Good account from the photographer - see also www.theguardian.com - who's line about being an Army photographer is classic.
As for the bison, really hard to overstate: they are EXTREMELY dangerous, easily riled, fast, and can turn on a dime. The bearded guy seemed to be doing about what he could. The buffalo appeared to have staked out that table, perhaps as a feeding area? Anyway, when in places like Yellowstone it helps for perspective's sake to bear in mind you've crossed over the wall between your world and theirs. Think of it kind of like Jurassic Park. Or Florida.
Nobody said enablers, bootlickers, and lackeys won't be allowed to give their beaks a taste. For a price. Let's call it a "tip." It's actually okay with SCOTUS, if you time it right.