AOU 53rd Supplement

It's that time of year again when the AOU's Committee on Classification and Nomenclature - North and Middle America publishes its supplement to the Check-list of North American Birds. These guys just love to mix it up, doggedly pursuing the chimera of a perfect taxonomy.



This year's supplement lacks some of the pizazz of last year's reorganization of the wood warblers. On the other hand, the rearrangement of the Falconiformes (caracaras & falcons) and Psittaciforms (parrots) to a position immediately before the Passeriformes is intriguing. This is consistent with the thesis that there are two independently evolved lineages of raptor, rather than one as is traditionally believed. Also, there is the exciting addition Bryan's Shearwater; the first newly described (rather than merely split) North American species in recent memory.

The most relevant change for Ontario domestic birders is probably the change of genus for Purple, Cassin's and House Finch.

An editorial criticism I have is the committee's use of the term "resurrect". A more objective choice of terminology would be "reinstate".


A "typical" Savannah Sparrow exhibiting obvious dissatisfaction
with the committee's failure to recognize its distinctness from its
"Large-billed", "San Benito" or "Belding's" conspecifics.

One item that was not approved for this year's supplement was the proposal to modify the species-level taxonomy of the Savannah Sparrow by recognizing up to four separate species. We have seen variations of this proposal before, but for various reasons the committee has so far declined to split this species. I must admit, I was kind of rooting for committee member (and U of T prof) James Rising on this one, but it was not to be.