Tag Archives: Anas acuta

Anas acuta ssp. modesta Tristram

Sydney Island Pintail (Anas acuta ssp. modesta 

The Northern Pintail (Anas acuta L.) is a holarctic species, which inhabits the whole north of Europe, Asia and North America, as a migrating bird this species can appear almost everywhere, including the remotest islands in the middle of the Pacific Ocean.  

The imagination, that, in this way, some of these birds may colonise new and suitable-appearing regions is compelling – and in no way unreasonable.  

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The form, discussed here, nearly unknown, and probably invalid by the way, is known only on the basis of three specimens (a male and two females), which were collected on the island of Manra (formerly Sydney Island) in the Phoenix group of Kiribati.  

This may have been resident birds, or rather nothing but wintering Northern Pintails in subadult plumage, the author of this form, H. B. Tristram, contemplated about them (On an apparently new Species of Duck (Dafila) from the Central Pacific).:  

The only note I have respecting it is, that there were no Ducks on the island on Mr. Arundel’s arrival, but that afterwards they appeared, and were tolerably numerous for a time. I gather from this remark that it is probably a migrant from one island to another, and a glance at the position of Sidney Island on the map will show that a Duck may enjoy a considerable range of migration in those regions, without necessarily coming under the eye of a collector.”  

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However, see also David W. Steadman (Extinction and Biogeography of Tropical Pacific Birds).:  

… Other resident ducks, currently unknown, probably have been lost since human arrival. Perhaps the northern pintail Anas acuta, with more migrant records in Oceania than any other temperate species of duck … developed resident populations on some remote islands. …”  

So, as mentioned before, this form is perhaps invalid respectively identical with the nominate race – but it shall be mentioned here for the sake of completeness, and not least as a kind of anticipation for all prospectively to be discovered, extinct duck forms, which certainly have existed on many islands of the Pacific Ocean.  

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References:  

[1] H. B. Tristram: On an apparently new Species of Duck (Dafila) from the Central Pacific. Proceedings of the Zoological Society of London 79-80. 1886 
[2] David W. Steadman: Extinction and Biogeography of Tropical Pacific Birds. University of Chicago Press 2006  

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Depiction from: ‘H. B. Tristram: On an apparently new Species of Duck (Dafila) from the Central Pacific. Proceedings of the Zoological Society of London 79-80. 1886’ 

(public domain)

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edited: 17.10.2020