Hammerhead sharks may grow very large, ranging anywhere from two to six meters in length in adulthood. They are social and spend time in groups of up to one hundred sharks, but they are also aggressive. They feed on other sharks, fish, rays, crustaceans and other marine life.
Every year the Hammerhead Shark mates, which is a violent process. The female is repeatedly bitten until she relents. Fertilization of the eggs is internal, unlike other shark species. The pups have a gestation period that lasts up to twelve months. The female has a litter of twelve to fifteen pups and once born, they are abandoned.
Birds
The Galápagos Penguin
The Galápagos Penguin is unique because it is the only penguin species to live on the equator. It is found north of the equatorial divide. This bird is endemic to the Galápagos Islands. It relies on the cool currents that exist due to the Humboldt and Cromwell currents. It is small and grows to just 35 centimeters tall.
The Galápagos Penguin is most commonly found on Fernandina Island and on Isabela. However, it may be observed on other islands as well, such as Floreana and Bartolomé. Snorkelers may be lucky enough to see a Galápagos Penguin diving underwater to catch fish. The penguin has black feathers on its outer part, and white underneath. It sports at black band over its breast and the eye to throat region has a white stripe.
This penguin may breed all year around, provided that the water temperatures are cool enough and that there are sufficient resources to rear young. It is thought that there are just 1000 pairs of penguins in the Galápagos. The couples are monogamous. After mating, the, eggs (one or two) are laid on the shore line. The egg is incubated for 40 days, with responsibility for this being shared by both male and female.
Blue-Footed Booby
The Blue-Footed Booby has distinctive large blue feet, and a mascot of the Galápagos Islands. Females are bigger than the males. The upper feathers are brown in color, with white lower parts. The wings are darker brown. The young remain brown for up to a year before getting their adult plumage. They are found in many parts of the islands, but some of the best viewing spots are at North Seymour, Española and San Cristóbal.
Those visitors who are lucky will get to see the famous Blue-Footed Booby mating dance. The male will lift his feet one by one with his beak pointed to the air. He will emit a loud whistle and open his wings. The male will prepare twigs for the female as an offering to win her over. Females will participate in the dance also by using the same display as the male, but instead of a whistle, she will honk.
Provided that there is sufficient food present, this booby species may mate at any time of the year. They will make a circle of dung within which the two or three eggs that are laid are placed. When there is not enough food, the older juveniles will push the younger out of the ring. This results in the mother no longer taking care of those outside of the ring.
Nazca Booby
The Nazca Booby was formerly known as the “Masked Booby.” It looks as though it has a black mask across its eyes. This looks this way due to some black skin that is found at the base of the bill of this bird. The bird is primarily white in color, with some black ends to its feathers and a black-colored tail. Of the three types of booby in the Galápagos Islands, the Nazca Booby is the biggest.
This kind of booby is commonly found on a few different islands. The best places to spot it are at Punta Suarez on Española Island, Genovesa, Daphne Major and at Punta Pitt on San Cristobal Island.
Like its booby cousins, the blue-footed and red-footed boobies, the Nazca Booby feeds only on fish. It also has a detailed and intricate courtship dance. The males and females are extremely similar in the way that they look. This means that the easiest way to tell them apart is to rely on sound. The females let out a quacking sound, while the males generally make a whistling noise.
Red Footed Booby
The Red Footed Booby has its name due to its bright red feet, which are very distinctive. These are the best means by which to identify this bird. The Red Footed Booby has outer feathers that are a brown color. It has a beak that is a blue-gray color and pink skin on its face. As boobies go, it is the smallest of the types of booby species that reside in the Galápagos Islands.
Red Footed Boobies differ to the other kinds because they nest up higher in tree tops. Other booby species nest on the ground. The next is created from sticks and guano and is a sort of platform. The Red Footed Booby has a courtship dance that is similar to that of the Blue Footed Booby, but the ritual is carried out up in the trees. Only one egg is laid and both parents take responsibility for its incubation. The incubation period is 45 days, and after the chick hatches, it needs support from its parents for an entire year.
