Barliman calls this "An embarrassment to cats, everywhere."
One of Barliman's commenters, John H., saves feline dignity: "I imagine the cat telling the gull, 'If you want it, it’s yours. This new food tastes horrible!'"
Another explanation: the master species is allowing the bird-brained one to fatten itself, in order to serve as a more bountiful feast tomorrow.
[Added] Belinda, via email:
Everyone knows cats can't be bothered unless the result outweighs the comfort of the current napping position. And we humans will refill that bowl tomorrow. Smart cat.
[Added2] MK reminds us this isn't the first time the terrorists have been caught on camera. Remember this al Qaedagull?