Wednesday, July 27, 2011

New AOU Checklist Supplement!

It's that time of year again, when the American Ornithologists' Union North American checklist committee has gotten together and made some changes to the "official" checklist of North American birds - adding new species, recognizing splits, reorganizing families, changing names, and all that good stuff.  They don't always make good decisions, but it's always interesting to see where recent research in taxonomy has taken us.

The new supplement to the checklist is available in its entirety here, and you can even read the specific proposals here.  Or you can read this blog post to see what's been changed!  Be sure to stick around until the end, because the thorough reshuffling of the wood-warblers has got to be the most interesting thing to come out of this one.

I'm only outlining the more major points here (especially - but not entirely - the ones relevant to ABA-area birders), so if you're really interested in the nitty-gritty, be sure to check out the published proposal.

1. Species Added
Species are added when a new vagrant occurs in the AOU area, when existing species are split, or when the AOU recognizes an exotic as having a self-sustaining, established population.  These birds have been newly recorded in North America:
- Tahiti Petrel
- White-chinned Petrel
- Long-winged Harrier
- Gray-bellied Hawk
- Solitary Snipe
- Large-billed Seed-Finch

2. Name Changes
Sometimes what we see as name changes are really the results of splits, for example, with old-world birds.  Other times they're changes.  The name change from our beloved Common Moorhen to Common Gallinule is the result of a split with the old world Common Moorhen (neither of which, incidentally, are actually found on moors).

3. Just Splits and Lumps
If there is no name change resulting from a split or lump (say, with an old world species), it's likely to go unnoticed.  In other cases, North American birders may gain or lose a species on their life lists.
- Snowy Plover is split from the widespread old world Kentish Plover
- Chestnut-mandibled Toucan is considered a subspecies of Black-mandibled Toucan
- Mexican Jay has been split.  The birds in Arizona are still called Mexican Jay, while the birds farther south in Mexico have gained the awesome name Transvolcanic Jay

4. Taxonomic Reshuffling
Splits and lumps don't just happen at the species level!  Ornithologists learn new things all the time about the familial affinities of certain birds, where they belong in the grand scheme of things.  Based on some of this research, the AOU recognizes:
- Sandgrouse get their own order, Pteroclidiformes
- Sapayoa gets its own family, Sapayoidae
- Tityras, Becards, Schiffornis, and some Mourners are placed in the a new family, Tityridae (wait, we already knew that)
- Bluethroat, rubythroats, bluetails, wheatears, and Stonechat are moved from Turdidae (thrushes) to Muscicapidae (Old World Flycatchers)
- Bush-tanagers are moved from Thraupidae (tanagers) to Emberizidae (sparrows)

5. Wood-Warblers Rearrange
It's difficult to give a decent overview of this reshuffling of Parulidae without images, so I recommend checking out the proposal on this one.  There's a lot to get used to here...

First of all, forget about the genera Parula, Dendroica, and Wilsonia.  They've all been moved into other genera!
1. Formerly of Parula, Crescent-chested and Flame-throated Warblers have been moved into Oreothlypis.  You remember Oreothlypis, all those warblers that used to be called Vermivora?  But what about the parulas, you ask?  Newly christened Setophaga (see below).
2. American Redstart is no longer lonely in its own genus (Setophaga).  It's been lumped with all the (formerly known as) Dendroica warblers, a move which makes sense.  But since Setophaga has priority, that's what they will all be called, including Northern and Tropical Parula, which are now included in this group.
3. The warblers formerly known as Wilsonia have been scattered around to new genera.  Hooded Warbler joins the party in Setophaga.  Wilson's and Canada Warblers, along with Red and Pink-headed Warblers (formerly of Ergaticus), have been merged with Red-faced Warbler and its genus, Cardellina.

Another big change is the near-extermination of Oporornis.  It turns out that Kentucky, Mourning, and MacGillivray's Warblers are more closely related to yellowthroats (genus Geothlypis).  Connecticut Warbler, that strange creature that walks rather than hops, stays cozy in Oporornis.

The tropical-minded will be interested in the splitting of the genus Basileuterus.  The majority of North American species were split off as Myiothlypis, although none of these occur in the ABA-area.  Rufous-capped and Golden-crowned Warblers remain Basileuterus, and Fan-tailed Warbler was merged into it as well.

How about an overview of North American Parulid genera!
- Several monotypic genera remain unchanged, including Black-and White, Prothonotary, and Swainson's Warblers and Ovenbird.
- Parkesia includes the two waterthrushes
- Vermivora includes Bachman's, Blue-winged and Golden-winged Warblers
- Oreothlypis includes all the former Vermivora, along with Crescent-chested and Flame-throated Warblers
- Geothlypis includes the yellowthroats along with Kentucky, Mourning and MacGillivray's Warblers
- Setophaga includes all former Dendroica, American Redstart, and Hooded Warbler
- Myiothlypis includes a bunch of the former Basileuterus
- Basileuterus, much reduced, now includes Fan-tailed Warbler
- Cardellina includes Red-faced, Red, Pink-headed, Wilson's, and Canada Warblers
- Myioborus remains unchanged.  Good ol' whitestarts.

Whew, that was exciting.  The biggest changes for me will be the name change for Common Gallinule and the warbler reshuffling.  I'll have to catch myself when I write "COMO" in my notes (COGA now) and when I start talking about Dendroica chip notes.

Folks may be interested in hearing about some proposals that didn't pass.  Some of these may well be valid changes that come up again after further research.
- Split Mountain Chickadee
- Split Yellow-rumped Warbler
- Change the names of Winter and Pacific Wrens to Western and Eastern Winter Wren
- Recognize Mexican Duck as a full species

Cardellina canadensis

1 comment:

  1. Great summary, = thank you for making busy birding life a bit more simple !
    Yellowbilled Tours Field Guide
    Rich Cimino
    Alameda County, California