Later in that book he writes about dispatching a favorite aging horse "Old Kite" in the American West, then leaving the carcass to bait eagles- and later dispatching a Bald Eagle (very protected species by the way) with a .22 Winchester- and running down the wounded bird, crasping it by the legs and smacking its head against a rock- how did he ever get away with a Federal crime like that I wonder?
As stated, it was very likely not a Bald Eagle, but a Golden Eagle which were not protected at that point in time. I don't believe they were protected until sometime in the '60s.