Saturday, 16 February 2013

Extinct species #1; Canary Island Black Oystercatcher.

Canary Islands Black Oystercatcher, Haematopus meadewaldoi.

Formally considered a subspecies of African Oystercatcher H. moquini which in turn has also been considered a subspecies of Eurasian Oystercatcher H. ostralegus. Split from African Oystercatcher by Hockey (1982).

History: By the mid nineteenth century it was already considered 'not frequent'. The last definite record was this specimen shown here which was shot in 1913 although locals thought the species hung on until around 1940. There have been further unsubstantiated sightings on Tenerife.

Specimen number 1939.12.9.25. Collected on Graciosa Island 03/06/1913:
Left lateral view. 

More intriguingly there is a record of three black oystercatchers seen on the Senegal coast in 1970 and 1975 although it is not known which species was involved. This could have referred to Canary Island Oystercatchers that moved to the mainland as had earlier been suggested or they may have been African Oystercatchers. The problem with the latter species is that it has not otherwise been recorded north of Angola. Another possibility is that they were simply melanistic Eurasian Oystercatchers.


Specimen number 1939.12.9.25: dorsal view.
Searches have failed to find any further trace of the species in the Canary Islands.

Specimen number 1939.12.9.25: ventral view.
Extinction: Officially pronounced extinct on the IUCN red data list in 1994. Last specimen 1913. There are only four known specimens in existence.

Probably became extinct as a result of habitat loss due to human activity.

Probable major cause was invertebrate collection on rocky shores which will have disturbed them both during breeding and feeding. Eggs and birds known to have been taken for food. Cats and rats also suspected to have hastened decline.


Specimen number 1939.12.9.25: upper left 45° angle view

References:

del Hoyo, J., Elliott, A. & Sargatal. J. eds (1996) Handbook of the birds of the world. Vol. 3. Hoatzin to Auks. Lynx Edicions, Barcelona.

Birdlife International (2013) Species factsheet: Haematopus meadewaldoi.
http://www.birdlife.org/datazone/speciesfactsheet.php?id=3089 Downloaded from http://birdlife.org on 14/02/2013.

Wikipedia 14/02/2013: http://en.wikipedia.org/wiki/Canarian_Oystercatcher

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