The Galápagos green turtle is the only sea turtle that breeds in the archipelago, with thousands of individuals present year-round. Snorkelling encounters at Gardner Bay (Española), Post Office Bay (Floreana) and Tortuga Bay (Santa Cruz) are reliable and intimate — turtles graze sea grasses just metres from swimmers. Nesting season peaks January-March, and liveaboard cruises add hawksbill and olive ridley sightings in the northern and western islands. Accessible only via regulated cruise or land-based itineraries with national park permits.