i went to sooner today & started out at the cold side inlet channel & where the big orange buoys are i went to tie up & saw a bunch of catfish under the buoys. the bite was so good i couldn't even drink my coffee. to make a long story short i caught a bunch of channel's & a few that i think they call mississippi whites. i noticed when i filleted them they had more shells & grass in them than anything else. i've attached a pic, what exactly is it & what are they all about. thanks.