The British Ornithological Union (BOU) Records Committee has just released the seventh report of the Taxonomic Sub-committee. There are several changes suggested that are of interest to North American birders as sometimes these changes made by the BOU end up influencing similar committees in the American Ornithological Union (AOU).
The first change is the split of the Whimbrel into the Hudsonian Whimbrel Numenius hudsonicus and the Eurasian Whimbrel N. phaeopus. This split was based on differences in plumage as well as morphological differences. Below are range maps showing locations where people recorded these two new split species of Whimbrel.
The BOU report also split the Sandwich Tern, elevating the New World subspecies to full species status and renaming it to Cabot’s Tern Sterna acuflavida while the Old World species remains Sandwich Tern S. sandvicensis. It will be interesting to see if the AOU makes a name change for the Sandwich Tern as well, or if we will simply refer to it as American Sandwich Tern. Below are range maps from eBird showing the distribution of all species formerly called Sandwich Tern (left) and where people have reported Cabot’s Tern (right). If this split becomes oficial in North America as well, expect the distribution of Cabot’s Tern to look more complete when eBird converts New World records to Cabot’s.
This report also mentioned several splits that the AOU has already recommended or discussed including the Old World/New World split of Snowy Plovers into Kentish Charadrius alexandrinus and Snowy Plover Charadrius nivosus. They also realigned the New World warblers to match the changes that were recently adopted by the AOU.