The Galapagos Penguin (Spheniscus mendiculus) is a penguin endemic to the Galápagos Islands. It is the only penguin to live on the equator and can survive due to the cool temperatures resulting from the Humboldt Current and cool waters from great depths brought up by the Cromwell Current. Its nearest relatives are the African Penguin, the Magellanic Penguin and the Humboldt Penguin.
The Galápagos Penguin occurs primarily on Fernandina Island and the west coast of Isabela Island, but small populations are scattered on other islands in the Galápagos archipelago. The Galapagos Penguin is one of the smallest penguins. It is the only penguin to cross the Northern Hemisphere which means they live farther north than any other warm weather penguin. 90% of the Galapagos Penguins live among the western islands of Fernandina and Isabela, but they can also be seen on Santiago, Bartolome, northern Santa Cruz, and Floreana.
The penguins stay in the archipelago. They stay by the Cromwell Current during the day since it is cooler and return to the land at night. The average size for the penguins is 48-50 cm (19-20 in) and 2.5 kg (5.5 lbs). They have a black head with a white border running from behind the eye, around the black ear-coverts and chin, to join on the throat. They have blackish-grey upperparts and whitish underparts, with two black bands across the breast, the lower band extending down the flanks to the thigh. Juveniles differ in having a wholly dark head, greyer on side and chin, and no breast-band. The female penguins are smaller than the males, but they are still a lot alike.
They eat small schooling fish, mainly mullet, sardines, and sometimes crustaceans. They only go search for food during the day and normally within a few kilometers of their breeding site. They depend on the cold nutrient-rich currents to bring them food.
The Galapagos Penguins breed as many as three times a year, since they don’t have a specified breeding season. Because of this, they are able to choose when to breed, and they ultimately decide this depending on food supplies. Before they breed, the penguins molt, and they may do this twice a year. While the birds are molting, they usually stay out of the water. They are able to go to the sea for food rather than starve though since the water is so warm in their area. Since they molt right before breeding, they are sure that they will not starve during the molting process. Granted, that may mean that there is not enough food during the breeding season, but the survival of the adult penguins is more important than the younger ones since they are the ones that make sure the species does not go extinct.
Because of the Galapagos Penguin’s smaller size, it has many predators. On land, the penguins must keep an eye out for crabs, snakes, owls, and hawks, while in the water they must avoid sharks, fur seals, and sea lions. They face many hazards due to humans, as well as the hazards of unreliable food resources and volcanic activity. Illegal fishermen interrupt the penguins’ nesting area by knocking down mangrove trees, and they are often caught in fishing nets by mistake. Much balance has to take place to ensure that the Galapagos Penguins do not become extinct.
Most nests are seen between May and January. The nests are made within 50 meters (164 ft) of the water on the shore. Adults stay near the breeding area during the year with their mate that they have chosen for life. When the penguins are breeding, incubation takes 38–40 days with both parents helping out. After thirty days of the chicks being born and both parents sharing responsibility of taking care of them, the chicks have feathers that are brown above and white below. The purpose of this is to protect the chicks from the strong sun more so than keeping them warm.
The Galápagos Penguin mates for life. It lays one or two eggs in places such as caves and crevices, protected from direct sunlight, which can lead to the eggs overheating. One parent will always stay with the eggs or chicks while the other is absent for several days to feed.
The parents usually only rear up one child. If there is not enough food available, the nest may be abandoned. The temperature at the islands stays between 15-28 degrees Celsius (59-82°F). During the El Niño seasons, the penguins put off breeding since the food becomes short from the effects of El Niño; this in turn makes the chances of raising offspring successfully unfavorable when compaired to the chances of dying in the attempt. They usually breed when the sea surface temperature is below 24 degrees Celsius (75°F) which results in more food for them.
The strong sun is the main problem for the penguins in the Galapagos Islands. The main way they cool off is by going into the water, but they have had many behavioral adaptations because of all the time they spend on land in the warm weather. There are two ways that help cool the penguin in the warmer weather on land. One is by stretching out their flippers and hunching forward to keep the sun from shining on their feet since they can lose heat from their flippers due to the blood flow there. They also pant because they can cool off from the evaporation from the throat and airways.
The species is endangered, with an estimated population size of around 1,500 individuals in 2004, according to a survey by the Charles Darwin Research Station. The population underwent an alarming decline of over 70% in the 1980s, but is slowly recovering. It is therefore the rarest penguin species (a status which is often falsely attributed to the Yellow-eyed penguin). Population levels are influenced by the effects of the El Niño Southern Oscillation, which reduces the availability of shoaling fish, leading to low reproduction or starvation. However, anthropogenic factors (e.g. oil pollution, fishing by-catch and competition) may be adding to the ongoing demise of this species.
On Isabela Island, the introduced cats, dogs and rats attack penguins and destroy their nests. When in the water, they are preyed upon by sharks, fur seals, and sea lions.
