering over the hunter would come down with a powerful swipe of its neck, toppling the hunter. When a death occurred the surviving hunters pursued the killer bird with a vengeance and never let up until the moa was captured. The family of the dead man was usually awarded the choice pieces of the bird during the meal that followed.

After 1500, as the moa became increasingly scarce the Maori began to look around for other forms of meat. The only animals large enough to feed them were other human beings. Cannibalism became the logical solution. Once it began, a permanent state of war existed between all the tribes. Archeological sites from a.d. 1500 to 1800 showed fewer and fewer moa bones and more and more human ones. Warfare became a sacred institution, often followed by ritual feasting: leading warriors consumed the heart, and the hunters gained courage by drinking blood. Cannibalism continued almost completely unchecked well into the 19th century.

Smaller species of moa may have survived into the mid—19th century. Stories of moa hunts were still told, but information was from recollected memories. One of the last was told in 1868 to Sir George Grey, the governor of New Zealand, when he met a party of Maori hunters. They enthusiastically told him of their recent successful hunt, the killing of a small moa. According to the governor, "they described it with so much spirit" he believed they were telling the truth. If so, they may have had the dubious honor of killing the last of the moas.