Wildlife of the Galápagos
Close-Up Animal Encounters
Birds that have lost the ability to fly. Reptiles that look like little knights in chain mail. Sea “dragons” that spit salt instead of fire. And giants that walk among smoldering volcanoes.
The abundance of wonderfully odd and strangely beautiful wildlife makes the Galápagos Islands the perfect destination for nature and animal lovers. And making a trip to the archipelago even more fascinating is that there is no other place on the planet where you can get as up-close and personal with such creatures. That’s because, in the Galápagos, the fauna has no natural fear of humans.
Because the Galápagos Islands were never connected to the mainland, the ancestors of every native animal species had to find a way here from somewhere else. Flotation rafts of natural vegetation, winds, and ocean currents all provided passage. Boobies, cormorants, giant tortoises, land iguanas, and pelicans arrived from South America. Fur sea lions and penguins rode the Humboldt Current north from the Antarctic thousands of years ago. Darwin’s finches and pink flamingos came in from the Caribbean. Some land mammals even waited to hitch a ride on human vessels.
Today, as with the plants of the Galápagos, many wildlife species are struggling with the challenges that come with living in the islands. But conservation efforts have made astounding turnabouts in what were once thought to be insurmountable obstacles to the continuance of some species. Many thought to be at the brink of extinction now have significant population numbers. And tourism continues to play a big part in preserving the wildlife of the Galápagos.
Surrounded by thousands of miles of open ocean, the Galápagos are a hotbed of seabird activity. Blue- and red-footed boobies, flightless cormorants, and a northern penguin will delight you with their incongruities and unusual appearances — and some fancy dance steps.
The islands’ land birds, too, play a unique role in the biota of the archipelago. For it was the little birds now known as “Darwin’s finches” that helped to form Charles Darwin’s theory of evolution — a concept that rocked the world.
In addition to those that prefer the sea and those that inhabit the land are the birds that have taken to the coasts. These shoreline denizens have found a way to intelligently adapt to the in-between niche overlooked by their water and rock-and-soil counterparts.
Greater Flamingo (Phoenicopterus ruber)
With their pink to vermilion plumage, long legs, and statuesque height, greater flamingos are striking to look at and instantly recognizable.
Standing at four feet to almost five feet tall, the greater flamingo’s coloration varies with the amount of carotinoid pigment consumed in its diet of crustaceans and microorganisms filtered out of the saline waters of the coastal lagoons where it typically feeds.
The flamingo’s bill is pink with a black tip and curved downward; when feeding, it is inverted and used as a filter. Its legs and feet are pink, gray, or flesh-colored. The young are much paler.
Nests are constructed out of mud and shaped like flat cones, seven to ten inches high. Both adults incubate a single egg for about thirty days. Fledging takes sixty-five to ninety days.
The call of the greater flamingos is a soft, goose-like honk. They are easily disturbed and will take flight if approached noisily. The birds may live to be eighteen to twenty-four years old.
The greater flamingo population in the Galápagos is thought to number less than five hundred individuals.
Where to see them: On Floreana, Isabela, Rábida, Santa Cruz, and Santiago Islands.
Yellow-Crowned Night Heron (Nyctanassa violacea)
As its name suggests, this medium-sized heron is mainly active at night when it goes hunting for beetles, locusts, other insects, centipedes, crabs, and scorpions. It has a distinctive yellow crown with long, cream-colored plumes. Its head is mainly black but has a broad, white stripe running back from the underside of its large, yellow-orange eyes. Its body is predominantly gray, with some brown and black feathers.
Yellow-crowned night herons breed in single pairs and build nests year-round in mangroves or under rocks. A clutch of two to four, blue-green eggs is incubated for about twenty-four days by both parents. Fledging occurs in four weeks.
Where to see them: Yellow-crowned night herons are common and widespread in the islands, though by day individuals are usually found in the shade of shrubs or rocks or in shaded areas along the coasts of the islands.
Probably the most famous of the Galápagos land birds are Darwin’s finches, so named in the 1930s because of their importance to Charles Darwin’s theories of evolution. Darwin was fascinated not only with the diversity of the thirteen species but by how quickly they evolved from a common ancestor to adapt to the type of food supply on each of their islands — and even within an island based on vegetation zone. These adaptations are mainly manifested in the shape and size of their beaks. Two species (the mangrove and the woodpecker finch) even use tools — twigs or cactus spines — to extract insect larvae from holes in dead tree branches.
All thirteen species of this sparrow-sized bird are colored mottled gray, brown, black, or olive. Because of these superficial similarities, they are often hard to distinguish from one another in the field.
There are four species of ground finches, three tree finches, two cactus finches, a mangrove finch, a vegetarian finch, a woodpecker finch, and a warbler finch (which may be split into two species: one found mainly in the lowlands and the other mostly in the highlands).
During courtship, a male will build several side-entrance nests, hoping that one of them will please a female. After examining a male’s construction skills and selecting her mate, the female may want yet another “house.” So the two will build one more nest. In a further demonstration of his affections, the male feeds the female prior to egg laying and after incubation.
The thirteen’s species of Darwin’s finches are:
- Cactus Finch (Geospiza scandens)
- Large Cactus Finch (Geospiza conirostris)
- Large Ground Finch (Geospiza magnirostris)
- Large Tree Finch (Camarhynchus psittacula)
- Mangrove Finch (Cactospiza heliobates)
- Medium Ground Finch (Geospiza fortis)
- Medium Tree Finch (Camarhynchus pauper)
- Sharp-Beaked Ground Finch (Geospiza nebulosa [formerly Geospiza difficilis])
- Small Ground Finch (Geospiza fuliginosa)
- Small Tree Finch (Camarhynchus parvulus)
- Vegetarian Finch (Platyspiza crassirostris)
- Warbler Finch (Certhidea olivacea)
- Woodpecker Finch (Cactospiza pallidus)
Where to see them: Darwin’s finches can be found just about everywhere in the Galápagos. Although they may have originally evolved in isolation, the different species are now often together in various combinations on the islands, with a few exceptions: The mangrove finch once was found in dense mangrove swamps on Fernandina and Isabela. However, it has now disappeared from Fernandina, and less than one hundred of the birds are thought to remain in three tiny mangrove patches on Isabela. Of the islands with visitor stops, Española and Genovesa are the only ones with the large cactus finch.
The Santa Cruz Highlands are a good place to spot tree finches as well as the woodpecker finch.
Galápagos Hawk (Buteo galapagoensis)
The endemic Galápagos hawk is known for its fearlessness. The birds will often investigate visitors, approaching within a few yards. They have no natural enemies, but humans have taken their toll. Hunters caused their extinction on several islands, including Baltra, Daphne, Floreana, and San Cristóbal. They were extinct on Santa Cruz for a time, but have since returned to that island’s highlands. There are thought to be only 120 to 150 pairs and about eight hundred individuals remaining in the Galápagos.
Galápagos hawks are the only raptors that breed in the islands. They are dark brown, with yellow legs, feet, and ceres (an enlarged, fleshy area at the base of the bill), and they have much broader wings than similarly sized seabirds. The female is generally larger than the male, and the young are lighter in color than the adults and heavily mottled.
With sharp eyesight, the Galápagos hawk — both a predator and a scavenger — can detect its prey from a great distance. It will eat live boobies, finches, flycatchers, iguanas, lizards, and snakes; and dead fish, marine iguanas, seabirds, and sea lions.
Breeding occurs year-round, but is most frequent from May to July. Nests are made in trees or on rocky outcrops; and at each breeding attempt, the nests grow larger with new twigs added. Up to three young may be raised at a time. The birds practice what’s termed cooperative polyandry, where a single female will mate with as many as four males, and all will help in caring for the eggs and young.
Where to see them: Galápagos hawks may be seen on Bartolomé, Española, Fernandina, Isabela, Santa Fé, Santiago, and South Plaza Islands.
Short-Eared Owl (Asio flammeus galapagoensis)
With its long wings and low, flapping flight, the short-eared owl may be mistaken for the Galápagos hawk. Colored dark brown above and paler underneath, the bird — in contrast — has some lighter streaking above with dark markings below. Its dark facial disc emphasizes its yellow eyes. The bill is dark, and the legs are feathered. The short ear tufts may be difficult to see.
The short-eared owl feeds mainly on small birds and particularly preys on mice, rates, storm petrels, and some larger insects.
The owl nests on open ground on all the major islands, with the exception of Fernandina. It prefers the highlands. Three or four eggs are typically laid, although normally only two chicks survive to fledging.
Where to see them: Short-eared owls are most likely to be seen hunting and in flight. They are present on almost all of the major islands. Good opportunities to see them occur on Floreana, Genovesa, Isabela, San Cristóbal, or in the Santa Cruz Highlands.