Isabella
Shaped like a sea horse, Isabela is the largest of the the islands in the Galapagos, more than 4 times larger than Santa Cruz the next largest. Isabela is 80 miles (100 km) in length and though it is remarkably beautiful it is not one of the most visited islands in the chain. Its visitor sites are far apart making them accessible only to faster boats or those with longer itineraries. One of the youngest islands, Isabela is located on the western edge of the archipelago near the Galapagos hot spot. At approximately 1 million years old, the island was formed by the merger of 6 shield volcanoes - Alcedo, Cerro Azul, Darwin, Ecuador, Sierra Negra and Wolf. Five of the six volcanoes are still active (the exception is Ecuador) making it one of the most volcanically active places on earth. Visitors cruising past Elizabeth Bay on the west coast can see evidence of this activity in the fumaroles rising from Volcan Chico on Sierra Negra. Two of Isabela's volcanoes lie directly on the equator - Ecuador and Volcan Wolf. Volcan Wolf is the youngest of Isabela's volcanoes and at 5,600ft (1707 m) the highest point in the Galapagos. Isabela is known for its geology, providing visitors with excellent examples of the geologic occurrences that have created the Galapagos Islands including uplifts at Urbina Bay and the Bolivar Channel, Tuft cones at Tagus Cove, and Pulmace on Alcedo. Isabela is also interesting for its flora and fauna. The young island does not follow the vegetation zones of the other islands. The relatively new lava fields and surrounding soils have not developed the sufficient nutrients required to support the varied life zones found on other islands. Another obvious difference occurs on Volcan Wolf and Cerro Azul, these volcanoes loft above the cloud cover and are arid on top. Isabela's rich animal, bird, and marine life is beyond compare. Isabela is home to more wild tortoises than all the other islands. Isabela's large size and notable topography created barriers for the slow moving tortoises; apparently the creatures were unable to cross lava flows and other obstacles, causing several different sub-species of tortoise to develop. Today tortoises roam free in the calderas of Alcedo, Wolf, Cerro Azul, Darwin and Sierra Negra. Alcedo Tortoises spend most of their life wallowing in the mud at the volcano crater. The mud offers moisture, insulation and protects their exposed flesh from mosquitoes, ticks and other insects. The giant tortoises have a mediocre heat control system requiring them to seek the coolness of the mud during the heat of the day and the extra insulation during the cool of the night. On the west coast of Isabela the nutrient rich Cromwell Current upwelling creating a feeding ground for fish, whales, dolphin and birds. These waters have long been known as the best place to see whales in the Galapagos. Some 16 species of whales have been identified in the area including humpbacks, sperms, sei, minkes and orcas. During the 19th century whalers hunted in these waters until the giant creatures were near extinction. The steep cliffs of Tagus Cove bare the names of many of the whaling ships and whalers which hunted in these waters. Birders will be delighted with the offerings of Isabela. Galapagos Penguins and flightless cormorants also feed from the Cromwell Current upwelling. These endemic birds nest along the coast of Isabela and neighboring Fernandina. The mangrove finch, Galapagos Hawk, brown pelican, pink flamingo and blue heron are among the birds who make their home on Isabela. A colorful part to any tour located on the western shore of Isabela, Punta Moreno is often the first or last stopping point on the island (depending on the direction the boat is heading). Punta Moreno is a place where the forces of the Galapagos have joined to create a work of art. The tour starts with a panga ride along the beautiful rocky shores where Galapagos penguins and shore birds are frequently seen. After a dry landing the path traverses through jagged black lava rock. As the swirling black lava flow gave way to form craters, crystal tide pools formed-some surrounded by mangroves. This is a magnet for small blue lagoons, pink flamingos, blue herons, and Bahama pintail ducks. Brown pelican can be seen nesting in the green leaves of the mangroves. You can walk to the edge of the lava to look straight down on these pools including the occasional green sea turtle, white-tipped shark and puffer fish. This idyllic setting has suffered from the presence of introduced species. Feral dogs in the area are known to attack sea Lions and marine iguanas.
Galapagos Islands
The Galápagos Islands (official name: Archipiélago de Colón; other Spanish names: Islas de Colón or Islas Galápagos) are an archipelago of volcanic islands distributed around the equator in the Pacific Ocean, some 900 km west of Ecuador. It is a UNESCO World Heritage site: wildlife is its most notable feature. Because of the only very recent arrival of man the majority of the wildlife has no fear of humans and will allow visitors to walk right up them, often having to step over Iguanas or Sea Lions.The Galápagos islands and its surrounding waters are part of a province, a national park, and a biological marine reserve. The principal language on the islands is Spanish. The islands have a population of around 40,000, which is a 40-fold expansion in 50 years. The islands are geologically young and famed for their vast number of endemic species, which were studied by Charles Darwin during the voyage of the Beagle. His observations and collections contributed to the inception of Darwin's theory of evolution by natural selection.
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