I think the ocean is draining to the right. Seascapes really show when you're not level. Try leveling in PP. The shark is very small, and without the title I would have never guessed it was there. However zooming or cropping would should a flat sea with a fin sticking out. I don't know if it would improve it any.
I'm sure you will get many folks who will tell you that in a shot like this it will improve on the image to have the horizon straight. This is just a simple rotate in any editing program. Is that really a shark or a dolphin?
I'm sure you've already heard about your crooked horizon...there's nothing here to draw me in, the title sounded exciting, and if you say so, ok, but I don't see a shark... is that black spot a fin? hard to tell really.
The wave doesn't have enough texture or pattern to carry this photo...a more defining subject could give this more interest and help balance the composition.
Where? You mean that tiny black spot in the centre? Ok, I'll take your word for it. Your shark is swimming downstream - straightening the horizon will slow him down a bit before he gets to the bathers and it'll even make your picture look better. It's also lacking in tonal range, saturation and contrast - you can tweak all of those in post processing.
Do you mean that dot centre shot? Shots like these have caused me to buy bigger and better cameras over the years! It's so frustrating when you can clearly see something but the camera optics refuse to do it justice.
I usually ended up reverting to the Mk1 Eyeball and just telling everyone about it.
I might have improved the shot if the horizon were level - sharks can't swim uphill!:)