Regarding saltwater sharks and aggression, I believe the Bull Shark is widely considered to be the most aggressive, with the Mako not far behind.
actually bull sharks are teh most aggressive shark, tehy have higher testosterone levels then any of the others and are responsible for most of the attacksgreat white are not as aggressive as tiger! GW are just big and curious, and they try to eat every thing rather than attack everything!
ARGH!!!!!!! how could this so-called harmful snakeheads destorying American waters?????I have no idea. But I too, would like to say the snake head of all varieties. (giant, and otherwise). Last week on a National Geographics series (I think, Hooked) featured the snakehead and how the foreign introduction of these fish was destroying American waters.