This is freight / storage damage and will pop back out. Polyethylene has molded memory and typically can be returned to the original shape.
Easy Dent Removal
Kayaks can be dented by various means, no need to worry, they are simple to remove. Improper storage, cart use, freight/transport, too much pressure on tie-down straps all can cause a dent in a kayak. We have the solution. Watch Jacques Bernier in the video linked below. Jacques explains the simple procedure that, as you will see, can remove even a nasty dent in the side rail of a kayak.
Dent Removal Video:
http://www.youtube.com/watch?v=OpuIJzMotDgSuccess Story: