Chatham duck

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Chatham duck
Systematics
Order : Goose birds (Anseriformes)
Family : Duck birds (Anatidae)
Subfamily : Anatinae
Tribe : Swimming ducks (anatini)
Genre : Pachyanas
Type : Chatham duck
Scientific name of the  genus
Pachyanas
Oliver , 1955
Scientific name of the  species
Pachyanas chathamica
Oliver , 1955

The Chatham duck ( Pachyanas chathamica ) is an extinct species of duck that was endemic to the Chatham Islands . It is known only from subfossil bone material found in the Te Whanga Lagoon .

The skeleton identifies the Chatham duck as a large, sturdy duck. With a weight of 1.5 kilograms, it weighed about as much as the recent Paradise Kasarka ( Tadorna variegata ). Her short wings suggest she was probably flightless. It had large salt glands on its skull, which could indicate that its habitat was the brackish waters of the Te Whanga Lagoon and sheltered sections of the coast.

The family relationships of the Chatham duck have long been unclear. Skeletal features, such as the protruding rear edge of the shoulder blade (Margo caudalis) and a raised dorsal hump on the humerus, indicate a relationship with the half-geese (Tadorninae) than with the swimming ducks (Anatini). However, the beak has similarities with a swimming duck's beak. Investigations of the mitochondrial DNA place the Chatham duck in the genus Anas as a basal species within a clade of New Zealand and sub-Antarctic ducks ( Auckland duck ( A. aucklandica ), New Zealand duck ( A. chlorotis ) and Campbell's duck ( A. nesiotis )).

The Chatham duck found its main food, which probably consisted of crabs and shellfish , on the surface of the water. It may also feed on aquatic plants. In addition to the Hawkins rail ( Diaphorapteryx hawkinsi ), the Chatham duck is the second endemic water bird species from a monotypical genus that has become extinct on the Chatham Islands.

The exact time of the extinction is unknown. It apparently disappeared between the arrival of the Polynesians in 1350 and the arrival of the Europeans in 1791. Since the Pacific rat could only be dangerous to the chicks, overhunting by the Polynesian settlers is the most likely cause of extinction.

literature

  • A. Tennyson and P. Martinson: Extinct birds of New Zealand. Te Papa Press, 2006, ISBN 0-909010-21-8
  • Trevor H. Worthy , Richard N. Holdaway: The Lost World of the Moa. Prehistoric Life of New Zealand. Indiana University Press, Bloomington 2002, ISBN 0-253-34034-9 .

Individual evidence

  1. ↑ Mitchell, Kieren J .; Wood, Jamie R .; Scofield, R. Paul; Llamas, Bastien; Cooper, Alan (2014). Ancient mitochondrial genome reveals unsuspected taxonomic affinity of the extinct Chatham duck (Pachyanas chathamica) and resolves divergence times for New Zealand and sub-Antarctic brown teals . Molecular Phylogenetics and Evolution 70: 420-428. doi: 10.1016 / j.ympev.2013.08.017

Web links

  • Illustration from A. Tennyson and P. Martinson: Extinct birds of New Zealand. On-line