This was a smaller bird, three-quarters the size of the Carolina parakeet. Rarities include sets of passenger pigeon, Carolina parakeet, and Bachman's warbler eggs. Two birds, the passenger pigeon and the Carolina parakeet, are entirely extinct. The Carolina parakeet had the northern-most range of any known parrot. The Carolina parakeet was a remarkably social bird, living in vast flocks. The extinct "Conuropsis carolinensis", or Carolina parakeet was an exception. Carolina parakeet, passenger pigeon, Labrador duck, great auk, pinnated grouse, and, possibly, the Eskimo curlew.