L. David Mech is a wildlife research biologist with the U.S. Fish and Wildlife Service and a professor in the department of Fisheries and Wildlife at the University of Minnesota. He is the author of The Wolves of Isle Royale and The Wolf: The Ecology and Behavior of an Endangered Species (available from Minnesota). Mech's long experience as a radio-tracker dates back to the developmental work done at Minnesota in the early 1960s.