Blue-Footed Booby (Sula nebouxii)
With its bright blue feet, the appropriately named blue-footed booby is perhaps the most famous of the Galápagos birds and is often the first type of booby most visitors see. Large colonies live on Española and Seymour and are present throughout the year.
Blue-footed boobies have brown plumage above, white below, and darker brown wings. The young are completely brown. The female is slighter larger than the male, appears to have a larger eye pupil, and generally has darker blue feet. During courtship, a female will honk, while the male emits a whistle.
Their diet is almost exclusively made up of fish, which they catch by plunge diving. They often start their dives from fifty feet or more in the air and accelerate as they fly towards the water, folding their wings in to become arrow-like. Because they hit the water with such force, they have developed air sacs in the skull that serve as built-in shock absorbers. Blue-footed boobies have proportionally longer tails than Nazca or red-footed boobies, which act as rudders and allow them to make these bullet-like dives into less than two feet of water. Thus, they can feed closer to shore.
These boobies nest in dispersed colonies close to the sea. During the courtship ritual, each blue foot is lifted alternately in a dance, almost as if they are showing off enormous clown shoes. A pair will then “skypoint,” a posture in which they point their tails and beaks vertically upwards, half opening their wings and honking or whistling according to their sex. Breeding takes place at any time of the year when the food supply is abundant. Up to three eggs are laid in the nest — which is actually a scrape on the ground surrounded by guano — and incubated by both parents for about forty-two days.
The chicks are covered with fluffy, white down that can make them look larger than their parents. In a good year, all three offspring may survive; otherwise, the strongest one or two will outcompete the weakest, which subsequently dies of starvation. The young fledge at 102 days and start breeding after three to four years.
It is estimated that there are about twenty thousand pairs in the Galápagos, which is approximately half of the world’s population. They live fifteen to twenty years.
Where to see them: Blue-footed boobies are found throughout the islands and breed on all the islands south of the Equator, though on occasion they also breed on Genovesa. There are large colonies on Española and Seymour.
Nazca Booby (Sula granti)
The Nazca booby is the largest of the three species of booby found in the Galápagos Islands. It measures three feet in length and has a wingspan of five to six feet. The adult is almost entirely white with a black tail and black ends to the primary feathers on the wing. The bill is yellow (male) to pale yellow (female). The skin at the base of the bill is black, thus giving the bird a “masked” appearance. Its feet are a dull, gray-green. Male and female calls have different sounds: The smaller males whistle, while the females utter a loud quack. A young Nazca booby is mostly brown on top and pale underneath.
As with the other boobies, the Nazca booby feeds almost entirely on fish, which it catches by plunge diving. Unlike the blue-footed booby, however, the Nazca booby fishes farther offshore and so is less frequently observed fishing.
Breeding for this bird, unlike with the other boobies, takes place on an annual cycle that varies from island to island. The courtship ritual is almost the same as for the blue-footed booby, but it is far less elaborate. Two eggs are laid in a shallow depression on the ground that is surrounded by a circle of pebbles or other debris, but even in a good year with plenty of food the older sibling will eject the younger from the nest so that only one survives. Sibling murder ensures that the parents never have to feed two chicks for any length of time and allows them to raise young as frequently as possible. Because they are large birds, they often nest near cliff tops in order to take advantage of winds during takeoff.
On Genovesa Island, the Nazca boobies arrive in May; followed by courtship, mating, and nest building. Eggs are laid from August to November. Most of the young have fledged by February, and the colony goes out to sea until May. On Española, however, the colony is present from September to May, with egg laying occurring from November to February.
There are about twenty-five thousand Nazca boobies in the Galápagos.
Where to see them: You may find Nazca boobies at sea and at the breeding colonies on the steep slopes of Española and Genovesa. You may also see them on San Cristóbal.
Red-Footed Booby (Sula sula)
The red-footed booby is the smallest of the Galápagos boobies, with a length of 2.5 feet and a 4.5-foot wingspan. It is easily identified by its bright-red feet and blue bill with a red base. The red-footed booby has two distinct plumage phases. In the brown phase, which is by far the commonest in the Galápagos, the bird is almost entirely colored a medium brown, with red feet and legs. In the white phase, the red-footed booby is almost totally white, apart from the tips of the primary feathers and the tail, which are black. An intermediate plumage stage can also occur. The females make a quacking sound, which is higher pitched and more nasal than the sound emitted by males.
The red-footed booby is the most numerous of the Galápagos boobies, but it is also the least frequently seen. That’s because it is found only on the outlying islands, such as Genovesa, where a sizable colony exists, estimated at 140,000 pairs. Semi-nocturnal, the red-footed booby feeds far out to sea, avoiding competition with the blue-footed booby (which feeds closer inshore) and the Nazca booby (which feeds in the intermediate zone).
The breeding cycle of the red-footed booby can last for twelve months or more. Courtship, which is performed in trees, involves head shaking and “skypointing,” but it is not as dramatic as with the blue-footed booby. A single egg is laid in a rudimentary nest in a tree, as opposed to the guano-ringed scrapes or shallow depressions on the ground of the other boobies. The egg is incubated by both parents for forty-five days. The chick fledges after 130 days, but it is still dependent upon the adults for ninety more days.
Where to see them: You may see red-footed boobies at sea; and where the population breeds on Genovesa, San Cristóbal, and Seymour Islands.
Flightless Cormorant (Nannopterum harrisi)
Aptly named due to its complete inability to fly, the rare, endemic flightless cormorant is the only cormorant found in the Galápagos Islands. Its wings are no more than vestigial appendages that appear to serve no useful purpose.
This large, thirty-seven-inch-long, six- to eleven-pound, dark brown to black bird is unmistakable when seen hanging its stubby wings out to dry after coming ashore. They have large, black, webbed feet with very short but sturdy, black legs. When in the water, their bodies are almost entirely submerged with just their snake-like heads and necks visible.
The flightless cormorant has brilliant, turquoise eyes and a long bill with a pronounced hook at the tip. The males are noticeably larger than the females.
These birds feed on eels, small fish, and octopuses, which they catch close to shore. They dive from the surface with a jackknife-like movement and use their large, powerful webbed feet to pursue prey.
Flightless cormorants nest in small colonies close to shore and have an elaborate courtship ritual, which normally starts in the water with a “dance.” They hold their necks in an S shape in a pose known as “snake necking.” The birds then swim back and forth past each other. The male will eventually lead the female ashore, where he turns his back to her and again forms an S with his neck. The dance is continued on land; and then, as part of the courtship process, a large, bulky nest made of seaweed and other flotsam is presented to the female by the male.
Breeding takes place year-round, though most eggs are laid between May and October. Normally, three eggs are laid, but typically only one chick survives. Incubation by both parents takes about thirty-five days, and initially both parents feed the young. If, however, the food supply is good, the female may leave and mate with another male, while the first male continues to look after and feed the young for up to nine months.
Today, flightless cormorants are vulnerable. Only about six hundred to eight hundred pairs are estimated to live on the islands of Fernandina and Isabela.
Where to see them: Flightless cormorants are found only on Fernandina and northern and western Isabela.
Frigatebirds: Magnificent (Fregata magnificens) and Great (Fregata minor)
Frigatebirds are often called pajaro pirata in Spanish, or the “pirate birds.” They eat a wide range of foods, including small crustaceans, fish, and newly hatched Galápagos green turtles, which they pick up off the beach almost as soon as they emerge from the nest. Frigatebirds will frequently chase blue-footed boobies or red-billed tropicbirds and force them to disgorge their recent catches, often by holding their tail feathers and shaking them until they regurgitate. The frigatebird will then catch the bolus before it hits the water.
In their defense, however, frigatebirds have a very small preening gland and are therefore not able to secrete enough oils to waterproof their feathers. So unlike other birds, they cannot dive underwater to catch prey and must snatch it from the surface with their hooked beaks or take it from other birds.
With their black bodies; long, scimitar-shaped wings; and forked tails, frigatebirds have been likened to sinister kites hanging in the wind. They are able to hold a single position in the sky as if suspended from invisible strings. From such an airy perch, they harry other birds. These large, almost-four-foot-long, elegant, streamlined seabirds have wingspans of nearly eight feet and weigh from one to four pounds — the largest wingspan to weight ratio of any bird on the planet.
There are two different species of frigatebirds in the Galápagos. Distinguishing the all-black males is difficult. The magnificent frigatebird is slightly larger than the great frigatebird — a difference that is almost impossible to detect in the field. Also, the male magnificent has a metallic-purplish sheen to its back, whereas the male great frigatebird has a greenish hue.
The females are easier to set apart. Magnificent females have a thin, blue-green eye-ring, and the white feathers of their abdomens and breasts extend up to their throats. In great females, the white feathers reach up to their chins; and they have reddish eye-rings. If you can identify the females, of course, you can assume that their mates are of the same species. Immature magnificent frigatebirds have a white head, neck, and breast. Juvenile great frigatebirds have rust-colored patches on their heads and breasts.
