Proposal (690) to South American Classification Committee

 

 

Transfer Crex crex from Hypothetical List to Main List

 

Effect on South American CL: This transfers a species from our Hypothetical List to the Main List.

 

Background: The species account in the Hypothetical List is as follows:

 

Photographed on Fernando de Noronha, Brazil, 28 November 2012 (Burgos and Olmos 2013).  SACC proposal badly needed.”

 

From Kleber de Burgos, http://www.burgos.com.br/]:

 

“[On 28 November 2012, noticed a bird walking fast, but without trying to fly, from the plant-covered reservoir [Aćude do Xaréu, Fernando Noronha 03°51’60”S; 32°25’42”W] to the surrounding forest and scrub about 15 m from his position. Realizing it was a rail, [Kleber] quickly made a sequence of nine digital photographs [three of these images are available in the article] before the bird disappeared into the vegetation.”

 

Fernando de Noronha has previously attracted several Palaearctic and African vagrants (e.g. Silva e Silva & Olmos 2006). Crex crex now joins this interesting group.  Despite C. crex being a long-distance migrant, Fernando de Noronha lies close to commercial shipping routes, so the possibility of this bird being ship-assisted for all or part of its journey cannot be excluded.

 

The original paper of Burgos & Olmos (2013) is available at:

http://goo.gl/ight3I

 

The best photo of Noronhaęs Corn Crake record is at:

http://www.wikiaves.com/1174069

 

The existence of recent and almost regular records of Crex crex in Iceland, the Azores, Newfoundland, and Labrador (also a photo from 2003 from Guadeloupe, Se. Caribbean) indicates a recurring movement pattern westward from Europe (Howell et al. 2012, p. 207).

 

Because some records from North America are not considered to ship-assisted (Howell et al. 2012, p. 23), I see no reason to treat the trans-Atlantic individual at Fernando de Noronha any differently.

 

Literature Cited:

 

Burgos, K. & Olmos, F. 2013. First record of Corncrake Crex crex (Rallidae) for South America. Revista Brasileira de Ornitologia, 21: 205-208.

Howell, S. N. G., Lewington, I., and Russell, W. 2014. Rare Birds of North America. Princeton University Press.

Silva e Silva, R. & Olmos, F. 2006. Noteworthy bird records from Fernando de Noronha, northeastern Brazil. Revista Brasileira de Ornitologia, 14: 470-473.

 

J. F. Pacheco, November 2015

 

 

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Comments from Remsen: “YES.  This meets all criteria for inclusion in Main List.  As for the problem of ship-assistance, I suspect a large percentage of all trans-oceanic vagrants spend at least some time resting on ships (as do many landbirds crossing large expanses of water), and there is no way to determine which have and have not. I regard that as irrelevant anyway because natural floating debris and Sargassum has probably been used by birds migrating over oceans “forever”; ships differ in that they are larger and sturdier but otherwise function in a similar way.  What counts is evidence of restraint on a ship, i.e. humans capturing and restraining a migrating bird, and then transporting it to a destination not on the bird’s itinerary.”

 

Comments from Stiles: “YES – the photos are decisive, especially as there is no indication of previous restraint (cage wear of flight feathers, etc.).”

 

Comments from Zimmer: “YES.  The photos supporting this record are conclusive as regards the identification, there is an established pattern of long-distance vagrancy, and there is no evidence of prior restraint of this individual bird.  I would add that Van’s comments regarding the “problem of ship-assistance” are spot-on in my estimation – in cases like this, there is no way of knowing if the bird hitchhiked or not, and even if it did, we are talking about a natural behavior – it’s what birds lost at sea do.”

 

Comments from Robbins: “YES, for adding Crex crex to the accepted list because the photos make that component unequivocal.  As has been pointed out, we’ll never know how the bird got there.”

 

Comments from Jaramillo: “YES – Identification is sound based on photos and publication. Do we have a policy on ship assistance of a wild and unrestrained bird?”