American Birding Podcast



2019 AOS Supplement is Out!

Every summer, birders anxiously await publication of the “Check-list Supplement” by the American Ornithological Society’s Committee on Classification and Nomenclature of North and Middle American Birds (a.k.a. the NACC). The supplement, available here, details revisions to the NACC’s Check-list. Below is a brief rundown of those changes.You can read all the proposals on which the NACC voted this year at Later in the year, be sure to check out ABA’s annual “Check-list Redux” in Birding magazine. There, you’ll find photos, maps, and more detailed analysis of these changes.

Species marked with asterisks (*) below are those which do not appear on the ABA Checklist. Nowadays, it can be assumed that any change in taxonomy is due (at least partly) to analysis of new genetic data, so that is not always mentioned below. As a general policy, the NACC accepts as additions to its North American Check-list any species the ABA’s Checklist Committee adds to its list. Those changes are not listed here.

This year, the topics most likely to generate discussion are splits of White-winged Scoter and an English name change for Blue-throated Hummingbird. There were also genus-level changes affecting some familiar warblers and storm-petrels.



Three-way split of White-winged Scoter


Velvet Scoter* (Melanitta fusca)

White-winged Scoter (Melanitta deglandi)

Stejneger’s Scoter (Melanitta stejnegeri)


White-winged Scoter by Peter Pearsall/U.S. Fish and Wildlife Service

White-winged Scoter (Melanitta fusca, sensu lato) has been split into three species: Velvet Scoter (Melanitta fusca, sensu stricto), White-winged Scoter (Melanitta deglandi), and Stejneger’s Scoter (Melanitta stejnegeri). For most of us in North America, the effect is a change in scientific name of White-winged Scoter. Velvet and Stejneger’s scoters are Old World birds.

Velvet Scoter by Niklas Andersson

Velvet Scoter is found in western and central Eurasia; it is casual in Greenland, but no accepted records exist for the ABA Area. The adult male’s body is completely jet black, and the lack of red and near-lack of a black bump on the adult male’s bill is unique among the three species. The adult male also has a shorter white mark under the eye with less “swish” (upward curvature) at the rear. Female and immature Velvet scoters also show less of a bump on the bill than those of the other two species and differ in subtleties of head shape, but their identification is very difficult even with an excellent view.

Stejneger’s Scoter by Niklas Andersson

Stejneger’s Scoter is found in northeast Eurasia. It occurs casually in Alaska, specifically in the Bering Sea. The species has been recorded in northern Europe, so birders along the east coast of North America (such as in Newfoundland & Labrador) should be on the lookout. Adult male Stejneger’s differ from White-winged in having a flatter forehead, more pronounced bill bump, and a different pattern of red, yellow, and orange on the bill. Both Velvet and Stejneger’s differ from White-winged Scoter in having black flanks as adult males; the flanks are brown in White-winged. Female and immature Stejneger’s Scoters also have the flatter forehead, but as with Velvet Scoter, their identification is very difficult.


Say hello to the mountain-gems!

Blue-throated Hummingbird Blue-throated Mountain-gem

Amethyst-throated Hummingbird Amethyst-throated Mountain-gem

Blue-throated Mountain-gem by Bettina Arrigoni

The English name of Lampornis clemenciae has changed from Blue-throated Hummingbird to Blue-throated Mountain-gem. The same goes for Lampornis amethystinus, which is now Amethyst-throated Mountain-gem. Why? There are at least five (depending on whom you ask) other species of Lampornis in Middle America, and they are all called “Somethingorother Mountain-gem”. This wise move standardizes the English names of all the species in the genus. I hope the committee follows this promising trend and gives us Lucifer Sheartail and Bahama Sheartail next!


Great-winged Petrel split

Great-winged Petrel* (Pterodroma macroptera)

Gray-faced Petrel (Pterodroma gouldi)

All accepted “Great-winged Petrel” records in the ABA Area are thought to pertain to Gray-faced Petrel.


Ground-Doves lose their hyphens

Common Ground-Dove ➛ Common Ground Dove

Plain-breasted Ground-Dove* ➛ Plain-breasted Ground Dove

Ruddy Ground-Dove ➛ Ruddy Ground Dove

Blue Ground-Dove* ➛ Blue Ground Dove

Maroon-chested Ground-Dove* ➛ Maroon-chested Ground Dove

The NACC uses hyphens in “last names” to show that all the birds in a group are each other’s closest relatives (such as in the scrub-jays). These doves are not, however, so the hyphen goes.


