The Committee on Classification and Nomenclature of the American Ornithologists' Union has just published the 49th Supplement to the AOU "Check-List of North American Birds". As usual, there are some changes that affect Wisconsin's list. I'll get to that in a minute.
I'm re-working the Annotated Checklist for Wisconsin right now, and expect it to be published on the WSO website in about a month. The total number of valid species on the list is 429. Changes include the acceptance of the Hooded Oriole to the WI list, and the addition of Virginia Warbler to the hypothetical list.
Changes include a reworking of gulls. You'll see some new names for certain genera; including several species that were formerly placed in the genus Larus. Here is a section from the new N. American list:
(These are in the sufamily Larinae):
Rissa tridactyla Black-legged Kittiwake.
Pagophila eburnea Ivory Gull.
Xema sabini Sabine’s Gull.
Chroicocephalus philadelphia Bonaparte’s Gull.
Chroicocephalus ridibundus Black-headed Gull.
Hydrocoloeus minutus Little Gull.
Rhodostethia rosea Ross’s Gull.
Leucophaeus atricilla Laughing Gull.
Leucophaeus pipixcan Franklin’s Gull.
Larus crassirostris Black-tailed Gull.
Larus heermanni Heermann’s Gull.
Larus canus Mew Gull.
Larus delawarensis Ring-billed Gull.
Larus occidentalis Western Gull.
Larus californicus California Gull.
Larus argentatus Herring Gull.
Larus thayeri Thayer’s Gull.
Larus glaucoides Iceland Gull.
Larus fuscus Lesser Black-backed Gull.
Larus schistisagus Slaty-backed Gull.
Larus glaucescens Glaucous-winged Gull.
Larus hyperboreus Glaucous Gull.
Larus marinus Great Black-backed Gull
More notes to come.