Did you happen to notice if these 'seals' (sea lions) had opposable thumbs. If they are evolving and have developed opposable thumbs, we are in a buttload o' trouble. Think of what that would bring. Not only could they steal the mac off your hook, but they might tie your line to another yakker. It would be chaos.
More likely that they were dragging the hoops across a stretch of bottom with some loose rock and your net scooped some up.