Simplify the following text for a Grade 7 native English-speaking person.
Original: Six species of sea turtles come to the reef to breed â `` the green sea turtle , leatherback sea turtle , hawksbill turtle , loggerhead sea turtle , flatback turtle , and the olive ridley .
Simplified: Six species of sea turtles come to the reef to breed . These are the green sea turtle , leatherback sea turtle , hawksbill turtle , loggerhead sea turtle , flatback turtle , and the olive ridley .