Marine iguanas are said to be nine million years old, older than the islands themselves. They are a native genus with one species divided into seven subspecies. Descendants of the land iguanas inhabiting the Ecuadorean mainland, they probably floated out on naturally forming driftwood rafts to the Galapagos Isles. These iguanas, unique to the Galapagos, are herbivorous and feed mainly on algae.

Marine iguanas vary in size from head to tail; 60 centimeters for the smallest iguanas found on Genovesa Island to the larger ones (up to a meter in length) on Isabela Island. Their charcoal skin serves two important functions: one as camouflage from predatory animals and the other to better absorb heat from the sun to warm their reptilian blood.

There are officially two species in the native Genus, including another that was discovered on Fernandina Island. Land iguanas on the Galapagos Islands are yellow-orange to brown in color and differ from their distant cousins, the green iguanas (in South America and the Caribbean), in that they don’t fear man. There are two species found in the Galapagos:

• The yellow-orange variety (Conolophus subcristatus) found on Santa Cruz, Fernandina, Isabela and Plaza.
• The light- to dark-brown brown kind (Conolophus pallidus) on Santa Fe. These red-eyed natives can weigh up to six or seven kilograms for males and three kilograms for females.
• Their favorite food in the hot and dry periods are the pads, fruits and flowers of the opuntia cactus. They also feed on grass, centipedes and other seasonal vegetation.

The Black Turtle
Males are noticeably smaller than females: they have claws on their front flippers (to grasp onto the females´ shells during mating), long tails and a concave underside. Turtles reach sexual maturity when they are 20 to 25 years old. In November, group mating can be seen in the Tortuga Negra lagoon north of Santa Cruz. Egg-laying takes place every 2 to 3 years mostly between January and June. Eggs hatch after 2 months and the water temperature determines the sex of individuals. Sharks, crabs, and orcas are the main predators of the turtles. Turtles feed on algae (called Ulva) that grow on the roots of mangroves.

There are many theories about how tortoises reached the Galapagos, but no-one really knows. Only two islands in the world are inhabited by tortoises: Aldabra Island in the Seychelles and the Galapagos. They likely descended from Geochelone Chiliensis in Argentina, whose ancestral beginnings date back millions of years.

Male tortoises can weigh up to 250 kilograms and females up to 50 kilograms. There are currently around 6,500 tortoises on Isabela Island, more than on any of the other islands.

Common to the Galapagos, these natives (Spheniscus mendiculus) are close relatives of the Magellan penguins in Southern Chile, including penguins of the Falkland Islands and Antarctica. Brought to the Galapagos by the Humboldt Current, these flightless birds are excellent swimmers.

Their ‘wings’ having evolved into flippers, they are quite agile in ocean currents. On land they walk, hop or slide along rocky surfaces.

Adult birds are black on top and have brown undersides; they also have hooked beaks and small wings. Young birds are completely black. Males are normally larger than females.

Cormorants are usually seen along the tidelines airing out their tiny wings probably as a ritualistic habit pre-dating this evolutionary adaptation due to a lack of predators. There are only about a thousand of these rare birds found in the Galapagos today. They use their webbed feet to swim underwater and eat fish, eels and octopus.

Only found in the Galapagos, these large black-eyed birds are quite different from the Lava Gull. They have prominent red eye rings, a beautiful black and white spotted swallow-tail and light grey feathers on their backs. Swallow-tailed Gulls feed exclusively at night, the red eye-rings acting like a sonar system, helping the bird to find fish and squid. Characteristic white beak tips help chicks to see their parents at night, tapping on them to signal that they need feeding.

These gulls have peculiar calls ranging from screams to loud and rapid greeting calls. Other unique calls are thought to function similarly to echolocation.

Waved Albatrosses are found on the Island of Espanola, the only island where they reproduce. Close relatives of petrels and puffins, there are 13 species and an estimated population of 24,000.

Large wing-spans of 2.5 meters make them excellent gliders. They are migratory birds that return to the Galapagos in the dry season around mid-April, leaving in the middle of December to spend 6 months out in the open Pacific Ocean.

Also known as the ‘Vultures of the Sea’, these birds are designed to be out at sea having wingspans as large as Albatrosses.

