Inaki Relanzon / Hawksbill turtle (Eretmochelys imbricata) swimming underwater, Nosy Be, North Madagascar.

Doug Perrine / Green sea turtle (Chelonia mydas) being cleaned of algae by Yellow tangs / surgeonfish (Zebrasoma flavescens), Puako, Kona, Hawaii, USA, June, Endangered species

Jordi Chias / Green Turtle, (Chelonia mydas), Swimming over volcanic sandy bottom, Armenime cove, South Tenerife coast, Canary Islands, Spain, Atlantic Ocean, May 2011, Commended in Wildlife Photographer of the Yea...

Onne van der Wal / Green turtle (Chelonia mydas) swimming over sea grass, Grenadines, Caribbean, February 2010.

Wild Wonders of Europe / Lundgre / Loggerhead turtle (Caretta caretta) with a shoal of Pilot fish (Naucrates ductor) Pico, Azores, Portugal, June 2009

Juergen Freund / Baby green turtle (Chelonia mydas) hatchling in the shallows of the beach, swimming out to sea. Anano Island, Wakatobi, South Sulawesi, Indonesia.

Doug Perrine / Green sea turtle (Chelonia mydas) cleaned of algae by Yellow tangs / surgeonfish (Zebrasoma flavescens), Puako, Kona, Hawaii, USA, June, Endangered species

Jordi Chias / Juvenile green turtle (Chelonia mydas) reflected in the surface of the window with Snell's window affect, Fakarava atoll inside lagoon at sunset, Tuamotu archipelago, French Polynesia; Pacific Ocean

Jordi Chias / Green turtle (Chelonia mydas) from underneath~swimming through the surface, Mayotte Island, Comores, Indian Ocean.

Jordi Chias / Juvenile Green turtle (Chelonia mydas) swimming near the surface, split level view, Fakarava atoll lagoon, Tuamotu Archipelago, French Polynesia, Pacific Ocean.

Graham Eaton / Leatherback Turtle Hatchling (Dermochelys coriacea) crossing a beach towards the sea at sunrise, Cayenne, French Guiana, July

Doug Perrine / Green sea turtle (Chelonia mydas) being cleaned by yellow tangs (Zebrasoma flavescens) at a cleaning station where the turtles are groomed by the fish in a mutualistic, symbiotic relationship, Puako,...