Mammals

 

Mammals

There are relatively few species of native land mammals in the Galapagos because of the distance and difficulty of the journey there from the mainland. Today, six native species can be found on land; two species of rice rat, two species of bat, the Galapagos fur sea and the Galapagos sea lion. You are unlikely to see native rats or bats during your adventure, but you are very likely to encounter a great number of Galapagos sea lions and even some of their less gregarious cousins, Galapagos fur seals.

MEET THE MAMMALS OF THE GALAPAGOS

Galapagos Sea Lion
This photogenic and curious subspecies of the California sea lion is one of the first animals you’re likely to encounter in the Galapagos. They love snoozing on docks and lazing on benches near areas where tourists boats disembark. And with a population of about 50,000, they are a common sight on beaches and rocky shorelines throughout the archipelago.

Galapagos sea lions are the largest mammal found on land here – territorial bulls can weigh up to 550 pounds and can be distinguished from females by the large bump on their heads and thick necks. On land, sea lions congregate in either harems or bachelor groups. A harem consists of up to thirty females (who are free to come and go as they please), juveniles, pups, and one dominant bull, who spends most of his time and energy patrolling nearby waters fending off rival bulls. Because it’s exhausting work, a bull’s defense of his harem is usually short-lived, often lasting just a few days and generally no more than a few months. Harems are typically found in the most desirable beach locations, while bachelor groups (comprised of young males) are usually situated atop rocky cliffs, near inland lagoons and in other more difficult to reach spots.

One of the most endearing sites in the entire archipelago is a sea lion pup snoozing or cavorting on the beach. Females, who become sexually mature around the age of five and can live for up to 20 years, give birth to a single pup each year and will rear it for one to three years. For this reason, it’s not uncommon to see a mother suckling two pups of different ages. Mothers stay with newborn pups for a few days before venturing into the ocean for fish, squid, octopus and crustaceans. When this happens, the pups head to a shallow nursery where they are supervised and protected by another female from sharks and other predators. Mothers and pups recognize each other by smell and the sound of their barks. Sea lion pups venture into the water and start hunting on their own at about five months and are weaned after about a year.

Female sea lions and pups can be curious and friendly, especially in the water, and are renowned for playfully whizzing and spinning around divers and snorkelers. Bulls, on the other hand, should be given a wide berth, as they have been known to bite when approached too closely.  Watch this video of an NHA guest having a blast swimming with friendly sea lions:

Galapagos Fur Seal
Galapagos fur seals aren’t actually true fur seals, but a species of fur sea lion. They are similar in appearance to Galapagos sea lions and are often mistaken for them. It is actually pretty easy to distinguish between the two if you know what to look for; fur seals are typically quite a bit smaller and have broader, shorter, more bear-like heads. They also have larger front flippers (better for climbing up rocks), more protuberant eyes and ears, and are much furrier than Galapagos sea lions.

Fur seals prefer cooler, shadier, rockier areas with easy access to deep water, instead of the direct sunlight, open stretches of beach and shallow water that sea lions prefer. Because of this, fur seals are seen less frequently than sea lions, leading many visitors to mistakenly think that sea lions are much more abundant than fur seals. In truth, their numbers are about the same.

In spite of their differences, fur seals have a lot in common with their sea lion cousins when it comes to social and breeding behavior. The males of both species protect harems of females from rival males. The breeding season lasts from August to November. Females may give birth each year, but mortality among pups is high and it’s unusual for a mother to successfully raise more than one pup every two years. Fur seals hunt for fish and squid at night, often diving to depths of more than 300 feet, taking care to avoid the sharks and killer whales that prey upon them.

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