
The squirrel was already dead; it didn't move at any point. I don't know if the seagull killed the squirrel or if it found the squirrel already dead. I did see the seagull dipping the squirrel carcass into the ocean.
I honestly didn't think the seagull could eat something that big but

And yes it did all go down as can be seen here

Even more surprising to me was that the seagull was able to fly away with all that extra weight. But it did.