The 2017 American Ornithological Society Check-list Supplement was notable for the taxonomic decisions that were not made as much as those that were. Yellow-rumped Warbler and Willet were not split, but Cassia Crossbill was. We also saw the unprecedented lump of Thayer's Gull into the holarctic Iceland Gull. Biologist Nick Block returns along with Birder's Guide editor Michael Retter to discuss the changes made and the AOS's process. Also, we hear from Laura Erickson, author of the new ABA Field Guide to Birds of Minnesota, about writing the book and some of her favorite experiences birding in that part of the world. And Nate has a little something to say about the rise of millennial birders via this Maclean's article.  Subscribe to the podcast at Apple Podcasts, Stitcher, and Google Play, and please leave a rating or a review if you are so inclined! We appreciate it!