Australasian Swamphen

Australasian swamphen are long-legged birds, standing about 51 cm tall, with dark plumage, black upper-parts, and a contrasting white undertail. They have a large, bright red bill and an expanded frontal shield that extends from their culmen, giving them a distinctive appearance. Their throat and breast are purple, contributing to their striking colour pattern. Variations exist across subspecies, with some having greener or bluer upper-parts or smaller body sizes depending on the region. The New Zealand population (along with green-yellow swamphens in Tasmania) are possibly slightly larger than mainland Australian birds, but are otherwise identical.

The Australasian swamphen occurs in mainland Australia, eastern Indonesia, the Moluccas, Aru and Kai Islands, and in Papua New Guinea. It is also found on New Zealand's main islands and in the Chatham and Kermadec Islands.

Dispersal. Although it is thought that P. porphyrio subspecies rarely use flight, this lineage has effectively dispersed, colonised, and established populations numerous times across extensive bodies of water. In support of the belief that Australasian swamphens are good flyers, and may have self-introduced, a dead bird was found on L'Esperance Rock, a tiny, isolated rock in the Kermadec group of New Zealand, more than 200 km from the nearest established population. This demonstrates the ability of swamphens to fly great distances over the sea.

Subspecies. The Australasian swamphen has five subspecies distributed as follows:

P. m. melanopterus – northern and south-eastern Sulawesi, the Moluccas, Lesser Sundas and New Guinea region. P. m. pelewensis – Palau (western Caroline Islands, western Micronesia). P. m. melanotus – northern and eastern Australia, Tasmania, Lord Howe and Norfolk Islands, as well as the North, South, Stewart, Kermadec and Chatham Islands of New Zealand. P. m. bellus – far south-west Australia. P. m. samoensis – Admiralty Islands to New Caledonia, Solomon Islands, Fiji and Samoa.

In New Zealand. …

Swamphens exhibit diverse feeding and foraging habits, making use of both plant and animal resources in their diet. Primarily, they consume plant material, including stems, shoots, leaves, and seeds of various grasses, sedges, rushes, and clover. However, they are also opportunistic feeders, supplementing their diet with animal matter, primarily invertebrates. Notably, they have been observed preying on larger vertebrate species, such as pied stilt eggs, Eurasian blackbird chicks, and pāteke and mallard ducklings in New Zealand, as well as common starlings, myna chicks, black swan eggs and cygnets in Australia. This positions them as both a predator and prey species within their ecosystems. Their foraging habits extend beyond natural environments, often leading them to forage on roadsides, where they seek out invertebrates struck by vehicles and graze on grass shoots from mown verges. In these areas, they also ingest grit, which aids in processing food in their gizzards. Swamphens are bold foragers and have a history of raiding gardens for crops such as kumara and taro, a behaviour that has continued as they adapted to European farmland by feeding on grain and vegetable crops. …