Auckland Teal (Anas aucklandica)

Auckland Teal

[order] ANSERIFORMES | [family] Anatidae | [latin] Anas aucklandica | [authority] Gray, 1844 | [UK] Auckland Teal | [FR] Sarcelle brune | [DE] Aucklandente | [ES] Cerceta Maori | [NL] Aucklandtaling

Subspecies

Genus Species subspecies Region Range
Anas aucklandica AU Auckland Islands

Genus

Anas is a genus of dabbling ducks. It includes mallards, wigeons, teals, pintails and shovelers in a number of subgenera. Some authorities prefer to elevate the subgenera to genus rank.[1] Indeed, as the moa-nalos are very close to this clade and may have evolved later than some of these lineages, it is rather the absence of a thorough review than lack of necessity that this genus is rather over-lumped. The phylogeny of this genus is one of the most confounded ones of all living birds. Research is hampered by the fact the radiation of the two major groups of Anas ? the teals and mallard groups ? took place in a very short time and fairly recently, roughly in the mid-late Pleistocene. Furthermore, hybridization may have long played a major role in Anas evolution, with within-subgenus hybrids regularly and between-subgenus hybrids not infrequently being fully fertile.[1] The relationships between species are much obscured by this fact, and mtDNA sequence data is of dubious value in resolving their relationships; on the other hand, nuclear DNA sequences evolve too slowly to resolve the phylogeny of the subgenus Anas for example. Some major clades can be discerned. For example, that the traditional subgenus Anas, the mallard group, forms a monophyletic (in the loose sense, i.e. non-holophyletic) group has never been seriously questioned by modern science and is as good as confirmed (but see below). On the other hand, the phylogeny of the teals is very confusing. For these reasons, the dabbling duck lineages more distantly related to mallard group (which includes the type species of Anas) than the wigeons should arguably be separated in their own genera. These would include the Baikal Teal, the Garganey, the spotted black-capped Punanetta group, and the shovelers and other blue-winged species. Whether the wigeons, which are very distinct in morphology and behavior, but much less so in mtDNA cytochrome b and NADH dehydrogenase subunit 2 sequences, should also be considered a distinct genus Mareca (including the Gadwall and Falcated Duck) is essentially the one remaining point of dispute as regards the question which taxa should remain in this genus and which ones should not.

Physical charateristics

Uniform dark brown face, fine white ring around eye; body dark brown with pale edges to feathers, breast chestnut; bill bluish black, legs and feet slate grey; breeding male ducks glossy green hats of plumage on the head with distinctive distinguished-looking narrow white collars, white patches on flanks.


wingspan min.: 130 cm wingspan max.: 150 cm
size min.: 48 cm size max.: 53 cm
incubation min.: 30 days incubation max.: 33 days
fledging min.: 60 days fledging max.: 70 days
broods: 1   eggs min.: 3  
      eggs max.: 4  

Range

Australasia : Auckland Islands. Anas aucklandica is endemic to New Zealand where it has permanent populations on Ewing, Enderby, Rose, Ocean, Adams, Disappointment and Dundas Islands in the Auckland Islands group.

Habitat

It primarily inhabits sheltered coastlines feeding on tideline resources, and uses dense coastal vegetation as escape and nesting cover. Pairs may retreat 100-200 m up small streams or to coastal pools for daytime cover, but forage on the shorelines after dark

Reproduction

The breeding rate and annual productivity is low, with clutches of 3 to 4 eggs laid from late October, with the first broods appearing in December. The incubation period is about a month in the wild, with incubation performed by the female alone. The male remains close and guards the female and feeds during nest relief. Both parents attend to and defend their young throughout the fledging period of 60 to 70 days.

Feeding habits

It feeds mostly in washed up seaweed for invertebrates, or in coastal pools, and also eats algae

Video Auckland Teal

httpv://www.youtube.com/watch?v=_zcYFa_KYBA

copyright: Brooke Clibbon


Conservation

This species is classified as Vulnerable because it has a very small population. The possibility of accidental introductions of invasive mammal species to the islands is a continuing concern, although the species occurs at enough locations to be relatively secure in the short term.
The total area of the seven islands is 113 km2 but, with the exception of Disappointment Island, birds were predominantly dispersed along island shorelines, but now occur throughout Adams Island at least. It formerly bred on Auckland Island itself, where there are records from the 1940s. Three population estimates suggest that total numbers do not exceed 600 individuals, three indicate numbers of more than 1,000, and one suggests a population of more than 2,000 birds. The population appears to be stable. Introduced cats and pigs caused its extinction on Auckland Island. The accidental introduction of mammals to the remaining island populations could cause further local extinctions but it is unlikely to affect all sub-populations simultaneously. The introduction of avian disease is also considered a significant potential threat.
Auckland Teal status Vulnerable

Migration

Sedentary

Distribution map

Auckland Teal distribution range map

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