[Peter C.]

Discussion thread for Black Tern. If you would like to add a comment, click the Post Reply button.

In another thread, I have seen a posting suggesting that the division between C. n. surinamensis ("American Black Tern") and C.n. niger ("Black Tern") has been upped to the species-level. Is there any basis for this?

[Richard Klim]

Originally Posted by Peter C.

In another thread, I have seen a posting suggesting that the division between C. n. surinamensis ("American Black Tern") and C.n. niger ("Black Tern") has been upped to the species-level. Is there any basis for this?

Hallam, N. & Lewington, I. 2009. Identification of American Black Tern. Birding World 22(9): 383-388:

"The Palearctic and Nearctic forms of Black Tern are currently regarded by the BOU and AOU as one species comprising two subspecies, C. n. niger and C. n. surinamensis. Both taxa are separable in the field in all plumages. Their breeding and wintering grounds do not overlap (so there is no interbreeding) and they also have slightly different moult timings. The criteria required to signify species status (Helbig et al. 2000) therefore appear to be satisfied and thus elevation to species rank appears to be amply justified.

Eds: As suggested by the authors, the splitting of surinamensis and niger seems overdue. In line with current evaluation, and the unambiguity of its identification in all plumages, Birding World will henceforth treat these forms as separate species, Black Tern Chlidonias niger and American Black Tern Chlidonias surinamensis."

Richard

[Steve Lister]

It's bad enough when different taxonomic committees treat birds differently but here we have two of the world's most authoritative bodies agreeing (for the moment) so a magazine that disagrees makes their own decision.

Time to save £50 or so a year I think.

Steve