Giant Moa

• GeneralIt stood 3.6 m tall and died out some 100 years after the Māori arrived.
• It belongs to the only bird group known with no trace of a wing at all: the moas did not even have the reduced wing bones that ostriches and emus retain.
• Its disappearance was sudden: the nine moa species are reckoned to have gone extinct in less than two hundred years after the human arrival in New Zealand, one of the fastest documented extinctions of any megafauna.
• Almost all birds reach adult size in under a year; the moa took close to a decade to attain skeletal maturity. That life strategy, workable on islands with no land predators, became lethal when the first Polynesian settlers arrived around 1280-1300, and it is regarded as one of the causes of its rapid disappearance. It also showed extreme reversed sexual dimorphism: the females reached 2 m at the back and around 200 kg in average weight, and the males barely a third of that.

Skeleton type

Vertebrate - internal bony skeleton (bird)

Habitat and environment

Forest, scrub and subalpine grassland of the South Island of New Zealand

Sexual maturity

Close to ten years to reach skeletal maturity, a juvenile development with no equivalent among living birds

Litter / clutch size

1 egg

Sources consulted: IUCN Red List · Animal Diversity Web · Wikipedia (es)