Red Footed Boobies feed on fish, which they hunt for a long way from land. They find the fish that they need from submarine volcanoes. Red Footed Boobies are most commonly found at Genovesa and Punta Pitt at San Cristóbal.
Flightless Cormorant
The Flightless Cormorant is a bird that cannot fly because it has only stubs rather than proper wings. They are black on the top and have brown plumage underneath, with black feet and short legs. They are endemic to the Galápagos. To make up for the ability to fly, these Cormorants are superb swimmers. They feed entirely on sea animals, including octopus and eels.
Viewed on Fernandina (Punta Espinosa) and Isabela (the western visitor sites), the Flightless Cormorant has an intricate courtship. The mating dance is carried out in the water. This aquatic activity is followed by a necking embrace that looks almost snake-like. This continues on the land. The male has prepared a seaweed nest in advance, which he then shows to the female.
After mating, which usually occurs between the months of May to October, the females lay eggs. They have an incubation period of one month. Both parents take responsibility for the newly-hatched chicks for up to nine months. The female will abandon the male and chick if there is not sufficient food.
Waved Albatross
The Waved Albatross is the largest of the Galápagos bird species, and the males are larger than the females. It is colored with brown parts on the top, including wings that are gray with waved bars across them. It is these waved bars that give the bird its name. The neck and nape are white and cream colored. The bill is yellow. This bird can have a wingspan of up to 2.5 meters when fully grown.
These birds only mate in the Galápagos, though they also reside in northern Peru and on the Ecuadorian coast. Around late March they return to Española to mate. After their mate arrives, they perform an intricate courting dance that can be observed between mid-April and sometimes as late as November. The dance involves moving their necks up and down and practicing a waddle dance. The beaks are pointed toward the sky and they make a strange sound.
An interesting sight is to watch the birds taking off. They will run along the platform next to the cliff on Española and then jump to catch the winds.
Darwin’s Finches
When observing Darwin’s Finches, it is sometimes hard to understand how Charles Darwin could ever have developed a theory of evolution based on the differences between these birds. They are difficult to tell apart, and the differences relate to their beaks and feeding behavior. All of Darwin’s thirteen species of finches are the size of a sparrow. They all have brown, black, green or grayish plumage and short wings. The finches can be found across all islands.
The finches differ significantly in their feeding habits. While some eat insects, others feast on cactus. Other species prefer leaves and some eat seeds. Some of the species eat insects from the backs of reptiles, while others eat the larvae of insects. One particularly interesting finch has been given the nickname of “vampire” finch, since it likes to drink the blood of the Red Footed or Nazca Boobies.
The finches begin to mate around February time. This is after the first big rainfall of the season. To woo the female, the male creates a nest made from a variety of materials, including sticks, feathers and grass. The female lays between two and five eggs and the male and female work together to incubate the chicks during the early days.
Greater Flamingo
Galápagos flamingos are pink colored like their relatives elsewhere in the world. This is due to the color of the food that they eat—the crustaceans and shrimp larvae that they feed on have carotene pigments within them. The Greater Flamingo has gray or pink legs and webbed feet. The primary feathers of this bird are black. The beak is pink and black. Unusually, the Greater Flamingo is said to have arrived from the Bahamas as the result of a strange storm. They were not strong enough to return, so they stayed.
The Greater Flamingos are found on Floreana (Punta Cormorant), Santa Cruz (Las Bachas Beach) and at Puerto Villamil on Isabela. mates in July and August. The males perform a line dance to attract the females, and pairs are monogamous. The nests are cone shaped and tall. The chicks hatch in September and October. Juveniles are born white and turn pink after around three months when they have been eating. Their beaks are straight at birth and curve later in life.
Reptiles
Galápagos Giant Tortoise
The Galápagos Giant Tortoise is the species that gave the Galápagos its name. Galápagos comes from the Spanish saddle that is of the same shape to the shell of a couple of different species of the tortoises.