Most of the the other changes which affect the ABA Area are changes to scientific names and the sequence of species on the checklist.


Split of Oreothypis

The warbler genus Oreothlypis has been split. As a result, only two species (one with records in the ABA Area) remain within it. All other species have been moved to Leiothlypis.

Crescent-chested Warbler (Oreothlypis superciliosa)

Flame-throated Warbler* (Oreothlypis gutturalis)

Tennessee Warbler (Oreothlypis peregrina Leiothlypis peregrina)

Orange-crowned Warbler (Oreothlypis celata Leiothlypis celata)

Colima Warbler (Oreothlypis crissalis Leiothlypis crissalis)

Lucy’s Warbler (Oreothlypis luciae Leiothlypis luciae)

Nashville Warbler (Oreothlypis ruficapilla Leiothlypis ruficapilla)

Virginia’s Warbler (Oreothlypis Virginia Leiothlypis virginiae)


Genus-level storm-petrel lump

All the members of Oceanodroma have been transferred to Hydrobates; formerly, the only Hydrobates found in the ABA Area was European Storm-Petrel. The North American species of Hydrobates are now as follows, in the following sequence.

European Storm-Petrel (Hydrobates pelagicus)

Fork-tailed Storm-Petrel (Oceanodroma furcata Hydrobates furcatus)

Ringed Storm-Petrel (Oceanodroma hornbyi Hydrobates hornbyi)

Swinhoe’s Storm-Petrel (Oceanodroma monorhis Hydrobates monorhis)

Leach’s Storm-Petrel (Oceanodroma leucorhoa Hydrobates leucorhous)

Townsend’s Storm-Petrel (Oceanodroma socorroensis Hydrobates socorroensis)

Ainley’s Storm-Petrel (Oceanodroma cheimomnestes Hydrobates cheimomnestes)

Ashy Storm-Petrel (Oceanodroma homochroa Hydrobates homochroa)

Band-rumped Storm-Petrel (Oceanodroma castro Hydrobates castro)

Wedge-rumped Storm-Petrel (Oceanodroma tethys Hydrobates tethys)

Black Storm-Petrel (Oceanodroma melania Hydrobates melania)

Guadalupe Storm-Petrel* (Oceanodroma macrodactyla Hydrobates macrodactylus)

Markham’s Storm-Petrel (Oceanodroma markhami Hydrobates markhami)

Tristam’s Storm-Petrel (Oceanodroma tristamiHydrobates tristami)

Least Storm-Petrel (Oceanodroma microsomaHydrobates microsoma)


New genus for Erckel’s Francolin

Erckel’s Francolin (Francolinus erckelii  Pternistis erckelii)

Francolinus, a genus of Old World “chickens” was split. Gray and Black francolins remain in the genus, but Erckel’s has a new home. It still occurs immediately after Black Francolin in the checklist sequence.

Split of Calliphlox

While Magenta-throated and Purple-throated woodstars remain in the genus, Bahama and Inagua woodstars are moved to a new genus, Nesophlox. They occur in the sequence below and immediately after Bee Hummingbird in the checklist sequence,

Bahama Woodstar (Calliphlox evelynae  Nesophlox evelynae)

Inagua Woodstar* (Calliphlox lyura  Nesophlox lyura)

Recent genetic data show that these two species fall into the sheartail clade, so it’s puzzling to me why this opportunity wasn’t taken to change the common names to Bahama Sheartail and Inagua Sheartail.


New sequence for frigatebirds

Lesser Frigatebird

Magnificent Frigatebird

Great Frigatebird


New sequence for cuckoos

Crotophaga (anis)
Tapera* (Striped Cuckoo)
Dromococcyx* (Pheasant Cuckoo)
Morococcyx* (Lesser Ground-Cuckoo)
Geococcyx (roadrunners)
Neomorphus* (Rufous-vented Ground-Cuckoo)
Cuculus (Common and Oriental cuckoos)
Coccycua* (Little Cuckoo)
Piaya* (Squirrel Cuckoo)
Coccyzus (Yellow-billed Cuckoo, etc.)


