It was about one year ago when the American Ornithologists' Union published their last supplement to the Check-List of North American Birds. If you need a refresher, you can read about that supplement here.
The AOU has just released this year's supplement. Here, I will summarize those changes most relevant to ABA-area birders. If you want to read the full supplement, download the PDF here or read the proposals in their entirety here.
Two of these changes stand out, at least to me. First is the split of Xantus's Murrelet, giving us Scripps's and Guadalupe Murrelets. More fascinating to me is the taxonomic reshuffling of Falcons, Parrots, and Passerines with the findings that the three orders are relatively closely related!
More on these and other important changes:
1. Species Added
Bryan's Shearwater has been added to the AOU list as this species has been newly described from an old specimen (other specimens have since been identified as this species). It is considered accidental in Hawaii and not recorded from the ABA area, but this one is too interesting to leave out.
2. Splits and Lumps
- Galapagos Shearwater has been split from Audubon's Shearwater (but has never been recorded in the ABA area).
- Gray Hawk has been split, but the break between Gray and Gray-lined
Hawks is in Costa Rica, so the change doesn't affect the status of the
birds in the U.S.
- Xantus's Murrelet has been split into Scripps's Murrelet and
Guadalupe Murrelet. Scripps's is the more northerly-breeding and
generally the more commonly seen off the U.S. Pacific states. Guadalupe
is the more southerly-breeding, and though it does wander as far north as Washington (casually), it is found well offshore after breeding.
- Calliope Hummingbird is no longer in the monotypic genus Stellula, but is now included in Selasphorus. This is an obvious relationship and a welcome change!
- Sage Sparrow is no longer in the genus Amphispiza with Five-striped and Black-throated Sparrows, but in its own genus, Artemisospiza.
3. Name Changes
- The genus Caprimulgus has been split so that ABA-area nightjars are now in the genus Antrostomus
- House, Cassin's, and Purple Finches have been moved out of the Old World genus Carpodacus and into their very own Haemorhous. More fun to spell, not so fun to pronounce?
4. Taxonomic Reshuffling
- The linear sequence of hummingbirds and wrens are changed
- Research has shown that Falcons, Parrots and Passerines are sister groups, so the three orders (Falconiformes, Psittaciformes, and Passeriformes) are now grouped together in linear sequence.