A major function of the American Birding Association Checklist Committee (ABA-CLC) is to vote on the addition of new species to the ABA Checklist. Other roles include reviewing and revising ABA Codes covering ease of observation in the ABA Area, as well as updating and maintaining the ABA Checklist regarding taxonomic sequence, standard English and scientific names, and four-letter alpha codes. The eight voting members of the ABA-CLC are Luke DeCicco (Kansas), Doug Gochfeld (New York), Melissa Hafting (British Columbia), Lauren Harter (Louisiana), Matt Heindel (Texas), Alvaro Jaramillo (Ontario), Mark Lockwood (Texas), and Marky Mutchler (Illinois). Peter Pyle (California) serves as the non-voting Secretary of the ABA-CLC. Each voting member votes to accept or not accept a species’ addition to the ABA Checklist based on evidence from one or more records in the ABA Area. An 8–0 or 7–1 tally is needed for acceptance to the Checklist following up to three rounds of voting.
Since the publication of our 35th annual report in Dec. 2024, the ABA-CLC has accepted five new species to the ABA Checklist:
European Herring Gull (Larus argentatus), by a vote of 7–1, based primarily on a well-documented adult in Newfoundland on 1 Jan. 2006, although other records could also have been considered by ABA-CLC members. There was general concern that separation among the European Herring Gull, the American Herring Gull (L. smithsonianus) and Vega Gull (L. vegae) is and will continue to be difficult given variation in each of these gulls in the multi-species complex in which they are members. The European Herring Gull has been assigned ABA Code 5 until its status can become more clearly resolved.
Eastern Cattle-Egret (Ardea coromanda), by a vote of 8–0, based primarily on a specimen taken on Agattu Island, Alaska, on 16 June 1988, but also on a bird photographed on Midway Atoll, Hawaiian Islands, in June–July 1997. As with the European Herring Gull, the Eastern Cattle-Egret is a recent split, prompting the ABA-CLC’s vote. The Eastern Cattle-Egret is assigned to ABA Code 5, reflecting the fact that there are fewer than five reports from the ABA Area.
Little White-Tern (Gygis microrhyncha), by a vote of 8–0, based on a specimen collected on Oahu, Hawaii, on 21 Apr. 1924. This is the only record of this species for the ABA Area, necessitating this vote. It is assigned ABA code 5. The ABA’s decision was based on analysis of a photograph of this specimen, below that of a Blue-billed White-Tern (L. candida). The Little White-Tern is another recent “split,” prompting the ABA-CLC’s action in the matter.
Hen Harrier (Circus cyaneus), by a vote of 8–0, based on a specimen of a partial wing found on Attu Island, Alaska, in early June 1999. It is assigned ABA Code 5, although there are additional records, which may result in reassignment to Code 4, pending validation of four or more of these records. Evaluation of Hen Harrier records has begun in earnest only relatively recently, on the heels of a 2016 split with the Northern Harrier (C. hudsonius), widespread in the ABA Area.
Oriental Honey-buzzard (Pernis ptilorhynchus), by a vote of 8–0, based on a record supported by multiple photographs from Shemya Island, Alaska, on 27 May 2024. It is assigned ABA Code 5.
The ABA-CLC voted on and did not accept six species involving five records, summarized below:
Pallid Swift (Apus pallidus), by a vote of 2–6, based on a record of a bird found on a street in Montreal, Québec, rehabilitated and released in June 2007. Photographs of this bird indicated this identification, but ABA-CLC members were not convinced that the Asian subspecies of the Common Swift (A. apus pekinensis) was ruled out.
Baillon’s Crake (Zapornia pusilla), by a vote of 0–8, based on a sight record from Attu Island, Alaska, on 20–21 Sept. 2000. Although the ABA-CLC does not have a policy regarding sight-only records, the ABA-CLC concluded there was not enough information to eliminate other Asian species of Crakes.
Eurasian Bittern (Botaurus stellaris), by a vote of 2–6, based on a record of a Botaurus bittern from Buldir Island, Alaska, on 13 and 25 June 2012. Photographs were suggestive of this species but most members concluded that the American Bittern (B. lentiginosus) was not fully eliminated.
Great White Pelican (Pelecanus onocrotalus), by votes of 5–3 and 3–5, based on an individual of this species seen sporadically and at various locations in Florida from Feb. 2016 to Jan. 2021. In the end, the ABA-CLC voted to not accept this as necessarily a natural vagrant, and this species remains on Provisional List B of the ABA Checklist for species of certain identification but questionable provenance recorded in the ABA Area.
Great Tit (Parus major) and Asian Tit (P. cinereus). The ABA-CLC voted on a sight record of a bird of genus Parus from Little Diomede Island, Alaska, on 2 Sept. 1988. ABA-CLC members indicated support for one of these two species, but it was not added to the ABA Checklist, by votes of 0–8 for Great Tit and 2–6 for Asian Tit, because it was difficult to determine which species was involved. As evident from these votes, ABA-CLC members thought Asian Tit was more fully supported by the description. Great Tit, Baillon’s Crake, and Eurasian Bittern were voted on because these records have been accepted as these species by eBird; note also that the Great Tit is on Provisional List A of the ABA Checklist (exotic species that may become established) due to breeding populations in Illinois and Wisconsin.
The ABA-CLC has two species currently under review, the Golden Pheasant (Chrysolophus pictus), based exotic populations on Maui, Hawaii, that were considered established by the Hawaii Bird Records Committee, and the Pearly-eyed Thrasher (Margarops fuscatus), based on a record from Key West, Florida, in Mar.–Apr. 2024 that has been accepted by the Florida Ornithological Society Records Committee. We are also aware of the potential addition of Military Macaw (Ara militaris) based on a recent record or records in Texas for which we await opinion from the Texas Bird Records Committee.
The ABA Checklist has also been updated according to taxonomic, naming, and linear sequence changes by the American Ornithological Society as reported in their 66th Supplement, published earlier this summer. These changes have resulted in the addition of two species due to splits. The Warbling Vireo (Vireo gilvus) was split into two species, the Eastern Warbling-Vireo (which retains the name V. gilvus) and the Western Warbling-Vireo (V. swainsoni). And the White Tern (Gygis alba) has been split into three species, two of which are considered to have been documented for the ABA Area: the Blue-billed White-Tern (G. candida) and the Little White-Tern (see above). These changes and the above additions bring the primary ABA Checklist to 1,158 species. Taxonomic revisions by the AOS have also resulted in 12 changes to standard English names and 11 changes to scientific names, and the re-arrangement in the linear sequences of species within and/or among the orders Columbiformes and Gruiformes, the families Laridae and Threskiornithidae, and the genus Accipiter.
More discussion regarding all of these decisions will be found in our 36th annual report, to be published in North American Birds in Dec. 2025.
Peter Pyle, Chair
ABA Checklist Committee
A major function of the American Birding Association Checklist Committee (ABA-CLC) is to vote on the addition of new species to the ABA Checklist. Other roles include reviewing and revising ABA Codes covering ease of observation in the ABA Area, as well as updating and maintaining the ABA Checklist regarding taxonomic sequence, standard English and scientific names, and four-letter alpha codes. The eight voting members of the ABA-CLC are Luke DeCicco (Kansas), Doug Gochfeld (New York), Melissa Hafting (British Columbia), Lauren Harter (Louisiana), Matt Heindel (Texas), Alvaro Jaramillo (Ontario), Mark Lockwood (Texas), and Marky Mutchler (Illinois). Peter Pyle (California) serves as the non-voting Secretary of the ABA-CLC. Each voting member votes to accept or not accept a species’ addition to the ABA Checklist based on evidence from one or more records in the ABA Area. An 8–0 or 7–1 tally is needed for acceptance to the Checklist following up to three rounds of voting.
Since the publication of our 35th annual report in Dec. 2024, the ABA-CLC has accepted five new species to the ABA Checklist:
European Herring Gull (Larus argentatus), by a vote of 7–1, based primarily on a well-documented adult in Newfoundland on 1 Jan. 2006, although other records could also have been considered by ABA-CLC members. There was general concern that separation among the European Herring Gull, the American Herring Gull (L. smithsonianus) and Vega Gull (L. vegae) is and will continue to be difficult given variation in each of these gulls in the multi-species complex in which they are members. The European Herring Gull has been assigned ABA Code 5 until its status can become more clearly resolved.
Eastern Cattle-Egret (Ardea coromanda), by a vote of 8–0, based primarily on a specimen taken on Agattu Island, Alaska, on 16 June 1988, but also on a bird photographed on Midway Atoll, Hawaiian Islands, in June–July 1997. As with the European Herring Gull, the Eastern Cattle-Egret is a recent split, prompting the ABA-CLC’s vote. The Eastern Cattle-Egret is assigned to ABA Code 5, reflecting the fact that there are fewer than five reports from the ABA Area.
Little White-Tern (Gygis microrhyncha), by a vote of 8–0, based on a specimen collected on Oahu, Hawaii, on 21 Apr. 1924. This is the only record of this species for the ABA Area, necessitating this vote. It is assigned ABA code 5. The ABA’s decision was based on analysis of a photograph of this specimen, below that of a Blue-billed White-Tern (L. candida). The Little White-Tern is another recent “split,” prompting the ABA-CLC’s action in the matter.