As with so many Galápagos seabirds, the frigatebirds’ courtship display is spectacular. It is the females who do the conspicuous searching out and selecting of their mates. The males have a scarlet throat pouch, which is only visible during the breeding season. During courtship, several males will sit together in a tree and inflate their throat pouches to football-sized proportions. They then display them skyward by lifting their heads in an attempt to attract a female passing overhead. The male will call a shrill, ululating trill.
Once a pair is formed, they will then engage in an acrobatic aerial exercise. The two will build an insubstantial nest of twigs in a low tree or shrub close to shore, often using sticks stolen from other frigatebirds’ nests.
A single egg is laid, which is incubated by both parents for forty-two days for the magnificent frigatebird and fifty-five days for the great frigatebird. The magnificent frigatebird’s young will fledge after ninety days but are often looked after for up to six months by the parents. A great frigatebird will look after its offspring for up to eighteen months.
Where to see them: Although there are colonies on many of the islands, Seymour has a constantly active, magnificent frigatebird colony and affords some of the best viewing opportunities. Great frigatebirds tend to go farther out to sea to feed and are found more often on the outer islands, such as Genovesa.
Galápagos Penguin (Sphensicus mendiculus)
Penguins are most often associated with the colder regions of the Southern Hemisphere, so finding one at the Equator can seem surprising. The cool Humboldt Current in the Galápagos, however, flowing from Antarctica along the South American coast, enables this penguin — the most northerly in the world — to live here. It is the only one of the eighteen penguin species to occur north of the Equator and nest entirely within the tropics.
The Galápagos penguin is one of the smallest penguins in the world; it is only about nineteen inches in length and fourteen inches tall when standing upright. Adults have black wings and upper parts with white underneath. There is an irregular dark band along the flanks and across the upper breast. The head is black with a white eye-stripe extending around to the throat. The bill has a dark upper mandible; while the lower mandible has a dark tip and pale mid-section, gradually turning to pale orange at the base.
Galápagos penguins breed at any time of the year when the food supply is abundant, but most commonly from May to January when the water temperature is 74 degrees Fahrenheit or below. They choose a mate for life and nest in small colonies in holes or crevices in the rocks close to shore. The normal clutch is two eggs, of which only one chick generally survives. Incubation takes about forty days and is performed by both parents, who look after the chick for sixty days more before it is able to fend for itself. After becoming independent, the chick may stay with its parents for a longer period of time.
Feeding mainly on small fish and crustaceans, including herring, mullet, and piquitingas, Galápagos penguins sleep on land and look for food during the day, returning to shore between 4:00 and 6:30 p.m. Penguins’ clumsiness on land belies their skill and speed underwater. Their wings evolved for use as fins, and one of the best ways to appreciate their agility is to snorkel with them. A penguin underwater is amazingly quick — they can reach speeds of up to twenty-five miles per hour.
Where to see them: Galápagos penguins are found mainly on Fernandina and the northern and western sides of Isabela, although they do breed in small numbers on Bartolomé, Floreana, and possibly on Santiago. They are seen occasionally elsewhere in the islands, such as on Sombrero Chino.
Lava Gull (Larus fuliginosus)
Thought to be the most rare gull in the world, the endemic lava gull is found only in the Galápagos. Though few in number (about four hundred pairs), it is widely distributed around the coasts of the archipelago. The adult is dark gray, with an almost black head and upper neck, which forms a “hood.” Its white eye-ring contrasts sharply with this hood, as does its scarlet gape (inside of its mouth). Its eyelids are red. The young have brown in their plumage.
The lava gull is a highly territorial species and will attack anything that comes near its nesting sites, using its feet to hit what it thinks is an aggressor. The long, loud, “laughing” call of the lava gull often helps to pinpoint this dusky-colored bird among the lava rocks. The call is used as a threat display to members of its own species and denotes territorial ownership.
Lava gulls are solitary nesters, laying two, olive-green-and-speckled-brown eggs in a scrape near a lagoon, on a sandy beach, or on a rock spit.
Where to find them: Lava gulls are found on the coastal areas of the central islands and on Genovesa. The densest populations are around the more populated ports, where there is always an abundance of fish and some waste in the harbor, and their propensity for scavenging pays off.
Waved Albatross (Phoebastria irrorata)
One of the world’s most magnificent and mysterious birds is the waved albatross, endemic to the Galápagos, which spends years at sea without ever touching land. It is the largest bird that breeds in the islands, with a wingspan reaching up to eight feet. It averages three feet in length and six to eight pounds in weight. Apart from a few pairs which breed on Isla de la Plata off the coast of Ecuador, the waved albatross is only found on Española Island (with another recent possibility of Genovesa). There are estimated to be about twelve thousand breeding pairs, which translates to about thirty to thirty-five thousand individuals.
The upper body of the waved albatross, as well as the wings and tail, are dark brown; the underside is light brown, becoming paler at the breast with gray, wavy barring — hence its name. It has a creamy-colored head and nape, and its neck is off-white. The large bill is yellow with dark tips. Females are noticeably smaller than males, and the young lack the yellow bill.
The waved albatross engages in one of the most spectacular, ritualized courtship “dances” of any bird, which tends to take place at the end of the preceding breeding season. October is the busiest month, but you may see it anytime that a colony is occupied. The display involves a perfectly choreographed routine of up to twenty minutes of bowing, swaying and freezing, bill circling and clacking, and a cow-like “moo” with bills positioned vertically.
A single egg is laid on the bare ground between mid-April and late June. Incubation by both parents takes about sixty days. While the reason is unknown, parents roll the egg around every day, despite the risk of its cracking. The young are fed with pre-digested oil manufactured by the parents’ stomachs from fish and squid, the principal constituents of their diets. Fledging takes place about 170 days after hatching. Adults and young leave the island in December. When a young bird leaves, it does not return to land for four or five years. From January to March, all the birds remain at sea.
In general, a waved albatross lives a long life, about forty to fifty years. However, because it has a low reproductive rate and breeds in basically one location, the waved albatross is a vulnerable species.
Where to see them: Waved albatrosses are easily recognized in the air by their size and long, straight wings. On water, they are often in large groups (called rafts). They may be seen at sea in the southern half of the archipelago or on Española, where you may spot them flinging themselves off the cliff to fish in an area appropriately nicknamed the “Albatross Airport.”
In very recent years, small groups of waved albatrosses have been spotted on Genovesa.
Cetaceans, a scientific order of entirely aquatic mammals, are divided into two major groups: baleen whales and toothed whales. Baleen whales tend to be larger, and they feed on plankton and other small marine animals that they sieve from the water using their “baleen,” or triangular pieces of whalebone that hang down from their upper jaws in transverse plates. Toothed whales — which include the orca, sperm whale, and all the dolphins and porpoises — feed on fish, squid, other cetaceans, and marine mammals, such as sea lions and fur seals.
About twenty-four species of whales and dolphins have been recorded in the Galápagos, and it is almost certain that other species are present. Identification, however, is often difficult and sometimes impossible. Most visitors will see at least one species, the bottlenose dolphin.
But if you’re lucky — and patient — others may reveal themselves to you.
Blue Whale (Balaenoptera musculus)
The blue whale is the largest animal on the planet, and it regularly visits the Galápagos. It is similar in appearance to the sei whale, but it is noticeably bigger. The blue whale’s skin is blue-grey and somewhat mottled with paler spots, giving this whale a shiny or silvery appearance when seen from a distance.
When a blue whale surfaces and blows, it has a very tall spout of at least thirty feet coming from a double blowhole. It has a long, rolling back that appears after the head has submerged, followed by a small, stubby dorsal fin set well to the rear, near the tail. Like all baleen whales, blues are seasonal feeders; and it eats mostly in summer. It will lunge into a school of prey — mostly copepods (small crustaceans) — swelling its throat to four times the normal width. It closes its mouth, expels the water, and swallows the thousands of food items retained by the baleen.
Blue whales travel at speeds of up to twenty-nine miles per hour, which helped them to survive until the arrival of steam-powered whale catchers in the 1800s. They weigh 100 to 175 tons.
How to identify the blue whale: The blue whale can be recognized by its huge size; very tall spout; long, gently arching, mottled blue-gray back; and small, set-to-the-back dorsal fin. It has a large tail — up to twenty-five feet wide.
Bryde’s Whale (Balaenoptera edeni)
Of all the baleen whales, the Bryde’s whale is the one you are most likely to see in the Galápagos. It is smaller than the sei whale. The head of the Bryde’s whale has three distinctive ridges. It dives deep and often shows its head on surfacing, followed by an arched roll of its blue-gray back. It can weigh up to forty-four tons. Bryde’s whales are rapid swimmers, changing speed and direction frequently.
