Galapagos Wildlife
REPTILES
Marine Iguanas (Amblyrhynchus cristatus)
One of the most bizarre and unique reptiles of the Galapagos is the dark-hued marine Iguana, the only aquatic iguana in the world. They can swim to a depth of 20m, anaerobically lower their body temperatures to stay underwater for up to 1hr. at a time, and are able to rapidly discharge excess salt from their unusually square noses. The Galapagos marine iguana feeds almost entirely on algae (seaweed) that it finds between the tide-lines or below the sea's surface. Whether above or below the sea, the food consists of small red or green algae. It does not seem to be very choosy as to which species of algae it eats, except that it avoids the large brown seaweed Blossevillea.
Lava Lizards (Tropidurus spp)
Seven species of gray lava lizard are also unique to the islands. Females have eye-catching red-orange throats. They are very territorial, but most confrontation takes the form of bouncing up and down on the forelegs; fights between lizards are seldom serious but can be entertaining. Galapagos Snakes hunt for small reptiles and mammals. Prey includes lava lizards, grasshoppers, geckos and marine iguana hatchlings. They also feed on finch nestlings. In turn, the snakes are preyed upon by the Galapagos hawk, their only natural predator. They are very difficult to spot but are usually seen on the Galapagos Islands of Santa Fe and North Seymour islands.
MAMMALS
Sea Lions (Zalophus californianus)
The superstar mammal of the Galapagos is the Galapagos sea lion. Weighing up to 250kg, the lethargic giants occupy what seems like every open speck of beach on the islands, posing for tourists, surfing a wave, belching loudly, sliding through the water with one fin in the air, Although the sleek sea lions are generally playful, beware of the extremely territorial "beachmaster" machos (male bulls), which pace the shores guarding their harem of 20-30 female partners. Sea lions feed mostly on sardines (the cause of their bad breath), for which they may travel ten to fifteen kilometers out from the coast over the span of days to hunt. It is in deep water that sea lions encounter and must defend themselves from their only predators, sharks.
Fur seals (Arctocephalus galapagonesis)
Galapagos fur seals are the smallest pinnipeds. Adult bulls weigh about 70 kg, adult females about 28 kg. Pups are born with a smooth and silky skin to which fur develops around 6 months of age. This made them prime targets for hunters back in the 18th century. The Galapagos fur seal feeds mainly on cephalopods and small schooling fish. Feeding occurs mainly at night
MARINE LIFE
While a relatively limited number of species inhabits the terrain, the Galapagos’s waters teem with life. The 16 species of whale include the sperm, humpback, blue, and killer whales. The common and bottle-nosed are the most prevalent of the seven species of dolphin, which are concentrated off the west coast of Isabela and are frequently seen jumping and swimming in schools near the bows of tour boats. Twelve species of shark, including the hammerhead and black-tipped reef shark, and five species of rays also lurk in these waters. Many other species depend on the Galapagos marine life for their food, such as sea birds that eat fish, and the marine iguanas that feed on algae growing on the bottom of the sea.