The bush moa, Anomalopteryx didiformis, was an extinct species of flightless bird native to New Zealand. It was one of the smaller moa species within the Dinornithidae family, having evolved in isolation for millions of years.
Physical Description and Behavior
The bush moa was a modestly sized bird, standing approximately 1.3 meters (51 inches) tall, comparable to a large turkey. Its stout body was supported by powerful legs, adapted for ground dwelling. The bird’s entire body, including its head and neck, was covered in thick, woolly feathers, which were likely reddish-brown on its back and a lighter, buff color underneath.
Fossil evidence, including a partially mummified skeleton, provides insights into its appearance. It possessed a short, sharp-edged beak, suitable for cutting and clipping tough plant material. Robust leg bones indicated a slow-moving, ground-dwelling existence.
Ecological Niche
The bush moa primarily inhabited the dense lowland forests and shrublands of New Zealand, found across both the North Island and specific areas of the South Island. Its diet consisted of various plant materials, including leaves, twigs, fruits, and seeds.
Scientists deduced its diet through fossilized gizzard contents and coprolites. These remains often contain gastroliths, or gizzard stones, which helped grind tough, fibrous plant matter into digestible pulp. This specialized diet and habitat preference positioned the bush moa as a forest specialist within New Zealand’s ecosystem.
The Path to Extinction
The bush moa, like all other moa species, became extinct rapidly after Polynesian settlers arrived in New Zealand around the late 13th century. This period marked a dramatic shift for New Zealand’s native wildlife, which had evolved in an environment largely free of mammalian predators. The primary cause of the bush moa’s disappearance was overhunting by these human settlers.
Its flightless nature, slow movement, and lack of defenses made it an easy target. Archaeological evidence from midden sites indicates moa were a staple food source for early Polynesians. Beyond direct hunting, habitat destruction also played a role as forests were cleared for settlement and agriculture, reducing the available territory and food sources for the birds. The introduction of Polynesian dogs (kuri) further contributed to their decline by preying on adult moa and their vulnerable chicks. The extinction of all moa species occurred within a century or two of human arrival, likely by around 1425 CE.