come on guys don't be stupid, it is an internet hoax.
The only picture used on ALL facebook groups&forums against this is the dog at the start of the movie who have some how managed to get a hook in his mouth.

There is no such thing as dogs beeing used as shark bait.
Why in the world would they need to?
To fetch a shark you just throw bloody meat in the ocean, wait for it to show up and then harpoon it..
You dont carry a dog on a boat and throw it in the ocean.