Hen Harrier (Circus cyaneus), by a vote of 8–0, based on a specimen of a partial wing found on Attu Island, Alaska, in early June 1999. It is assigned ABA Code 5, although there are additional records, which may result in reassignment to Code 4, pending validation of four or more of these records. Evaluation of Hen Harrier records has begun in earnest only relatively recently, on the heels of a 2016 split with the Northern Harrier (C. hudsonius), widespread in the ABA Area.
Oriental Honey-buzzard (Pernis ptilorhynchus), by a vote of 8–0, based on a record supported by multiple photographs from Shemya Island, Alaska, on 27 May 2024. It is assigned ABA Code 5.
The ABA-CLC voted on and did not accept six species involving five records, summarized below:
Pallid Swift (Apus pallidus), by a vote of 2–6, based on a record of a bird found on a street in Montreal, Québec, rehabilitated and released in June 2007. Photographs of this bird indicated this identification, but ABA-CLC members were not convinced that the Asian subspecies of the Common Swift (A. apus pekinensis) was ruled out.
Baillon’s Crake (Zapornia pusilla), by a vote of 0–8, based on a sight record from Attu Island, Alaska, on 20–21 Sept. 2000. Although the ABA-CLC does not have a policy regarding sight-only records, the ABA-CLC concluded there was not enough information to eliminate other Asian species of Crakes.
Eurasian Bittern (Botaurus stellaris), by a vote of 2–6, based on a record of a Botaurus bittern from Buldir Island, Alaska, on 13 and 25 June 2012. Photographs were suggestive of this species but most members concluded that the American Bittern (B. lentiginosus) was not fully eliminated.
Great White Pelican (Pelecanus onocrotalus), by votes of 5–3 and 3–5, based on an individual of this species seen sporadically and at various locations in Florida from Feb. 2016 to Jan. 2021. In the end, the ABA-CLC voted to not accept this as necessarily a natural vagrant, and this species remains on Provisional List B of the ABA Checklist for species of certain identification but questionable provenance recorded in the ABA Area.
Great Tit (Parus major) and Asian Tit (P. cinereus). The ABA-CLC voted on a sight record of a bird of genus Parus from Little Diomede Island, Alaska, on 2 Sept. 1988. ABA-CLC members indicated support for one of these two species, but it was not added to the ABA Checklist, by votes of 0–8 for Great Tit and 2–6 for Asian Tit, because it was difficult to determine which species was involved. As evident from these votes, ABA-CLC members thought Asian Tit was more fully supported by the description. Great Tit, Baillon’s Crake, and Eurasian Bittern were voted on because these records have been accepted as these species by eBird; note also that the Great Tit is on Provisional List A of the ABA Checklist (exotic species that may become established) due to a population Wisconsin.
The ABA-CLC has two species currently under review, the Golden Pheasant (Chrysolophus pictus), based exotic populations on Maui, Hawaii, that were considered established by the Hawaii Bird Records Committee, and the Pearly-eyed Thrasher (Margarops fuscatus), based on a record from Key West, Florida, in Mar.–Apr. 2024 that has been accepted by the Florida Ornithological Society Records Committee. We are also aware of the potential addition of Military Macaw (Ara militaris) based on a recent record or records in Texas for which we await opinion from the Texas Bird Records Committee.
The ABA Checklist has also been updated according to taxonomic, naming, and linear sequence changes by the American Ornithological Society as reported in their 66th Supplement, published earlier this summer. These changes have resulted in the addition of two species due to splits. The Warbling Vireo (Vireo gilvus) was split into two species, the Eastern Warbling-Vireo (which retains the name V. gilvus) and the Western Warbling-Vireo (V. swainsoni). And the White Tern (Gygis alba) has been split into three species, two of which are considered to have been documented for the ABA Area: the Blue-billed White-Tern (G. candida) and the Little White-Tern (see above). These changes and the above additions bring the primary ABA Checklist to 1,158 species. Taxonomic revisions by the AOS have also resulted in 12 changes to standard English names, and 11 changes to scientific names, and the re-arrangement in the linear sequences of species within and/or among the orders Columbiformes and Gruiformes, the families Laridae and Threskiornithidae, and the genus Accipiter.
More discussion regarding all of these decisions will be found in our 36th annual report, to be published in North American Birds in Dec. 2025.
Peter Pyle, Chair
ABA Checklist Committee
Peter Pyle, Staff Biologist with The Institute for Bird Populations, is an expert on molt and author of the two-volume Identification Guide to North American Birds. Also an expert on the birds of Hawaii, he puts his knowledge to use as Chair of the ABA Checklist Committee.
