[EBB Sightings] Eared Grebe with Catch

Does anyone know what it caught?  I see Grebes and Snowy's catch these regularly in the shallows presumably near bottom rocks.  Their defense is to curl into a loop, grabbing their own tail? It makes subduing them quite difficult, often taking many minutes to undo.

http://www.pbase.com/image/119702874

My guess is some kind of eel.