Galapagos Sea Lion (Zalophus Californianus wollebaeki)

              

Class: Mammalia
Order: Pinnipedia
Family:    Otariidae
Size:    Length: 6 to 7 feet (1.8 to 2.1 m)
Weight: 220 to 850 pounds (110 to 390 kg)
Diet: Anchovies, herring, Pacific whiting, hake, salmon, squid and octopus
Distribution: Galapagos Islands, off the coast of Ecuador
Young:  1 per year
Animal Predators:  Killer whales, bull sharks and great white sharks
IUCN Status: Vulnerable
Terms: Young: Pup  Male: Bull  Female: Cow  Group: Colony
Lifespan: Up to 20 years in the wild, up to 30 years in zoos

 

Facts/Trivia:

·         The Galapagos sea lion is a subspecies of the California sea lion.

·         They belong to the family Otariidae, which means “little ears.”

·         They can swim at speeds of more than 18 miles (30 kilometres) per hour. 

 

Description

Galapagos sea lions have short, thick fur that appears light to chocolate brown when dry and dark brown or black when wet. Males tend to be slightly darker in colour as well as larger than females. They have a pointy muzzle, large dark eyes and stiff whiskers that are made of keratin and have nerves at the tips. They have a streamlined body, and long flippers. Males develop a slightly raised forehead between the ages of five to eight, that becomes lighter in colour as they age. 

 

Habitat

Galapagos sea lions live in the coastal waters and on the sandy beaches or rocks of the Galapagos Islands in the eastern equatorial Pacific, about 620 miles (1,000 km) west of Ecuador, South America. 

 

Feeding Habits

Galapagos sea lions feed on a variety of fish, including anchovies, herring, Pacific whiting, hake, salmon, squid and octopus. They eat 15 to 35 pounds (7 to 16 kg) of fish per day, swallowing smaller fish whole and breaking larger fish into chunks with their cone-shaped teeth. 

 

Reproduction

Female Galapagos sea lions give birth to a single pup (twins are rare) nine months after mating, then mate again approximately 10 days afterwards. They give birth on land, within a breeding colony that may contain up to 900 sea lions. Pups are born with their eyes open and can swim, although awkwardly, shortly after birth. They have dark brown or black coats that lighten gradually as they grow to adulthood. Pups are weaned between five and 12 months, but begin to eat fish at two months. Pups stay with their mothers for at least a year, before gradually finding their complete independence. 

 

Behaviour

Galapagos sea lions are playful, curious, social animals that live in groups or colonies while on land, sleeping next to and even on top of each other. They also sometimes sleep on their backs or on rocks with their heads hanging over the edge. They play together in the water, keeping to their groups (called “rafts” while in water), leaping out of the water and splashing together. They have a variety of vocalisations including barking, growling, squeaking, and honking. Galapagos sea lions have excellent eyesight and a highly developed sense of smell. 

 

Conservation

These sea lions are protected throughout their range. The population of Galapagos sea lions is currently estimated between 20,000 and 75,000. Another subspecies of the California sea lion is the Japanese sea lion,  Zalophus californianus japonicus, which once lived near Japan but is now believed to be extinct. The population of the Californian California sea lion, Zalophus californianus californianus, has been increasing at a rate of about five percent a year.

 

Sources

http://ourworld.compuserve.com/homepages/jaap/sealion1.htm#california

http://www.pinnipeds.fsnet.co.uk/species/zalophus.htm

http://www.onr.navy.mil/focus/ocean/life/sealion1.htm

http://ucs.orst.edu/~palaciod/zalgen.htm

http://www.pbs.org/safarchive/5_cool/galapagos/g23b_biology.html

http://animaldiversity.ummz.umich.edu/accounts/zalophus/z._californianus$narrative.html

http://www.darwinfoundation.org/marine/sealion.html