docdb,
There is a flim available called "Take a closer Look" that is helpful with judging bears, sexing, size and age to some extent. I was available several years back from the Yukon Fish & Game dept. . I learned of it from Phil Shoemaker, and he wrote of it in the APHA mag. I dont have my copy any longer my guide has it and uses it for his hunters, but maybe you can find one. It was time well spent. The tape mostly deals with coastal bears, but I think it would still be a help. The ears issue mentioned prior is good advise from what I have seen of live bears.
HBH