Belonging to the Pelicaniformes order, they have distinctive characteristics that are specifically adapted to their habitat: reduced external nasal slits, and feathers that are not waterproof.

These birds are likely to steal prey from other birds, such as boobies, or pluck fish from the water with their long hooked beaks without actually getting their feathers wet.

Males usually prepare the nest prior to mating season. During courtship, the male inflates a red leathery pouch under his throat to attract females.

Slightly different to the Great Frigate, male birds have a purplish tinge on their black plumage while females have a black triangle on a white patch on their throats.

Magnificent Frigates are ‘inshore feeders’. They have long reproductive cycles, with only one egg being laid, and incubation lasts 55 days. Courtship behavior can be observed throughout the year.

It is a white feathered bird with 2 long distinctive feathers from its tail. There is also a black line that runs through its eyes. Juvenile birds don’t have the streaming tail feathers.

Tropicbirds are ‘offshore feeders’, feeding mainly on squid and fish by plunging into the water during the day.

Tropicbirds have differing reproductive cycles on South Plaza, Genovesa, and Daphne Island. Tropicbirds lay one red-brown spotted egg in rocks on cliff tops and reproduce in colonies.

There are 3 species endemic to the Galapagos: Blue-footed, Red-footed and the Nazca Booby. They are called ‘boobies’ probably because of their dart-like diving skills from a height of fifteen meters into the ocean when they spot fish. Boobies can also swim underwater when hunting for fish.

They live in colonies in a variety of habitats, and incubate their eggs with their webbed feet instead of an abdominal pouch.

There are two varieties of these, one of which is light- brown and the other white. They have distinctive bluish beaks and red webbed feet used for gripping branches in treetops where they build their nests.

Red-footed boobies lay one egg each reproductive cycle, and chick mortality rates can be very high depending on the availability of food. There are many red-footed boobies in the Galapagos despite this, boasting an impressive population of around 250,000.

Blue-footed boobies are ‘inshore’ feeders. They build their nests on the island shorelines and mark the nest sites with ‘sprays of ejecta’. Because there is more food inshore, they often lay 2-3 eggs.

Males are usually lighter than females, and plunge-dive for food. Mating rituals can be fun to watch with males dancing proudly, pointing their beaks to the sky and whistling loudly to attract a partner. Current population is estimated to be around 10,000, but there certainly could be more.

These are a new species of boobies that was officially discovered in 2001, which have conspicuous mask–like black markings around their eyes. They are heavier than the other boobies, and have orange-yellow colored beaks. Nazca boobies nest on the ground, similar to blue-footed boobies. The population is estimated to be at about 25.000.

These graceful birds are quite rare to the Galapagos, but can be found wading in the shallow waters behind the mangroves dotting the island coastlines.

Flamingoes can be found filter-feeding in brackish waters for microorganisms that they detect by sonar in their bills. Flamingoes feed for anywhere between seven and twelve hours a day.

Commonly found on Pinzon, Santiago and Isabela Islands, the Galapagos Hawk has also returned to the highlands on Santa Cruz.

They are usually dark brown with striped white tails. Juvenile birds are a lighter brown color. These hawks are extremely good hunters with sharp eyesight for catching prey like boobies, iguanas, snakes etc. They also scavenge dead animals and fish of all kinds.

Found on all the Islands in the archipelago, they were made famous by Darwin’s theory of Evolution. Belonging to a subfamily called Geospiznae, they are endemic only to the Galapagos and the Cocos Island to the north-east.

Originating from one species in the Caribbean, they all appear similar; however, to the trained eye, they are slightly different. There are 13 species native to the Galapagos Islands.

Sea lion colonies are a common sight in the archipelago. Males are huge and have a hump on their foreheads, while females have smooth foreheads. Males are usually dominant and mate with several females.

During the reproductive season, they usually mark their territories and protect their pups from wandering into the sea. Sea lions feed during the day and have been known to dive to depths of up to 100 meters in search of food.

The Humboldt Current brought this species to the Galapagos from the Southern hemisphere.

They are smaller than sea lions with big sad-looking eyes and a pointed nose. They hide from the hot sun under rocks during the day.