Meet the newest species of bird in North America: A Gunnison Sage-Grouse specimen arrives in Chicago

The last new species of bird to be described in the United States--in fact the first since the 19th century--was Gunnison Sage-Grouse (Centrocercus minimus), described to science in 2000 on the basis of behavioral, vocal, and morphological (size and plumage) differences from its larger, more widespread cousin, the Greater Sage-Grouse (Centrocercus urophasianus). When the paper describing the new species came out, The Field Museum already held several specimens in its collection, but like all specimens of Gunnison Sage-Grouse they had been assumed to be Greater Sage-Grouse (pictured above).

The most recent specimen of either sage-grouse in the museum's collection is from all the way back in 1933, so when we were contacted by a colleague at Colorado Parks and Wildlife who had found a road-kill Gunnison Sage-Grouse, we enthusiastically accepted the donation. The colleague, Nathan Seward, had fond memories of his time spent at The Field Museum as a child,  so when found he found an unhatched and abandoned Gunnison Sage-Grouse egg two years ago he contacted us about donating it. That egg is now part of the museum's egg collection, and now we have a study skin (and our first tissue sample, which can be used in genetic studies) from the same population.

Read all about Gunnison Sage-Grouse. The species is being considered for listing under the federal Endangered Species Act (ESA)--it is already listed as Endangered by Birdlife International--but listing under the ESA is politically fraught, as shown in various cases across the country. Regardless, it's a beautiful and charismatic bird and a valuable addition to The Field Museum's research collection.