Despite a few of them often seen as friendly and approachable, turtles often snap and attack when they feel threatened. If you happen to come close to one while swimming, don't get too close or obstruct its way. Remember you should not feed turtles anything that can't be found in the sea. Tourists are often seen feeding bread to turtles as they are unaware of the harmful effects this might have an overall ecosystem, including disrupting and potentially harming the turtle's digestive system. Turtles, depending on their environment and type, can either be herbivores, omnivores or carnivores and will eat anything from algae to jellyfish!