Exactly. I was thinking they would explode like Bill Clinton by the time they got up to one thousand feet.
It seems logical that even though they usually stay at the bottom of the sea (real bottom feeders there), they must rise to the surface or to a depth where they could get trapped in a fisherman's net. I doubt fish feed on them and don't know if there are any natural predators. Kind of creepy things but look somewhat like crabs.