How to identify the Bryde’s whale: The Bryde’s whale rarely shows its flukes when it dives. The crescent-shaped dorsal fin is up to a foot-and-a-half long, and it has a point. This whale has a narrow spout that may be thirteen feet high.
Humpback Whale (Megaptera novaeangliae)
The humpback whale is one of the more easily identified whales in the Galápagos. It has a broad, round head and a string of fleshy tubercles or knobs that form a median ridge. The edges of its jaws also have rows of knobs. Its body is dark-blue or black, and it has white throat grooves.
The humpback is heavily built and narrows rapidly to the tail. It has the longest flippers of any animal, and the leading edges are heavily scalloped. The spout is a broad balloon up to ten feet high.
The humpback’s dorsal fin is short and squared and appears only as the body humps up to dive. The tail flukes, which are white underneath, are also scalloped on the trailing edge and are often raised high when diving. The humpback frequently breaches, leaping clear of the water.
Humpbacks like to “spy-hop,” raising their heads vertically out of the water and twisting around to get a good look. They weigh thirty-five to forty-five tons.
How to identify the humpback whale: The humpback whale has a knobby head, humped back, and long flippers. It has a fatty pad at the base of the dorsal fin, which varies in shape from almost flat to tall and triangular. It shows its flukes when diving, and its spout is broad and rises to a height of ten feet.
Minke Whale (Balaenoptera acutorostrata)
The minke is the smallest of the baleen whales. It has a laterally flat and pointed head and distinct white patches on its flippers. Its dorsal fin is slightly hooked and appears at the same time as its indistinct spout, which is only six-and-a-half-feet high. Its back is strongly arched when blowing, and the flukes are never seen except when it breaches. It weighs eight to ten tons.
How to identify the minke whale: The dolphin-shaped minke whale is small with a pointed head and sharp snout. The dorsal fin appears at the same time as a minimal spout from its double blowhole. There are white patches on the flippers, and it strongly arches its back when diving. The fin and flukes only show when the whale is breaching.
Sei Whale (Balaenoptera borealis)
The slender sei whale has a dark, steel-grey back with a pale chest and pleated throat. The sei feeds close to the surface and when it blows, it does not arch its back or show its flukes. It gently appears and disappears. It has a single, distinct ridge on its head. It weighs about forty-nine tons.
How to identify the sei whale: Look for a slow, gentle blow. There will be no roll and no flukes shown. The spout is an inverted cone that is nine to ten feet high. The sei has a single ridge on its head and a slightly downward-curved jawline. Its dorsal fin is distinctively tall and pointed.
Bottlenose Dolphin (Tursiops truncates)
While not indigenous, bottlenose dolphins are often observed in the Galápagos. They are likely to appear in groups while the boat is underway and are known to ride the bow waves of ships and yachts, putting on “shows.” Their distance from the boat will vary; some will leap alongside and others will perform flips in the distance. They sometimes school with common dolphins and short-finned pilot whales.
Bottlenose dolphins are dark gray or black on the back and paler underneath. Their name stems from their short beaks. The dorsal fin is six to eight inches high and shaped like a sickle, curving backwards.
When seen at night, the dolphins may seem to glow as they stir up thousands of tiny, phosphorescent creatures causing bioluminescence. If they are close to the boat, you may hear their high-pitched squeaking.
They weigh about 1,100 pounds.
How to identify the bottlenose dolphin: Look for the short beak, a back-curved dorsal fin, and a boundless sense of playfulness.
Common Dolphin (Delphinus delphis)
The common dolphin is smaller and sleeker than the bottlenose dolphin. It has a dark-gray back and undertail. While the underside is mostly white, there is an elaborate pattern of pale gray and buff markings on the flanks, which can vary by individual but generally have an hourglass shape. A dark stripe runs forward from the flipper to the chin.
The common dolphin has a large dorsal fin that is more upright than that of a bottlenose dolphin and more pointed than that of the striped dolphin. It has a longer beak than the bottlenose dolphin.
These dolphins travel in large groups — often several hundred strong. They may weigh as much as 297 pounds.
How to identify the common dolphin: Look for a long beak, buff-and-gray flank markings, an upright dorsal fin, and lots of speed and maneuverability.
Orca (or Killer Whale) (Orcinus orca)
The most frequently viewed, toothed whale in the Galápagos is the orca, sometimes called the “killer whale.” An orca is a versatile predator and will eat dolphins, fur seals, penguins, sea lions, and other large animals.
The orca has a blunt, round head and is clearly identifiable by its jet-black-and-white coloration. The back, apart from a gray “saddle” behind the dorsal fin, is black; while the throat, belly, and flank behind the dorsal fin are white. Its flippers are large and paddle-shaped.
There is a conspicuous white patch around and behind the eyes. In the adult male, the dorsal fin can be six feet tall and may appear to lean forward. It is larger than in any other whale. In the female, it is a bit smaller and curved backward.
Orcas generally travel in family groups called “pods.” They like to spy-hop and porpoise. They weigh eight to eleven tons.
How to identify the orca: Look for the black-and-white coloration; powerful, stocky body; and a large dorsal fin.
Short-Finned Pilot Whale (Globicephala macrorhynchus)
The short-finned pilot whale is the only pilot whale found in the Galápagos. You may see groups of up to thirty or forty individuals cruising on the surface of the sea. The short-finned pilot whale is shorter and much slimmer than the orca. It is almost all black, apart from a gray, anchor-shaped blaze on the belly and white streaks behind the dorsal fin and each eye. It has a round, melon-shaped head and a round, long, back-curving dorsal fin. Short-finned pilot whales weigh from one to three tons.
How to identify the short-finned pilot whale: Look for a bulbous forehead; a large, rounded, back-curving dorsal fin; and large numbers of them cruising on the surface.
Sperm Whale (Physeter macrocephalus)
During the 1800s as the Industrial Revolution demanded more and more oil, the sperm whale was hunted to the brink of extinction for its blubber. When humans began extracting oil from the earth, however, the sperm whales were spared.
The sperm whale has an unmistakable profile with an enormous, square-ended head, which emerges first from the water. Its body is colored a dark steel-gray, and its skin is corrugated. Its head is often covered with large, circular scars, a result of encounters with the giant squid, the whales’ main food source. The sperm whale is the world’s largest carnivore.
The dorsal fin on this whale is almost nonexistent and is more of a low, rounded hump, followed by four or five smaller lumps. The flippers are very small, but the tail is large and always thrown clear of the water as the whale dives. Its spout is nine to sixteen feet in height and is directed forward at an angle of 45 degrees and to the left because the blowhole is located on the front of the head, offset from the median line. It weighs fifteen to forty-five tons.
How to identify the sperm whale: Due to its extremely deep dives, it is rare that visitors encounter a sperm whale close-up, but it is not uncommon to see its spout on the horizon or its giant tail rise out of the water in the distance as the whale dives. Look for a large, square head; an angled spout; and a minimal dorsal fin.
Striped Dolphin (Stenella coeruleoalba)
In size, the striped dolphin falls between the larger bottlenose dolphin and the smaller common dolphin. But it is less frequently seen than the other two and rarely bow rides.
A distinct and striking color pattern with a complex of bold and thin stripes, one which extends from the eye to the flipper and another set of stripes that run down the sides of the body to the rear flanks, distinguishes them from other cetaceans and is the origin of their common name. Their beaks, tapered flippers, tails, and backs are colored a dark blue-gray. Their undersides are mostly white.
The beak of the striped dolphin is shorter than that in the bottlenose and common dolphins. The striped dolphin weighs between 330 to 350 pounds.
How to identify the striped dolphin: You can distinguish a striped dolphin from a common dolphin by its more rounded dorsal fin. The dark line running forward from the flipper goes to the eye and not the chin, as it does in the common dolphin. Unlike the bottlenose, the striped dolphin almost never bow rides.
Where to see cetaceans: Sperm and Bryde’s whales, the orca, and common and bottlenose dolphins are present year-round. The blue whale and humpback whale are seasonal. Cetaceans tend to be more in the western waters, especially between Isabela and Fernandina, due to the upwelling of the Cromwell Current.
Fish: Cartilaginous and Bony
Because water temperatures in the Galápagos can fluctuate from 68 degrees Fahrenheit to 76 degrees Fahrenheit, depending on the time of year and the location, the islands have a mix of temperate and tropical types of fish. The fish are divided into two main groups: cartilaginous — which includes sharks and rays — and bony.
Close to thirty shark species are found in Galápagos waters. They range from the giant (up to forty feet) but harmless whale shark to the small (5.5-foot) Port Jackson shark. Some common species are the hammerhead shark, the horn shark, the tiger shark, and the whitetip and blacktip reef sharks.
