A bad donut?
Was it carrying a picnic basket?

Just kidding.

Lot's of people out there swear by what they've seen so I can't discount it but I've never seen one or signs of one. If they exist then they have to be very low in population with a vast territorial range so there'd be very few per X miles and they'd have to take care of their own when deceased. Otherwise we'd have found one by now. But then 've only surprised a bear once in all of the fishing and hiking I've done and there's lot's of bears.