Galápagos Giant Tortoises are gigantic. They can weigh up to 250 kilograms and may grow to 1.5 meters. They eat a wide variety of plants, and the volume of food that they have dictates their size. All of the different eleven species of Galápagos Giant Tortoise have evolved in a unique way due to the differences in their habitats.
The tortoises are thought to live up to 150 years of age, with female tortoises beginning to engage in sexual activity at around the age of 25. During the mating periods, the tortoises migrate to lower ground and dig a hole for their eggs. The eggs are covered over and they incubate for up to 140 days before hatching.
One of the best places to view the giant tortoises is in the Santa Cruz highlands.
Marine Iguana
Marine Iguanas are mainly black and gray in color but many of them have a red and green coloring on their backs. This is the result of the food that they eat—the algae they consume has dyes within it. The Marine Iguana is unique in that it is the only type of lizard that takes to the sea. Their physical characteristics have evolved for this, with long tails, webbed feed and a flat head. They will swim up to 10 meters deep for food. After swimming, they will lay in the sun to warm up.
The Marine Iguana’s ability to swim is an evolution that developed after the iguanas arrived on the islands. When they first arrived they were land-based. They learned the ability to swim over a long period of time.
The Marine Iguana is polygamous. The female will mate with many males, and eggs are laid during the early months of the year. Eggs take three months to incubate. Once hatched, those that survive may live for 40 years. However, they face many threats while they are young from predators.
Land Iguana
There are three types of Land Iguanas in the Galapagos: the common Land Iguana, the Santa Fé Land Iguana and the Isabela Pink Iguana. The former two species are a similar looking yellowish color. Land Iguanas live for around 45 years and some of them interbreed. The Santa Fé Land Iguana is recognizable by its lighter color and more dominant crest. They feed in a small sized area, and mainly eat food that derives from the opuntia cactus.
The males attract the females during the mating season by turning a bright red color. They are aggressive about their territory during this time. Following mating, the females will lay up to eight eggs in nests that they have built underground. The eggs are usually laid between the months of January and March. Around seventy percent of young Land Iguanas survive and make it to adulthood.
Due to their small feeding areas, Land Iguanas can be very easily affected by changes to climate in the area. Another threat that they face is the predation from the Galápagos Hawk.
Mammals
Galápagos Sea Lion
The Galápagos Sea Lion is located through all the Galápagos Islands. One of the most fun treats that a visitor snorkeling might have is to play with the young in the sea. Travelers should take care not to run into the males (bulls) in the sea though, as these can be rather aggressive and territorial. The life span of a sea lion is approximately fifteen years.
Male sea lions run harems that may be made up of around 20 females (cows). They fiercely protect their area since there is limited space. Those males who do not run a pack have to leave and will gather in male-only sites until they are ready to challenge a male for his ladies.
Reproduction commonly occurs between June and November, though it can differ on the different islands. Sea lions practice a water birth for their pups. The gestation cycle is complicated. Females have a pup every two years. The birth cycle is annual. Ninety percent of the pups born are female. They are reared in groups of pups and kept together for around five months. After this, the pups are capable of hunting. However, they do not fully mature for three to five years.
Galápagos Fur Seal
The Galápagos Fur Seal was endemic to the islands, but now a colony is located in northern Peru. They grow between 1.2 to 1.5 meters in length and males can weigh up to 64 kilograms. They do not spend very much time in the sea compared to their other seal counterparts. They prefer to live on rocky shorelines and they live for approximately twenty years.
The mating season runs from mid-August to mid-November. The females will stake out a territory for themselves. The pups will nurse for longer than most other seal species, with mothers taking care of their young for three years. Sometimes a pup might be more independent at one or two years old. Pups need to take care when their mothers leave to go and find food (sometimes for up to four days in a row), to ensure that they do not lose their mother’s territory.
One of the threats to this fur seal species is the effect of the El Niño phenomenon, which can cause food shortages, and this sometimes causes pups to die. They hunt at night when it is easier to catch their food and they eat fish, feeding near the shoreline. They have been observed at great depths.
