Based on a True Story?

Im pretty sure that the story written by Willis O'Brien that the screenplay was based on,
was inspired from a famous essay entitled "Escudilla"
in the book 'A Sand Country Almanac' by Aldo Leopold published in 1949.
It was the true story of the last Grizzly bear in Arizona that was
killed in 1910.
The Bears name was"Old Bigfoot",who had lived on isolated Escudilla Mountain
( with an extinct volcanic crater at its top)
Each Spring Old Bigfoot came out from hibernation and came down from the mountain once a year and killed one cow a year for many years.
However no one had ever saw the bear but they usually saw its footprints and its handiwork.
Then in 1910 a government trapper was hired to kill the Grizzly which he did by
rigging a set-gun along a well worn bear path.The rifle was tied to a tree
with a line attached to the trigger and to some bait,
when the bear ate it,it shot itself
in the face and was killed.
It was the last Grizzly in Arizona.
Old Bigfoot's skull is now in the Smithsonian in Washington D.C.