The primary role of the ABA Checklist Committee (ABA-CLC) is to vote on the addition of new species to the ABA Checklist. Secondary roles include reviewing and revising ABA Codes covering ease of observation in the ABA Area and updating and maintaining the ABA Checklist regarding taxonomic sequence, common and scientific names, and four-letter alpha codes. Currently, the eight voting members of the ABA-CLC are Luke DeCicco (Kansas), Doug Gochfeld (New York), Lauren Harter (Louisiana), Matt Heindel (Texas), Alvaro Jaramillo (California), Andy Kratter (Florida), Marky Mutchler (Illinois), and David Sibley (Massachusetts). Each member votes to accept or not accept a species’s 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 our update in July 2024, the CLC has accepted three species to the ABA Checklist:

Eurasian Sparrowhawk (Accipiter nisus), by a vote of 7–1, based on a record from Adak Island, Alaska, on 21 September 2016. This record was re-reviewed by the CLC after being accepted as countable on eBird-generated lists for the ABA Area. The CLC had not accepted this species by a vote of 6-2 in 2018.

Blue Rock-Thrush (Monticola solitarius), by a vote of 8-0, based on records of one or two birds from Hug Point south of Canon Beach, Oregon, on 21 April 2024 and Southeast Farallon Island off San Francisco, California, 25-28 April 2024, following unanimous support from both local bird records committees. The CLC also indicated support for a record from Goldpan Provincial Park near Spences Bridge, British Columbia, on 6 June 1997.

Lavender Waxbill (Glaucestrilda caerulescens), by a vote of 7–1 on the first round, as an established exotic. Populations on Hawai’i Island were deemed established after the submission of more data since the CLC did not accepted the species in 2017. The populations is also accepted as established by eBird, the AOS, and the Hawaii Bird Records Committee.

The CLC voted on and did not accept two species:

House Crow (Corvus splendens), 3–5, based on records from Florida in 2002-2018. Birds arriving to the ABA Area were known to ride ships without being constrained. Based on differing philosophies on the provenance of known, ship-assisted vagrants, the CLC is not ready to accept such records, although they may consider doing so in the future. Following eBird, this species will be placed on the ABA Provisional List as a ship-assisted species.

Cattle Tyrant (Machetornis rixosa), 2-6, based on a record from Corpus Christi, Texas, in September 2023 to May 2024. CLC members who voted for this record agreed that ship-assisted vagrants to the ABA Area are acceptable, while those that voted against the record are not yet ready to accept such records. There was also opinion that acceptable ship-assisted vagrants should be known to have arrived unrestrained on a ship, which was not the case with this record. Following eBird, this species will be placed on the ABA Provisional List as a species of unknown provenance.

The CLC has three species currently under review: Great White Pelican (based on a long-recorded bird in Florida), Hen Harrier (based on a specimen record from Alaska), and Eastern Cattle-Egret (based on records from Alaska and Midway Atoll in the Hawaiian Islands). Review of the cattle-egret follows its split from Western Cattle-Egret by Clements/eBird and the fact that it would be a Code 5 species (< 5 records) in the ABA Area. In the coming months we will review records of Baillon’s Crake, Great Bittern, and Eurasian Tit, due to their counting on eBird-generated lists for the ABA Area.

The ABA Checklist has also been updated according to taxonomic, naming, and sequence changes by the American Ornithologists’ Society as reported in the 65th Supplement to their Check-list of North American Birds (link). These changes have resulted in the addition of three species due to splits (Scopoli’s Shearwater, Cocos Booby, and Siberian Pipit) and the deletion of one species due to lumps (Hoary Redpoll). These changes, the above additions, and additions of extirpated exotic species bring the ABA Checklist to 1,152 species on its primary list.

Changes by the AOS have also resulted in 10 changes to English names, 14 changes to scientific names, and the re-arrangement of 31 species. Changes in naming have also affected the number of species with discrepancies between Clements/eBird and AOS names, with 16 species being removed, (6 by alignment of English and 10 by alignment of scientific names), and six being added (five in English and one in Scientific names). The list of discrepancies now totals 23, 16 in English names and 7 in scientific names.

Changes to the ABA Provisional Lists of exotic species (with increasing populations) include the removal of Lavender Waxbill, due to its addition to the primary list, and the addition of Great Tit (due to a previous omission). No changes occur to the Provisional List of ship-assisted species or species of unknown provenance. The CLC is currently in discussion with the eBird regarding further updates to these Provisional lists.

More discussion regarding all of these updates can be found in an article in the July 2024 issue North American Birds (link).

The updated ABA Checklist can be found here >>

Peter Pyle is an expert on molt, especially as it pertains to aging birds. He is the author of the two-volume Identification Guide to North American Birds, which is widely admired by banders and serious birders. Peter serves as an Editorial Consultant at Birding, a prolific contributor to ornithological literature, and current Chair of the ABA Checklist Committee.