Green Turtle

Initially I drew two green turtles. I decided to remove the smaller one.

The contrast of the green turtle with its surrounding is quite high. By using two green turtles, this part of the illustration would get too much attention from the eye, which is sensitive to contrast.

Although objects, which are farther away from the eye, look smaller due to perspective distortion, the size of the turtle is not too big, since turtles can grow to be quite big.