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A curious Galapagos Sealion (covered in sand!) waddling up for a closer look on Chinese Hat Island


Galapagos Sea Lion
The Galapagos Sea Lion (Zalophus wollebaeki) breeds on the Galapagos Islands and – in smaller numbers – on Isla de la Plata (to Ecuador). Being fairly social, and one of the most numerous species in the Galapagos archipelago, they are often spotted sun-bathing on sandy shores or rock groups or gliding gracefully through the surf. Their loud “bark”, playful nature, and graceful agility in water make them the “welcoming party” of the islands. They are lightly smaller than their Californian relatives, Galapagos Sea Lions range from 150 to 250 cm in length and weigh between 50 to 400 kg, with the males much larger than females. Adult males also tend to have a thicker, more robust neck, chest, and shoulders in comparison to their slender abdomen. Females are somewhat opposite males with a longer, more slender neck and thick torso. Once sexually mature, a male’s sagittal crest enlarges, forming a small, characteristic bump-like projection on their forehead. Galapagos Sea Lions, compared to California sea lions, have a slightly smaller sagittal crest and a shorter muzzle. Adult females and juveniles lack this physical characteristic altogether with a nearly flat head and little or no forehead. Both male and female sea lions have a pointy, whiskered nose and somewhat long, narrow muzzle. The young pups are almost dog-like in profile. Another characteristic that defines the sea lion are their external ear-like pinnae flaps which distinguish them from their close relative in which they are often confused with, the seal. The fore-flippers have a short fur extending from the wrist to the middle of the dorsal fin surface, but other than that, the flippers are covered in black, leathery skin. Although somewhat clumsy on land with their flippers, sea lions are amazingly agile in water. With their streamline bodies and flipper-like feet, they easily propel themselves through crashing surf and dangerously sharp coastal rocks. They also have the ability to control their flippers independently and thus change directions with ease and have more control over their body on land. When wet, sea lions are a shade of dark brown, but once dry, their color varies greatly. The females tend to be a lighter shade than the males and the pups a chestnut brown. Born with a longer, brownish-black lanugo, a pup's coat gradually fades to brown within the first five months of life. At this time, they undergo their first molt resulting in their adult coat. Feeding mostly on sardines, Galapagos Sea Lions sometimes travel ten to fifteen kilometers from the coast over the span of days to hunt for their prey. This is when they come into contact with their biggest predators: sharks and killer whales. Injuries and scars from attacks are often visible. Galapagos 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 come into contact with human waste, fishing nets, and hooks. They occupy many different shoreline types from steep, rocky cliff sides to low-lying sandy beaches. To avoid overheating during the day, sea lions will take refuge from the sun under vegetation, rocks, and cliffs, and wade into tidal pools. Not only are sea lions social, they are also quite vocal. Adult male Galapagos Sea Lions often bark in long, repeated sequences that are loud and distinctive. Females and juveniles do not produce this repetitive bark, but both sexes and the younger pups will growl. From birth, a mother sea lion recognizes her pup’s distinct bark and can pin point it from a crowd of thirty or more barking sea lions. On land, sea lions form colonies at their hauling-out areas. Adult males known as Bulls are the head of the Colony, growing up to 7 ft (2 m) long and weighing up to 800 lb (363 kg). As males grow larger, they fight to win dominance of a harem of between 5 and 25 cows and the surrounding territory. Swimming from border to border of his colony, the dominant bull jealously defends his coastline against all other adult males. While patrolling his area, he frequently rears his head out of the water and barks, as an indication of his territorial ownership. The average dominant bull holds his territory for only a few months, until he is challenged by another male. On land, these fights start by stretching out the neck and barking in attempt to test each other’s bravery. If this isn’t enough to scare the opponent off, they begin pushing each other and biting around the neck area. If males weren’t equipped with a thick, muscular neck, their vital organs would be easily damaged during these fights. Blood, is often drawn, however, and many male sea lions have battle scars due to these territorial competitions. Losers are dramatically chased far from their territory by the new dominant bull with much splashing. Because there is

Galapagos Penguins swimming off Chinese Hat Island.

Galapagos Penguin
The Galapagos Penguin (Spheniscus mendiculus) is a penguin endemic to the Galapagos 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 Galapagos Penguin occurs primarily on Fernandina Island and the west coast of Isabela Island, but small populations are scattered on other islands in the Galapagos 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 Galapagos 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 Nino seasons, the penguins put off breeding since the food becomes short from the effects of El Nino; 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 th