New AOU Checklist for North America

The American Ornithologists' Union has released the 47th Supplement to their Checklist of North American Birds, the 6th supplement they have released since the publication of the Checklist's 7th edition. The supplement makes the following changes to the list:

Changes in this Supplement fall into the following categories: (1) three species are added because of splits from species already on the list (Calonectris edwardsii, Dendragapus fuliginosus, Loxigilla barbadensis); (2) one species is added because of new distributional information (Fregetta tropica); (3) two species replace others presently on the list because of splitting of extralimital forms (Cuculus optatus, Ficedula albicilla); (4) one species name (Streptopelia risoria) is changed because of recognition of its status as a feral form of S. roseogrisea; (5) one family is merged into another (Dendrocolaptidae into Furnariidae), with no resultant nomenclatural changes; (6) one subfamily is elevated to status of family (Stercorariidae), with no resultant nomenclatural changes; (7) one genus (Asturina) is merged with another (Buteo), resulting in a new name combination (B. nitidus); (8) one species (sissonii) is transferred from one genus (Thryomanes) to another (Troglodytes); and (9) two species (Myiozetetes similis, Catharus mexicanus), in addition to three of the four added to the entire list [see (1) and (2) above], are added to the list of species known to occur in the United States.

Of these, the one likely to affect the most North American birders is the first. Blue Grouse (Dendrapagus obscurus) has been split into two species, Dusky Grouse (D. obscurus) and Sooty Grouse (D. fuliginosus). The two species were split based on mitochodrial DNA and behavioral evidence. Sooty Grouse inhabits the Pacific coast, while Dusky Grouse claims the interior mountain west. There is an intergrade zone in Washington state. The paper that led to the split is here.

In addition to the changes listed in the first blockquote, the AOU has rearranged species into new genera within the sandpiper and tern families. In the case of sandpipers, species in the
Heteroscelus and Catoptrophorus genera have been moved to the genus Tringa, so that the list is now as follows:

Xenus cinereus Terek Sandpiper
Actitis hypoleucos Common Sandpiper
Actitis macularius Spotted Sandpiper
Tringa ochropus Green Sandpiper
Tringa solitaria Solitary Sandpiper
Tringa brevipes Gray-tailed Tattler
Tringa incana Wandering Tattler
Tringa erythropus Spotted Redshank
Tringa melanoleuca Greater Yellowlegs
Tringa nebularia Common Greenshank
Tringa semipalmata Willet
Tringa flavipes Lesser Yellowlegs
Tringa stagnatilis Marsh Sandpiper
Tringa glareola Wood Sandpiper
Tringa totanus Common Redshank

Five genera have been split from the Sterna genus in the tern family: Onychoprion, Sternula, Gelochelidon, Hydroprogne, and Thalasseus. The new order is as follows:

Anous stolidus Brown Noddy
Anous minutus Black Noddy
Procelsterna cerulea Blue-gray Noddy
Gygis alba White Tern
Onychoprion fuscatus Sooty Tern
Onychoprion lunatus Gray-backed Tern
Onychoprion anaethetus Bridled Tern
Onychoprion aleuticus Aleutian Tern
Sternula albifrons Little Tern
Sternula antillarum Least Tern
Sternula superciliaris Yellow-billed Tern
Phaetusa simplex Large-billed Tern
Gelochelidon nilotica Gull-billed Tern
Hydroprogne caspia Caspian Tern
Larosterna inca Inca Tern
Chlidonias niger Black Tern
Chlidonias leucopterus White-winged Tern
Chlidonias hybrida Whiskered Tern
Sterna dougallii Roseate Tern
Sterna hirundo Common Tern
Sterna paradisaea Arctic Tern
Sterna forsteri Forster’s Tern
Thalasseus maximus Royal Tern
Thalasseus bergii Great Crested Tern
Thalasseus sandvicensis Sandwich Tern
Thalasseus elegans Elegant Tern