In sheltered bays, you may find small rays such as the spotted eagle ray and the golden ray. In open water are larger eagle rays and manta rays. You’re most likely to catch sight of a manta ray as it leaps out of the water and falls back with a loud slap, due to its maximum spread of twenty-five feet.
Stingrays are common at some beaches. Because they favor hanging around the sandy bottoms of the shallows and can inflict an extremely painful wound to waders and paddlers, it’s a good idea to enter the water by shuffling your feet. This gives stingrays the chance to swim away before you step on them.
More than four hundred species of fish from 112 families have been recorded in the Galápagos. About forty-one species are endemic, while about 60 percent have their origins in the tropical eastern Pacific. Since some of these fish can change color in a few seconds depending upon their mood — and some change shape and color with age and sex — identification is often difficult. Commercially caught fish include grouper (called bacalao), bonitos, herring, tuna, and anchovies.
Snorkeling in the Galápagos is the best way to see schools of thousands of tropical fish. Your naturalist guides can help you identify the more common species, which include blue parrotfish, blue-eyed damselfish, concentric puffer fish, hieroglyphic hawkfish, large-banded blenny, white-banded angelfish, yellow-bellied triggerfish, and yellow-tailed surgeonfish. Less frequently, you may spot the dramatic Moorish idol, a white-and-yellow fish with vertical dark bands and a long, white streamer trailing out from its dorsal fin.
Where to see them: Near the beaches or while snorkeling.
Insects and Spiders
Two-thirds of the invertebrates (animals lacking a backbone) found in the Galápagos Islands are insects — more than seventeen hundred species. However, only a very small percentage of these are likely to be seen by visitors. The arid, almost desert-like climate of much of the archipelago provides an inhospitable environment for most insect species. Many are present in numbers only after heavy rains or at nighttime.
Probably some of the most easily seen and most attractive insects are the butterflies. There are ten species or subspecies resident in the islands, three of which are thought to be endemic. There are several species of ants, beetles, centipedes, cockroaches, crickets, dragonflies, flies, grasshoppers, moths, and spiders. There are only a few wasps and one species of bee and praying mantis, each. There are two scorpions in the Galápagos. The scorpions are rarely encountered; and though their sting can be painful, they are not normally dangerous.
Where to see them: In dark, humid places; after heavy rains; or at night.
The first invertebrate that you’re most likely to encounter on your Galápagos adventure is the Sally Lightfoot crab. This small resident is bright red on top and blue underneath. Found on almost every rocky beach, these beautiful, colorful crabs offer a striking contrast on black lava.
Juvenile Sally Lightfoots are almost all black with small orange spots, which helps to camouflage them against predators. The neon adults, however, stand out on the dark rocks and must rely heavily upon their alertness to escape from predators. If you approach them, they will quickly scurry away; they are even capable of running across the surface of the water in tide pools.
While Sally Lightfoots are very alert to moving objects, they will approach you if you sit very still, a strategy employed by herons. Often, you will see a lava heron standing motionless on a rocky beach. When a crab comes within reach, the bird will lunge forward and, if successful, will shake and bang the crab against rocks until its legs fall off before devouring it.
Another crab species you may run into in the Galápagos is the pale-colored ghost crab. You are actually more likely to see their burrows, tracks and “sand balls” (pellets of sand that they have sorted through for microorganisms) than the crabs themselves. Named for their elusive nature, speed, and mostly nocturnal activity, you might catch one peering out of its burrow at you, its eyes extended vertically at the end of movable stalks.
In tide pools, look for the hermit crab, which lives in an abandoned snail shell that it carries around on its back. Lacking the hard, external skeleton typically associated with crustaceans, these “hermits” live in discarded houses. As a young hermit crab grows, it finds successively larger shells to fit into.
At low tide, many marine invertebrates and cephalopods — such as barnacles, chitons, marine snails, octopuses, sea anemones, and starfish — wait to be discovered in the pools. As you go further into the water with a mask and snorkel, you may find many more species, including sea cucumbers; sea stars; and crowned, green, pencil-spined, and white sea urchins.
Where to see them: You’ll find such species on the beach, in the intertidal zone, and while snorkeling.
Marine Mammals: Galápagos Fur Seal and Galápagos Sea Lion
Because the long journey to the Galápagos was difficult for mammals, there are only six species that are indigenous to the islands. Of those, two are rice rats and two are types of bats. The other two are the Galápagos fur seal and the Galápagos sea lion.
Millions of years ago, the ancestors of the Galápagos fur seal and the Galápagos sea lion were land creatures who hunted the coastlines for food. While they adapted to life in the water, unlike other marine mammals such as whales and dolphins, they did not become completely independent of the land. Graceful under the waves, they still possess extreme maneuverability in pounding surf and along jagged rocks.
Galápagos Fur Seal (Arctocephalus galapagoensis)
Despite its confusing name, the endemic Galápagos fur seal is not a true seal. Technically, it’s a fur sea lion. Both fur seals and sea lions have small but visible ears and use their front flippers for swimming. The fur seal differs from the sea lion in that it is smaller (77 to 165 pounds); it has large, prominent eyes; its ears stick out more; the front flippers are relatively larger for climbing; and it has a shorter snout, giving the head a bear-like appearance. Its Latin name, in fact, means “bear head” (Arcto = bear; cephalus = head).
Because Galápagos fur seals are so secretive, researchers can only guess at their numbers. Twenty-five thousand are thought to inhabit the rocky shores of the archipelago. They prefer places where there is deep water immediately offshore. Sea lions, on the other hand, frequent sandy beaches and shallower water. And a fur seal’s thick coat — an outer layer of long hairs and an inner layer of short, dense fur — makes it love the shade more than the sun, in opposition to the sea lion.
Galápagos fur seals feed on fish and squid, diving to depths of up to 330 feet. The animals like to hide out in cool caves and grottos formed on steep shores during the heat of the day, and they hunt mainly at night to avoid shark attacks.
The breeding season is from August to November. A cow will mate immediately after giving birth, but fertilization of the egg doesn’t take place for another few months due to delayed implantation. At best, one pup manages to survive every two years, owing in part to competition with older siblings. In contrast, sea lions typically are able to raise a pup a year.
Fur seals were almost hunted to extinction during the nineteenth century because of their dense and luxuriant fur. They have made a remarkable comeback.
Where to see them: Because of their secretive habits, Galápagos fur seals are seen less frequently than Galápagos sea lions. They will always be on rocky coasts; never on sandy beaches. Found on Fernandina, Genovesa, Isabela, Santiago, and Seymour Islands.
Galápagos Sea Lion (Zalophus wollebacki)
The largest animal found on land in the Galápagos is the endemic sea lion. Bulls grow to be up to seven feet in length and eight hundred pounds. There are currently about fifty thousand of them in the Galápagos.
The territorial bulls, which have a discernable bump on their heads — distinguishing them from females — are aggressive and have been known to chase swimmers out of the water. They have well-defined territories that they guard jealously, especially during the mating season. Territory tenure lasts anywhere from a few days to as much as three months, when the bull will be ousted by a fresher, better-rested male. The females and young, on the other hand, are extremely playful and will often swim around you if you snorkel.
The mating season may vary from island to island, but it is generally from June to September. A dominant bull’s harem consists of several cows, immature sea lions, and pups.
Mating normally takes place in the water and within four weeks of the cow giving birth. Because of delayed implantation, however, the egg is not implanted in the womb for another two months. Gestation takes about nine months. The mother will nurse her single pup for almost a week before returning to the water to feed. The pup grows rapidly on the mother’s very rich milk. A cow and her pup recognize each other by smell and bark.
The pups start fishing for themselves at about five months. In the meantime, they stay with other pups in a “nursery,” but they are allowed to swim and play in shallow water — often with Galápagos visitors.
Sea lions can dive up to five hundred feet, and the majority of their diet consists of sardines. They can live up to twenty years of age. Unfortunately, sea lions are especially vulnerable to human activity. Their inquisitive and social nature makes them more likely to approach areas inhabited by humans and thus to come in contact with human waste, fishing nets, and fishing hooks.
Where to see them: Galápagos sea lions may be found at sea, anywhere around the islands, and on sandy beaches. Snorkeling and kayaking with the playful pups is often the highlight of a visit to the Galápagos.
One of the most astonishing aspects to the wildlife of the Galápagos Islands is that the land animals are predominantly reptiles; whereas in most of the world, mammals are dominant. In 1845, Charles Darwin wrote that the Galápagos seemed like a “paradise” for reptiles. He was right: The islands are dry and hot for much of the year, conditions reptiles favor.
Cold-blooded and with a slow metabolism, reptiles do not need a lot of food. Their scaly skin is an effective protection against the sun, and rock crevices provide the right amount of shade when it gets too hot. And since native mammals on the archipelago are few, they face minimal competition and predators.
