Good job they never shat in your cereal as you would never know.
Cats are funny but shrewd, Isuspect you will be hearing from that cat pretty soon. Its what cats do.
You think if you were floating and starving you would eat the sea, hasn't it got plankton in it. If you just drank pints and pints and pints of it surely you could filter out all those good nutrients. Of course you would have to enema-ise the water first to purify the salt out but that's a small price to pay for some shrimp