Answer:
Depending on if the body will float back up to the surface. The body will decay at a slower rate in the water than in open air- but a lot of it depends on the water temperature.
Typically, after a few days, the body will float back up to the surface of the water. Normally, birds and other assorted animals will start picking away. After a week or two, the corpse will be picked apart by assorted animals and the bones will sink down to the bottom.