New sequence for Charadrius plovers


Eurasian Dotterel


Common Ringed Plover

Semipalmated Plover

Piping Plover

Little Ringed Plover

Lesser Sand-Plover

Greater Sand-Plover

Oriental Plover*

Wilson’s Plover

Collared Plover

Mountain Plover

Snowy Plover


New swallow sequence

Bank Swallow

Tree Swallow

Bahama Swallow

Violet-green Swallow

Golden Swallow*

Mangrove Swallow

Black-capped Swallow*

White-thighed Swallow*

Blue-and-white Swallow*

Northern Rough-winged Swallow

Southern Rough-winged Swallow*

Sinaloa Martin*

Brown-chested Martin

Caribbean Martin*

Purple Martin

Cuban Martin

Gray-breasted Martin

Southern Martin

Barn Swallow

Common House-Martin

Cliff Swallow

Cave Swallow


New sequence for New World sparrows (Passerellidae)

Yellow-throated Chlorospingus*

Ashy-throated Chlorospingus*

Sooty-capped Chlorospingus*

Common Chlorospingus*

Tacarcuna Chlorospingus*

Pirre Chlorospingus*

Rufous-winged Sparrow

Cinnamon-tailed Sparrow

Stripe-headed Sparrow*

Black-chested Sparrow*

Bridled Sparrow*

Botteri’s Sparrow

Cassin’s Sparrow

Bachman’s Sparrow

Grasshopper Sparrow

Olive Sparrow

Green-backed Sparrow*

Black-striped Sparrow*

Five-striped Sparrow

Black-throated Sparrow

Lark Sparrow

Lark Bunting

Chipping Sparrow

Clay-colored Sparrow

Black-chinned Sparrow

Field Sparrow

Brewer’s Sparrow

Worthen’s Sparrow

Costa Rican Brushfinch*

Black-headed Brushfinch*

Orange-billed Sparrow*

Green-striped Brushfinch*

Chestnut-capped Brushfinch*

Sooty-faced Finch*

Fox Sparrow

American Tree Sparrow

Volcano Junco*

Guadalupe Junco*

Dark-eyed Junco

Yellow-eyed Junco

Baird’s Junco*

Rufous-collared Sparrow*

White-crowned Sparrow

Golden-crowned Sparrow

Harris’s Sparrow

White-throated Sparrow

Sagebrush Sparrow

Bell’s Sparrow

Striped Sparrow*

Vesper Sparrow

LeConte’s Sparrow

Seaside Sparrow

Nelson’s Sparrow

Saltmarsh Sparrow

Baird’s Sparrow

Henslow’s Sparrow

Savannah Sparrow

Sierra Madre Sparrow*

Song Sparrow

Lincoln’s Sparrow

Swamp Sparrow

Large-footed Finch*

Zapata Sparrow*

Rusty-crowned Ground-Sparrow*

Canyon Towhee

White-throated Towhee*

Abert’s Towhee

California Towhee

White-eared Ground-Sparrow*

White-faced Ground-Sparrow*

Cabanis’s Ground-Sparrow*

Rusty Sparrow*

Rufous-crowned Sparrow

Oaxaca Sparrow*

Green-tailed Towhee

Spotted Towhee

Eastern Towhee

Collared Towhee*

Rufous-capped Brushfinch*

White-naped Brushfinch*

Yellow-thighed Brushfinch*

Yellow-green Brushfinch*


New family for laughingthrushes and leiothrix

Greater Necklaced Laughingthrush, Hwamei, and Red-billed Leiothrix (all Asian species established in Hawaii) are moved out of the family Timalliidae and into the “new” family, Leiothrichidae.



=== Further changes affecting only Middle America ===


Split of Vermiculated Screech-Owl

Middle American Screech-Owl (Megascops guatemalae)

Chocó Screech-Owl (Megascops centralis)

Vermiculated Screech-Owl (Megascops guatemalae, sensu lato) has been split into two species.


Goodbye, Orange-bellied Trogon!

Orange-bellied Trogon (Trogon aurantiiventris) has been lumped into Collared Trogon (T. collaris), which it resembles in every way except belly color.


Split of Green Parakeet


Green Parakeet (Psittacara holochlorus)

Socorro Parakeet (Psittacara brevipes)

Socorro Parakeet, endemic to Isla Socorro far off the western coast of Mexico, is now treated as a species distinct from Green Parakeet. The former differs from the latter in having a stouter bill, darker eyering, and very different voice. Here’s hoping the morphologically, ecologically, and vocally distinct Red-throated Parakeet gets the same treatment soon!


Split of Steely-vented Hummingbird

Blue-vented Hummingbird (Amazilia hoffmanni)

Steely-vented Hummingbird (Amazilia saucerottei)
Vocalizations, behavior, plumage, and genetics all point to the North American Blue-vented Hummingbird being treated a separate species form the South American Steely-vented Hummingbird. With this split, the latter is no longer considered to occur in North America.

