This poor bug landed on the deck railing, struggling and writhing to get these mites off. At least I think they're mites. I tried to help, but they didn't budge. I think it's some kind of leaf cutter type beetle, but it was hard to tell. It flew off eventually, but I think it was doomed. Shot with the OM 90mm f2 macro.
Update - it's a carrion beetle and the mites it carries eat competitive fly larva (maggots) and fly eggs on a corpse the beetle turns up at late as usual. It's a beneficial parasitic relationship, not a destructive one.