So, his family called the newspaper (probably the Daily Herald). They sent a reporter up Provo Canyon to photograph it. Locals of the time speculated it was an old bull that had been forced out of its territory by a younger male and that it had wandered south from the Yellowstone area.

I just Googled whether moose were native to Utah and learned that while they were absent in pioneer times, they eventually expanded their range southward from Wyoming. The first moose seen in Utah was in 1906.