The image at right shows a Blue-vented Hummingbird.
Split of White-lored Gnatcatcher

White-lored Gnatcatcher (Plioptila albiloris)

Yucatán Gnatcatcher (Polioptila albiventris)

Yucatán Gnatcatcher by René Valdés

Yucatán Gnatcatcher by René Valdés

Formerly considered a disjunct population of White-lored Gnatcatcher inhabiting the dry coastal desert strip along the N edge of the peninsula, Yucatán Gnatcatcher is now considered a distinct species. While they appear nearly identical, the two differ in voice and genetics. Yucatán Gnatcatcher’s closet relative instead seems to be the nearby North American population of Tropical Gnatcatcher.


English name and genus changes for Yellow-thighed and Yellow-green finches

Yellow-thighed Finch (Pselliophorus tibialis) Yellow-thighed Brushfinch (Atlapetes tibialis)

Yellow-green Finch (Pselliophorus luteoviridis) Yellow-green Brushfinch (Atlapetes luteoviridis)


Split of Claravis

Blue Ground Dove (Claravis pretiosa)

Maroon-chested Ground Dove (Claravis mondetoura Paraclaravis mondetoura), still occurring in this sequence.


Transfer of “Providencia Vireo”

Though considered by some a distinct species, “Providencia Vireo”, endemic to Colombia’s Isla de Providencia, has been considered by NACC a subspecies of Thick-billed Vireo (Vireo crassirostris). It is now considered a subspecies of Mangrove Vireo (Vireo pallens approximans). Note that while Isla de Providencia is owned by Colombia, it is east of Nicaragua and thus well within the NACC Area.


Split of Cyanocompsa

Blue-black Grosbeak (Cyanocompsa cyanoides Cyanoloxia cyanoides)

Blue Bunting (Cyanocompsa parellina)



Split of Tangara

Speckled Tanager (Tangara guttata  Ixothraupis guttata), now occurring immediately after Yellow-billed Cardinal in the sequence.

Azure-rumped Tanager (Tangara cabanisi Poecilostrepus cabanisi)

Gray-and-gold Tanager (Tangara palmeri ➛ Poecilostrepus palmeri), both now occurring in this sequence and immediately after Speckled Tanager.

Golden-hooded Tanager (Tangara larvataStilpnia larvata)

Lesser Antillean Tanager (Tangara cucullata ➛ Stilpnia cucullata), both now occurring in this sequence immediately following Palm Tanager.


Split of Tiaris

Cuban Grassquit (Tiaris canorusPonipara conora), after Yellow-shouldered Grassquit

Black-faced Grassquit (Tiaris bicolor ➛ Melanospiza bicolor), joining the genus of St. Lucia Black Finch and occurring immediately before it in the sequence.

Yellow-faced Grassquit remains in Tiaris and occurs immediately following Bananaquit in the sequence.


New species added because of records in Panama

Dwarf Cuckoo
(Coccycua pumilis), placed immediately after Little Cuckoo in the sequence.

Gray-capped Cuckoo (Coccyzus lansbergi), placed immediately after Black-billed Cuckoo in the sequence.



Splits involving extralimital species that result in no name change for North America:


Split of Band-rumped Storm-Petrel

Monteiro’s Storm-Petrel (Hydrobates monteiroi), formerly considered a subspecies of Band-rumped Storm-Petrel (H. castro), has been elevated the species status.


Split of Blue-black Grosbeak

Amazonian Grosbeak (Cyanoloxia rothschildii), formerly considered a subspecies of Blue-black Grosbeak (C. cyanoides), has been elevated to species status.




Proposals not accepted include

Split of Northern Fulmar (into Atlantic and Pacific)

Split of Middle American Screech-Owl (into Vermiculated and Guatemalan)

Split of Resplendent Quetzal (northern and southern populations)

Split of Hwamei (mainland and Taiwan)

Split of Harlan’s Hawk from Red-tailed Hawk

Change in scientific name of “Red-shafted Flicker”

Change in English name of McCown’s Longspur

Change in English name of Saltmarsh Sparrow

Transfer of the Costa Rican/Panamanian population of Lesser Violetear to Mexican Violetear

Transfer of Orinoco Goose from Neochen to Oressochen

Remving the hyphen from “mountain-gem”

Merging Melozone into Aimophila

Transfer of Blue Bunting into Passerina

Dropping the ‘s in birds named after people (e.g., Cooper Hawk, Wilson Warbler)