He knew well that a full-grown cow moose was an awkward antagonist to tackle when she was in earnest.
This one seemed to him to be very much in earnest.

He hesitated and stopped his rush when about halfway down the bank.

Caution began to cool his vengeful humor.

After all, it seemed there was really no luck for him in a fawn-colored calf.

He'd try a red one or a black-and-white one next time.