There's a SHARK in the Water!

Little VV Brown reference there! ^_^ I really like this song coz I see the lyrics as a girl trying to get the attention of a guy by faking fear of a Shark in the Water, hehehe I know I can be that silly sometimes x

This one you'll find in West Kessex Hills in a place called Viathan Lake. If you go to the vista in the center of the lake and take a good look around, you should be able to spot it. Now this Shark doesn't like to stay in one place, so the map might not be as accurate as I would like and it is hard to spot in the dark water :/ however, if you use your mouse, you should be able to find it easy.
Bare in mind the 2 Veteran Toxic Damoss near the vista but they shouldn't bother you if you don't get too close.

http://wiki.guildwars2.com/wiki/Juvenile_Shark