A benefit for travelers is that these iconic reptiles are easily approached.
Galápagos Giant Tortoise (Geochelone spp.) and Lonesome George
It’s often said that of all the Galápagos Islands’ wildlife, it is the giant tortoise that most symbolizes the place. Part of that is due to their complicated history with us.
In fact, the word galápago is an Old Spanish word for saddle, referring to the shape of some of the giant tortoises’ shells. While there is only one species of giant tortoise, fourteen (or possibly fifteen) subspecies evolved — each in some way adapted to the vegetation of the island of its residence. On Isabela, five subspecies evolved: one for each major volcanic region.
Specific adaptations can be seen in the shape of the shell. The saddle shape — with an elevated, arched front end, which is found on tortoises from Española, Fernandina, Pinta, and Pinzón — allowed the animals to stretch out their long necks in order to reach for tall vegetation on these drier islands. On the other hand, a dome shape — with a shorter profile and blunt front end for pushing through dense brush; found on tortoises on Isabela and Santa Cruz — most often occurs on islands with lush highlands. Because they live on drier islands with less food, saddleback tortoises tend to be smaller than those with dome-shaped shells.
Of the varieties of Galápagos giant tortoise, three are extinct: those that once lived on Fernandina, Floreana, and Santa Fé. Today, many experts believe that the fourteen or fifteen races are actually distinct species.
Giant tortoises, which may weigh up to 550 pounds, are vegetarians, and they can fast for long periods of time. These facts made it possible for the tortoises to make the long voyage to the Galápagos on rafts of tangled vegetation; and once on land, to survive the arid conditions on many of the islands. They eat grass, leaves, lower parts of bushes, and the cactus pads of the prickly pear. During the wet season, they wade in mud ponds. At night, they hide under shrubs. Their first reaction when threatened is to retract head and legs inside their shells, accompanied by their emitting a conspicuous hiss of escaping air. A turtle that gets rolled upside down finds it difficult to get back on its legs and then becomes vulnerable.
Unfortunately, buccaneers and whalers took advantage of the tortoise’s attributes. Over the course of the years of their visits, they managed to carry off two hundred thousand of the reptiles, knowing they would survive in their ships’ holds without food or water for up to a year and thus provide a ready source of fresh meat. The tortoises were also killed for the oil that can be made by rendering down their fat reserves. Today, it is thought that only fifteen thousand individuals exist. Rate of growth for these giants is determined by the availability of food, with wetter years producing faster growth. The scutes of the carapace have annual growth bands, but they are not a good indicator of age since the outer layers are rubbed off in the normal wear and tear of living.
Most giant tortoises reach sexual maturity at about twenty to twenty-five years of age. Mating typically takes place in March and April. Males will mock fight and shove other males in contests of dominance, and then try to seek out a suitable female. During copulation, the males make loud snoring or grunting noises, often described by those who live and work in the islands as the loudest noise in the bush.
Having mated, the female will look for a dry area with a reasonable amount of sand or depth of earth where she can make a nest. Egg laying lasts from June to December. The female will dig a shallow pit of about one foot deep with her hind legs, a process that may take five to twelve hours. About two to sixteen, tennis-ball-sized eggs are laid and then covered up. She then urinates on the nest and tamps it down with her plastron (the underside of her shell) as additional protection. The eggs take four to five months to develop.
After struggling to the surface, the hatchlings quickly locate cover to hide themselves from predators, such as hawks and feral cats and dogs. Most of the young die within the first ten years of life. Once it reaches adulthood, however, a giant tortoise may have a lifespan of about 150 years.
Today, an on-going, tortoise-breeding project at the Charles Darwin Research Station on Santa Cruz rears giant tortoises from collected eggs and reintroduces them to their native islands when their shells become strong enough to withstand the threat of natural and introduced predators. Of the eleven species that were once endangered, ten have been brought up to guarded levels. The most noted success story is on Española. When the project began, that island’s population of giant tortoises consisted of two males and eleven females. Amazingly, a third male was discovered at the San Diego Zoo. All were brought to the Charles Darwin Research Station. Today, these thirteen tortoises are the parents of more than a thousand young — now roaming free on Española.
|Giant Tortoise Species
|G. hoodensis (1,000)
1) G. vandenburgi (Alcedo Volcano) (largest population; about 5,000)
2) G. vicina (Cerro Azul Volcano) (1,100–1,200)
3) G. microphyes (Darwin Volcano) (about 1,000)
4) G. guntheri (Sierra Negra Volcano) (about 700)
5) G. becki (Wolf Volcano) (thought to be 1,200–1,500)
G. abingdoni (only one remaining*:
*when this guide was written
|G. ephippium (500)
|G. chatamensis (original population extinct; second population about 1,800)
|G. nigrita (second largest population; about 3,000)
|G. darwini (about 1,200)
Where to see them: The best place to view the giant tortoises is at the Charles Darwin Research Station on Santa Cruz Island and at the Tortoise Reserve in the Santa Cruz Highlands. In the wild, only the San Cristóbal, Santa Cruz, and Alcedo Volcano tortoises are likely to be seen.
Pinta was once a popular stop for pirates and whalers in the 1800s. Located in the north of the archipelago, the island was also a good home to thousands of tortoises.
Because the giant tortoises could remain alive in a ship’s hold for up to a year with little food or other necessities, seafaring folk saw the tortoises as a valuable source of fresh meat. The sailors would carry off as many of the reptiles as their ships could hold. First, they collected the female tortoises since their smaller size made them easier to handle and store. And because the females would go to the beach to lay eggs, the raiders didn’t have to search very far to find them. When the female population began to become scarce, the males were gathered up. The tortoise population on Pinta visibly diminished.
By the time researchers from the California Academy of Sciences visited Pinta in 1906, they discovered the tortoise population had dwindled to a mere three male tortoises. The scientists collected them, believing that this was the end to native tortoises on Pinta.
In the 1950s, fishermen working the nearby waters also decided that Pinta would make a good stop to restock meat supplies while at sea. Since tortoises were no longer available, they released goats, which quickly multiplied and devoured the little vegetation that existed.
In 1971, the National Park Service began an eradication program to get rid of the feral goats on Pinta. To the surprise of everyone, one remaining Pinta tortoise was found still on the island. The last of his subspecies, he was named “Lonesome George.”
The park service relocated George to the Charles Darwin Research Station (CDRS) on Santa Cruz Island. Efforts were made to encourage George to breed with female giant tortoises from Wolf Volcano on Isabela Island, found to be the closest morphologically to the Pinta tortoises. Researchers even offered a $10,000 reward if someone could come up with a suitable mate for George. On July 21, 2008, it seemed there was good news. Tortoise eggs were discovered in the pen that George shared with his companions. The eggs were placed in incubators at the Captive Breeding Center at the CDRS. After 130 days, however, tests confirmed that the eggs were never fertilized.
George remains the last of his kind, the quintessential symbol of the crisis of extinction.
Where to see him: After this guide was written, Lonesome George was found dead on the morning of June 24, 2012 by his caretaker of 40 years. He was believed to have been over 100 years old, though this is not incredibly old for Galápagos tortoises. Lonesome George will be embalmed and returned to Santa Cruz Island, likely to the Charles Darwin Research Station at Puerto Ayora where he lived his final decades.
Land Iguana (Conolophus subcristatus and Conolophus pallidus)
There are two species of land iguanas in the Galápagos: Conolophus subcristatus, which is widespread; and Conolophus pallidus, found only on Santa Fé Island.
Both species, however, are similar in appearance. They are pale to dark yellow in color, measure three feet or more in length, and may weigh up to twenty-eight pounds. The Santa Fé land iguana tends to be whitish — sometimes with dark, chocolate-brown patches — and its spine is more pronounced, extending farther down its back. Skin scales on the Galápagos land iguanas make them look like little knights in chain mail.
About five thousand to ten thousand land iguanas live in the Galápagos. Today, Conolophus subcristatus may be found on the islands of Fernandina, Isabela, Santa Cruz, Seymour, and South Plaza. They formerly existed on most of the other islands in the archipelago as well, but human hunting and competition with introduced animals, such as dogs, goats, pigs, and rats, caused their demise.
The food of choice for the land iguana is the prickly pear cactus. Sometimes, they can be seen standing on their rear legs, trying to reach the succulent pads and yellow flowers. Their mouths are leathery, enabling them to eat the cactus pads whole without removing the spines. Because land iguanas live in the dry lowlands, they see virtually no fresh water during the year. The cactus provides them with both food and water. Land iguanas also eat other plants; and juveniles, especially, enjoy insects.
Organizing themselves into small colonies, land iguanas are burrowers. Their shallow tunnels provide shelter at night, shade during the day, a nesting place, and a temporary home for hatchlings.
