Friday

New Zealand Birds- Weka

This will begin a series on the birds of New Zealand.
The Weka(
Gallirallus australis) is a member of the rail family and native only to New Zealand (NZ). It has four subspecies all of which are considered vulnerable by the IUCN. Efforts to reintroduce the Weka to its original habitats have been moderately successful. Some subspecies have been successfully reintroduced while others have continued to decline in numbers. The total population is estimated at 120,000- 187,000 birds. The current threats to the Weka are feral cats and dogs which prey on the adults. The chicks face threats from stoats and rats which eat both eggs and chicks. Other threats include introduced plant species out competing their native food plants as well as pressure from introduces browsers eating their food resources.
In historic times before Europeans arrived on NZ the Weka were both revered and hunted by the Maori who saw them as curious and feisty, but these traits also made them easy to catch. They were used for their feathers, their fat was used to treat inflammation, and they were eaten for food.
The Weka, like many birds in NZ, is flightless. This loss of an evolutionary novelty most likely came about because for over 60 million years there were no mammals on NZ which would prey on these birds. Because of this their only predators were other birds which could be hidden from through the use of camouflage which the Weka accomplishes well with its brown feathers. Like all rails it has large un-webbed feet for walking across reeds in marshes. The Weka can be found in a wide range of habitats from sub-alpine to coastal wetlands to urban areas. They are omnivores with plants making up 70% of their diet and small invertebrates making up the other 30%. Their ability to live in many habitats and eat many things has probably served them well in their ever changing world. Other flightless birds on the island have not survived as well as the Weka.

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