However, not all sea creatures are venomous. Dolphins are not fish but, like whales, are warm-blooded mammals. They communicate with each other using different sounds. They are very intelligent and can learn many trick in can learn many tricks in captivity. The same cannot be said of sea turtles. They seem creatres of instinct. When it is time for the female to lay her egg, she swims to the shore, dige a hole, lays the eggs and covers them with sand. When the baby turtles hatch, they find their way to the sea and swim away. Many years later, as adults, the females returns to the very same place to lay their own eggs! Under the sea, where fish swim so free, that,s the place you might want to be!