Anyone? ! the green turtle is the largest hard-shell turtle in the world. they are named for the color of their body fat. green turtles often weigh as much as 300 pounds and grow to be almost 4 feet in length. in the united states, they are protected by the endangered species act. 1. of the six species of sea turtles that are present in australian waters, 3 species are rarely encountered. what fraction of the species are rarely encountered?