A symbiotic relationship exists between various species of birds on the different islands and land iguanas. The birds eat ticks and other parasites off the reptiles, cleaning them and obtaining a meal. To signal that it is receptive to a nearby bird’s attentions, the iguana will stand on all fours, allowing the bird free access as it hunts for pests.
Between six to ten years of age, land iguanas reach sexual maturity. Males are highly aggressive to one another and often engage in head-bashing, blood-drawing battles. Mating takes place at the end of the year, with egg laying occurring from January to March (mating takes place in June on Fernandina ). Females will defend their nests of seven to twenty-three eggs until those eggs hatch at three to four months.
Predators of land iguana eggs are beetles; while hawks, herons, owls, and snakes prey on hatchlings. The expected survival rate of a young land iguana in the wild is less than 10 percent. However, once a land iguana makes it to adulthood, it may live more than sixty years.
Marine Iguana (Amblyrhynchus cristatus)"
The world’s only sea-going lizard is found on the rocky shores of most of the Galápagos Islands. There are seven subspecies of the marine iguana, which vary in size and color from island to island:
- Amblyrhynchus cristatus albemarlensis (Isabela Island)
- Amblyrhynchus cristatus cristatus (Fernandina Island)
- Amblyrhynchus cristatus hassi (Santa Cruz Island)
- Amblyrhynchus cristatus mertensi (San Cristóbal and Santiago Islands)
- Amblyrhynchus cristatus nanus (Genovesa Island)
- Amblyrhynchus cristatus sielmanni (Pinta Island)
- Amblyrhynchus cristatus venustissimus (Española Island)
In general, however, the marine iguana has a blackish skin, which changes to a red or red-green tinge in the males during mating season. Their dark coloring blends in with the lava rocks. They have a pronounced spiny, crest that is most prominent on their heads but runs all the way down their backs and tails. Their tails account for half the size of their three- to four-foot-long bodies. Their scaly skins and their habit of occasionally snorting out little clouds of brine (or salt) spray into the air through a special gland connected to their nostrils remind some visitors of dragons. This salt-sneezing gives the marine iguana a white-encrusted forehead.
Estimated to number between two hundred thousand and three hundred thousand individuals, these reptiles gather in herds and sometimes pack one on top of another to conserve heat. They may keep frozen in one position for hours at a time.
A marine iguana lives largely on land and spends much of its day sunbathing. A vegetarian, it feeds mainly on intertidal, red or green algae on the exposed lower portions of the rocks. A blunt nose comes in handy for gathering up the algae. Larger males, however, may go into the water to feed and have been recorded diving to depths of forty feet, staying submerged for up to an hour. A male may lose as much as 20 degrees Fahrenheit during its daily excursion into the water, and it takes much of the day to restore its body temperature to the normal 96-degree-Fahrenheit mark, as well as to replenish its oxygen supplies.
Breeding occurs at different times on different islands, but typically it starts in December or January. This is a good time to witness the males displaying aggressive, territorial behavior. The conflicts consist mostly of head butting, resulting in some scarred faces. Head-bobbing behavior occurs year-round.
Females lay their eggs usually in March or April. The female excavates a nest in the sand and deposits two to four, leathery, elongated eggs. During the first ten days of the three- to four-month incubation, the nest is fiercely guarded. Hatchlings, however, are not given much parental protection. While the adult marine iguanas’ only natural predator is the Galápagos hawk, feral cats and dogs prey on them. Young marine iguanas, as well as eggs and hatchlings, though, are vulnerable to frigatebirds, Galápagos hawks, herons, lava gulls, and snakes on land; and moray eels and other predators in the water.
If they manage to safely navigate their world, marine iguanas may live twenty-five to thirty years in the wild.
Where to see them: A complete population survey of the marine iguana would be difficult to accomplish because of the nature of the coastlines that these reptiles inhabit. However, estimates of the population approach hundreds of thousands. You will probably see marine iguanas on Española, Fernandina, Genovesa, Isabela, San Cristóbal, Santa Cruz, Santa Fé, Santiago, Seymour, and South Plaza Islands. The marine iguanas on Española are the most brightly colored.
Lava Lizards (Microlophus spp.)
Counted together, the several species of endemic and colorful lava lizards constitute the most abundant type of reptile in the Galápagos. While you may find them on most of the major islands, only two species occur on a couple of islands, while one species each lives on seven other islands.
Ranging in color from black with gold stripes to grayish-yellow to speckled copper, the lizards have adapted to blend in with their environments. Lava lizards that reside primarily on lava are dark in color, while those living on a sandy beach will sport lighter hues. These creatures also have the ability to change colors if they are threatened or if there is a change in temperature.
Like other reptiles, lava lizards rely on the sun for their own internal heat. They like to begin their days basking on warm rocks before going out to hunt for ants, beetles, flies, grasshoppers, moths, and spiders and partaking of some plants. Although they are classified as omnivores, lava lizards play a particularly significant role in controlling insect populations on the islands.
At mid-day, when the sun, rocks, and sand are at their hottest, lava lizards seek shade. In late afternoon, they become active again. Toward dusk, they bury themselves under leaves or loose soil in lava cracks to stay warm for the night. And as with other reptiles, lava lizards can regenerate a tail that is exchanged for freedom.
Males make take up to three females in their harems. The lizards are extremely territorial and can be seen on top of rocks doing “push-ups,” where they’ll stand high on all fours — usually sideways to their opponent to maximize their size and show off their spiny crests — extend the scales on their backs, and bob up and down. Each island’s lava lizard population has its own precise pattern of push-up. This behavior, which becomes more prevalent between July and November during the mating season, is meant to assert dominance and indicate ownership.
Researchers believe lava lizards have color vision, which plays a role in their courtship. Females show bright red throats during the mating season. They lay three to six eggs every three to four weeks deep in the soil. Incubation lasts about three months. Hatchlings are about one-and-a-half inches long.
Lava lizards live up to ten years, which is a relatively long time for such a small animal. They are generally five to six inches in length, but they may grow up to a foot long.
Where to see them: On most of the major islands in the lowlands, except for Genovesa, Darwin, and Wolf:
- Galápagos Lava Lizard (Microlophus albemarlensis); found on several islands, including Baltra, Fernandina, Isabela, Rábida, Santa Cruz, Santa Fé, Santiago, and Seymour
- Española Lava Lizard (Microlophus delanonis)
- Floreana Lava Lizard (Microlophus grayii)
- Marchena Lava Lizard (Microlophus habeli)
- Pinta Lava Lizard (Microlophus pacificus)
- Pinzón Lava Lizard (Microlophus duncanensis)
- San Cristóbal Lava Lizard (Microlophus bivittatus)
- Santa Cruz Lava Lizard (Microlophus indefatigabilis); found on Santa Cruz and Santa Fé
- Santiago Lava Lizard (Microlophus jacobi)
Turtles: Galápagos Green, Hawksbill, Leatherback, and Olive Ridley
Galápagos Green Turtle (Chelonia mydas agassisi)
A subspecies of the Pacific green turtle, the Galápagos green turtle is by far the commonest species of marine turtle found in the Galápagos. It is the only turtle that breeds in the islands.
There is much that is still a mystery about this reptile. It can hold its breath for hours at a time, a phenomenon that is still not well understood. And how and why females return to the very beach on which they were hatched to nest and lay their own eggs is still up for debate.
The Galápagos green turtle is a vegetarian, feeding on algae — similar to the marine iguana. However, the green turtle’s diet is not as narrowly restricted; it will eat grasses that grow in shallow waters. Juveniles may eat plants, jellyfish, crabs, sponges, snails, and worms. The shell of a Galápagos green turtle may be almost three feet long and is covered by scales that are generally dark green to black, although they vary and can be as light as yellow. However, Galápagos green turtles cannot pull their heads and limbs inside of their shells, which makes them more vulnerable to predators. They are called “green” because of the color of their flesh. Their paddle-like limbs are an aid in making them proficient swimmers.
The turtles spend most of their lives in shallow lagoons and waters around the islands, though sometimes they are spotted in the open sea between the islands. They are one of the largest turtle species, weighing between 110 to 450 pounds, and they measure two-and-a-half to five feet in length. Males are smaller than the females and have a concave plastron. They have claws on the bend of the front flippers to grasp the carapace of the female during mating, and they have a longer tail. Females have a convex plastron.
The end of the year starts the mating season for Galápagos green turtles. They reach sexual maturity at twenty to twenty-five years of age and are quite promiscuous, especially in November and December, when mating activity in the water can often be observed. Usually a mating couple bobs, while another male waits his turn nearby.
