Oh man, the thumbnail made me very excited for this and it did not disappoint. The graphics are great and a good fit. The theme is inherently spooky, too. Irrational fear of sharks in games is something I picked up from the original Tomb Raider and Banjo-Kazooie games.
Were logs supposed to deal damage to you, too? It seemed you could get damaged only by bombs and life rings (?). And really, once you got a few speed ups, the shark seemed irrelevant. I was really playing against the obstacles. I got just over 700 points before I realized the shark was never coming back and I lost to obstacles instead of being eaten. For a game about running from a shark, I think it could stand to benefit from more shark. Maybe it gets faster or never can be more X units away?
Overall, cool game. I enjoyed my time with it. Well done!