Over most of North America, cormorant ID used to be easy. True, there were multiple species on the Pacific Coast, a couple along the northern Atlantic Coast, and Neotropic Cormorants in part of coastal Texas and extreme southwestern Louisiana. But everywhere else, throughout the interior and the southeastern coast, it was safe to call any cormorant a Double-crested.
That’s no longer true. In recent decades the Neotropic Cormorant has greatly expanded its range. It nests commonly in the interior of Texas and Louisiana, as well as Arkansas, Oklahoma, New Mexico, and Arizona. It’s found regularly in California, Kansas, Mississippi, and Florida. Strays wander more widely every year, as far as New Jersey, Ontario, Minnesota, and Idaho. Apparently, Neotropic Cormorants could show up anywhere, and birders everywhere have reason to watch for them.