By the way, the wolves in Mr. Whetten’s photos on this page are gray wolves (Canis lupus), but they are most assuredly not Mexican gray wolves (the subspecies Canis lupus baileyi). There are no Mexican gray wolves in Yellowstone. They are present in the wild only in Arizona and New Mexico, mostly inside the Blue Range Wolf Recovery Area—with a handful of occasional dispersers outside the boundaries of the Apache and Gila National forests and the Fort Apache Indian Reservation. Also, there are no all-black Mexican gray wolves. They are all “multicolored,” similar to the wolf in the top photo.

For good comparison photos and info on distinguishing Mexican gray wolves and coyotes, check this page on the website of the Arizona Game and Fish Department.

http://www.azgfd.gov/w_c/es/wolf_difference.shtml