A friend and I were in Palborough Mines getting his Kazham key, and we messed around a bit in the lower level where you drop off from the mithril refining machine. He fished one of these up with a composite fishing rod and a fly lure (might've been sabiki rig, since I gave him both for fun and giggles.)
Couldn't get a screenshot of it sadly but we might go back and do that for giggles again. ^^;