New species splits recognized by the American Ornithologists Union

Another traditional midsummer event is the unveiling of the new decisions made by the American Ornithologists Union regarding the species of North American birds.  Each year, new information is examined and decisions are made about whether some species are best considered two species (or three or four), and whether the present order and arrangement of species makes sense any more.  So every July, birders look to the latest AOU checklist supplement to see what the news is, since that news will affect the names they see in future field guides, the order of those field guides and checklists around the continent, and of course the length of their life lists.

So here are the news–in edited form…

1.  The Black Scoter of North America is recognized as separate from the Eurasian species, and is now called the American Scoter (I’m still waiting for them to call some species “Canadian…”). [late-breaking news–apparently the AOU made an error with the scoter names and will correct it in the next issue of their journal, the Auk.  They meant to name the North American birds the Black Scoter and the Eurasian birds the Common Scoter.  This retains the names already in use on either side of the Atlantic].

2.  The Whip-poor-will is split into two species, the Eastern Whip-poor-will of eastern North America, and the Mexican Whip-poor-will, which breeds in the mountains of southwestern USA and down into Mexico.  The species have different calls (the Mexican one talks faster) and differ significantly in genetics, as well as having subtle plumage differences.

3.  The Winter Wren is split into three species;  the Pacific Wren west of the Rockies, the Winter Wren east of the Rockies, and the Eurasian Wren (known in Britain as THE wren) in Eurasia.  This is based on a number of studies, including genetic work done in northeastern BC (near Tumbler Ridge) by Dave Toews and Darren Irwin that showed the two species didn’t breed with each other, had different songs, and looked different as well.  There’s a thorough discussion of all this research on Slybird’s blog.

4.  The Greater Shearwater is now called the Great Shearwater to match up with the name used elsewhere in the world.

5.  For those of you who have birded in Hawaii, the Elepaio has been split into three species, one for each of the islands it is found on:  Kauai, Oahu and Hawaii.

There are many other changes, mostly regarding the scientific names of birds (e.g. the waterthrushes are now in the genus Parkesia, separated from the genus Seiurus now used only for the Ovenbird), new families (e.g. longspurs and Snow Buntings are now in their own family, the Calcariidae) and the order of species (e.g. the herons and ibises are now considered more closely related to pelicans than to storks, so are moved from the stork Order Ciconiiformes to the pelican Order Pelecaniformes; and the cormorants, boobies and gannets are moved out of the Pelecaniformes into their own order, Suliformes, as are the tropicbirds moved into the Phaetontiformes).

You can get all the details by reading the full checklist supplement online.