There seems to be just one flaw in this scheme: an ordinary black bear is only about half as large as a grizzly, yet a black bear cub when born is much larger than a grizzly cub.

Now why the devil that should be--" Bruce interrupted his friend with a good-natured laugh.
"That's easy--easy, Jimmy!" he exclaimed.

"Do you remember last year when we picked strawberries in the valley an' threw snowballs two hours later up on the mountain?
Higher you climb the colder it gets, don't it?
Right now--first day of July--you'd half freeze up on some of those peaks! A grizzly dens high, Jimmy, and a black bear dens low.

When the snow is four feet deep up where the grizzly dens, the black bear can still feed in the deep valleys an' thick timber.

He goes to bed mebby a week or two weeks later than the grizzly, an' he gets up in the spring a week or two weeks earlier; he's fatter when he dens up an' he ain't so poor when he comes out--an' so the mother's got more strength to give to her cubs.