Proposal
(509) to
South
Transfer Chlidonias
leucopterus from Hypothetical List to Main List
Effect on the SACC List: This
transfers a species from the Hypothetical List to the Main List.
Background: The
Hypothetical List currently reads:
Chlidonias
leucopterus White-winged Tern: Published photo from Rio Grande
do Sul, Brazil (Aldabe et al. 2010).
Aldabe et al.’s abstract
reads: “On 20 November 2008 a single White-winged Black Tern Chlidonias
leucopterus in complete breeding (alternate) plumage was recorded in
Lagoa do Peixe National Park, Rio Grande do Sul, southern Brazil. The
bird was photographed showing the diagnostic black underwing coverts. It is
suspected that it was an occasional visitor. This is the first record for
Brazil and South America.”
Photographic evidence: Two
photographs are reproduced in the publication (just email Van Remsen if you
need a pdf). They clearly show the diagnostic pure white upperwing-coverts,
diagnostic white rump contrasting with a black head, throat, and breast,
together with diagnostic black underwing-coverts.
Recommendation: There can
be no doubt about the identification, there seems to be no controversy over the
authenticity of the locality data. The only anomaly is that the first author
did not see the bird. I recommend a YES vote to add this species to the main
list as a vagrant to the region.
Literature
Cited:
Aldabe, J.,
Rocchi, A. & Mondón, G. 2010. Primer
registro de Chlidonias leucopterus (Charadriiformes: Sternidae) para
Brasil y Sudamérica. Rev. Bras. Orn. 18(3): 261-262.
Mark Pearman, October 2011
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Comments from Pacheco:
“YES. O CBRO acompanhou com interesse a divulgação e
confirma as qualidades do registro.”
Comments from Pérez: “YES. Evidence is clear and is supported by the
Brazilian Ornithological Records Committee, as stated by Fernando.”
Comments from Jaramillo:
“YES. Looked at the photo and it appears
undeniably to be that of C. leucopterus. This one was overdue for South
America as well!”
Comments from Zimmer:
“YES. The published photograph from
Lagoa do Peixe leaves no doubt as to the identification, and this is
a likely locale for such a bird to turn up.”