Marine iguanas in the Galapagos are the only one of their kind; adept at living on land and at sea. The endemic reptiles dive alongside those swimming and snorkeling, performing sharp turns and rolls in the shallow water while foraging for food along the ocean floor.
On land, the spiny iguana rests on the rocky, volcanic shores of islands including Isabela, North Seymour, Bartholomew, and Santa Fe. They dive for short periods of time and need time-out of the water to warm themselves before returning to the cool Galapagos waters.
Found throughout the archipelago, one island where nesting sites on beaches are common in Santa Cruz. After hatching, young marine iguanas migrate to shallow waters and rocky cliffs to feed and grow before they start swimming. Visitors to Puerto Ayora are asked to watch where they tread within the town, as one route from the hatching grounds to the feeding grounds runs straight down the main street.
Marine iguanas change color during mating season, turning brilliant shades of red, orange, and green. The largest marine iguanas are found on Isabela Island, where adults can reach lengths of up to 3 ft. and can weigh as much as 30 pounds.
Marine iguanas have special glands that help them get rid of excess salt absorbed from the ocean when swimming. The reptiles sneeze away salt in surprising outbursts, often covering the top of their heads in a white crust until diving back into the sea.