Unlike males that live their entire lives at sea, females come ashore to nest and lay eggs. Mainly from December to June — with a peak in February — females land on sandy beaches at night to nest. Each female’s egg-laying frequency is every two to three years. In any one season, a female may come ashore up to eight times at about two-week intervals, laying seventy to eighty eggs at a time. She will excavate a large pit in the sand — with a smaller egg chamber at the bottom — above the high tide mark and deposit her eggs, a process that takes about three hours. She then covers the eggs with sand to protect them from the sun, heat, and predators and returns to the ocean.
The newly laid eggs incubate in the sand for about sixty days. The temperature inside the nest determines the sex of the hatchlings, with cooler nests (under 86 degrees Fahrenheit) producing a clutch of males and warmer nests (more than 86 degrees Fahrenheit) producing females. The only natural predators of eggs in the nest are a beetle (Trox suberosus) and the ghost crab.
On a clear, moonlit night, the hatchlings will dig themselves out of their nests and scramble towards the water. With only a soft shell about two inches long, these young are extremely vulnerable on their treacherous journey to the open sea to predation by seabirds, Galápagos hawks, and mockingbirds. And once in the water, sharks and orcas lurk. If they are successful in making the trip, however, the turtles will swim away for years. Not much is known about this period of their lives.
Despite the high mortality rate of the hatchlings by natural and introduced predators, such as feral pigs and rats, the number of marine turtles continues to remain high in the Galápagos.
Where to see them: Galápagos green turtles are usually spotted late in the year on quiet beaches and in secluded lagoons. A favorite Galápagos green turtle location is Black Turtle Cove on the northern end of Santa Cruz Island and the lagoon at Elizabeth Bay on Isabela Island.
Hawksbill Turtle (Eretmochelys imbricata)
Unlike the Galápagos green turtle, the hawksbill turtle is omnivorous, feasting largely on crabs, jellyfish, seaweed, shellfish, and sponges. However, in appearance the two are quite similar, and it may be hard to tell them apart.
The hawksbill is smaller than the Galápagos green turtle; and it has a much more amber-brown-colored carapace, which is the source of the color term tortoiseshell. The plastron or underside of the hawksbill turtle is yellow. Its head is elongated and tapers to a point, with a beak-like mouth that gives the species its name. The shape of the mouth allows the hawksbill turtle to reach into holes and crevices of coral reefs to find sponges — its primary food as an adult — and other invertebrates. Hawksbill turtles are unique among sea turtles in that they have two pairs of prefrontal scales on the tops of their heads, and each of the flippers usually has two claws.
As with the Galápagos green turtle females, female hawksbills will return to their natal beaches every two to three years to nest at night, approximately every fourteen to sixteen days during the nesting season. A female hawksbill generally lays eggs in three to five nests per season, which contain an average of 130 eggs each.
Where to see them: Hawksbill turtles usually nest high up on both calm and turbulent pocket beaches, with little or no sand.
Leatherback Turtle (Dermochelys coriacea)
Leatherback turtles are the largest turtles in the world. An average adult is 6.5 feet long and weighs up to two thousand pounds. It may have a flipper span of up to ten feet.
In contrast to other marine turtles, the leatherback is the only one that lacks a hard, bony shell. A leatherback’s carapace is approximately 1.5 inches thick and consists of leathery, oil-saturated connective tissue overlaying loosely interlocking dermal bones. The carapace has seven, lengthwise ridges and tapers to a blunt point. Its front flippers lack claws and scales, and they are proportionally longer than in other sea turtles. These large flippers make the leatherback uniquely equipped for long-distance foraging migrations. Its size and distinctive carapace make it relatively easy to identify.
In coloration, the leatherback is dark brown with white or yellow spotting, especially on the sides and flippers. Because leatherbacks lack the crushing chewing plates characteristic of sea turtles that feed on hard-bodied prey, they use their pointed, tooth-like cusps and sharp-edged jaws to indulge in a diet of soft-bodied pelagic prey, such as jellyfish. A leatherback’s mouth and throat also have backward-pointing spines that help retain such gelatinous foods.
Where to see them: Leatherbacks are the most migratory and wide-ranging of sea turtle species, however they will forage in coastal waters.
Olive Ridley Turtle (Lepidochelys olivacea)
The smallest turtle — about one hundred pounds — found in the Galápagos, the olive ridley grows to little more than two and a half feet in length and has a heart-shaped, olive-green carapace, from which it gets its name. There are often only five pairs of costal plates on the carapace, but that number may vary. Some individuals have been documented as having as many as nine pairs. Each of the four flippers has one or two visible claws.
The olive ridley is omnivorous, eating algae, crabs, fish, lobsters, mollusks, shrimp, and tunicates. It can dive to depths of about five hundred feet, to forage on benthic invertebrates.
Where to see them: The olive ridley is mainly a pelagic sea turtle, but it has been known to inhabit coastal areas, including bays and estuaries. Trans-Pacific ships have observed olive ridleys more than 2,400 miles from shore. Like all marine turtles, it is found throughout the tropics, but it is not known to breed in the Galápagos.
Challenges Facing Galápagos Wildlife
Introduced species are the most serious threat to the native animals of the Galápagos. Since the discovery of the Galápagos in 1535, humans have brought many alien species to the islands — plants and animals that otherwise would not have arrived in the archipelago. Black rats and house mice came as stowaways on ships. Beginning in the 1800s, settlers brought domestic animals — such as cats, cattle, dogs, donkeys, goats, horses, and pigs — that eventually escaped or were abandoned. Subsequently, feral populations formed and are sometimes today found on the islands.
The native animals did not have time to develop a defense against these new competitors and predators, and the impact has been devastating. On Santa Cruz, wild dogs attacked large colonies of land iguanas; on Santiago Island, wild pigs snatched the eggs of Galápagos green turtles; and on the island of Pinzón, rats killed every Galápagos giant tortoise hatchling, leaving only an ever-aging adult population of that subspecies. Goats wiped out huge stands of native plants, reducing the vegetation down to lifeless shrubs. This not only caused extinction of the plant species and soil erosion, but it also robbed the native wildlife of food.
While it’s known that introduced species cause devastation to native fauna and flora in the Galápagos, the threat from exotics in the marine environment is a more recent phenomenon and much study needs to be done. The continuing increase in trans-oceanic and regional vessels using the waters around the Galápagos, in inter-island traffic, in the number of cargo and other ships moving back and forth from the continent, and in the number of private vessels traveling through the islands greatly increases the threat of hull and anchor transport of potentially invasive marine species. Scientists aren’t yet sure how this will change the waters of the Galápagos.
The good news is that 95 percent of the archipelago’s native species remain intact today, due in large part to the islands’ remoteness and relatively recent discovery and settlement by humans. With care, we can stem the tide of further declines in the natural, native communities.
Efforts to Combat Invasive Animal Species
Ever since 1959, when the Ecuadorian government set aside 97 percent of the Galápagos Islands as a national park and the Charles Darwin Foundation was established, efforts have been conducted to control and eradicate introduced invasive species. Early efforts were aimed at eradicating the goat populations on the smaller islands. However, by the 1980s, the increase in tourism and the resident population made stopping any new introductions of equal importance with getting rid of the threats already there.
In 1999, the Galápagos Inspection and Quarantine System (or “SICGAL,” its acronym in Spanish) was created. The program, formally established in 2000 and implemented by the Ecuadorian Service for Agricultural Health, SICGAL works to prevent new species and organisms from being introduced into the Galápagos Islands by monitoring ports of entry and agricultural zones on the inhabited islands, utilizing protocols for fumigating incoming planes and boats, providing training for inspectors and technicians, and publishing and disseminating lists of permitted and prohibited products, among other efforts.
One of the most dramatic successes related to invasive fauna species came in March 2006, when Project Isabela was completed. Feral donkeys and goats were eradicated from northern Isabela; donkeys, goats, and pigs from Santiago; and goats from Pinta. Additional accomplishments included the eradication of fire ants on Marchena; cats on Baltra; and rock pigeons on Isabela, San Cristóbal, and Santa Cruz.
Currently, the Charles Darwin Research Station, the Galápagos National Park Service, and other organizations in the islands have set their sights on eliminating all feral burros, cattle, goats, and pigs from the archipelago; getting rid of introduced rodents from the islands; wiping out the freshwater tilapia in El Junco Lake on San Cristóbal; and instituting humane sterilization programs for cats and dogs on inhabited islands.
In addition, feasibility studies are being conducted on using biological controls to deal with introduced ants, wasps, and the mosquito that potentially carries the West Nile virus. Methods are being developed to control parasitic flies that endanger their host birds, and attempts to eradicate fire ants from the larger islands and priority small islands are still going on.
To protect the marine reserve, divers have been charged with making surveys of ship hulls to assess any dangers from epifauna associated with the Guayaquil port (the most important port in terms of maritime transport to the Galápagos).