The Amazing Galapagos Sea Lion
Here are just a few facts about the amazing Galapagos sea lion.
Galapagos Sea Lion – Population Overview
The Galapagos sea lion is a mammal that generally breeds in the Galapagos Islands, even though some mating colonies also happen on Isla de la Plata just from mainland Ecuador.
The most recent estimates of Galapagos sea lion, conducted in November 2001 by the
Charles Darwin Foundation found around 14,000 -16,000 Galápagos sea lions. This is down from 40,000 in 1977.
Sea lions are members of the seal family. And Galapagos sea lions are members of the eared seal family – having an exterior ear canal. Galapagos sea lions aren’t ‘true’ seals, because they are able to turn their hind flipper under their pelvic girdle. This allows them to basically run across land.
Galapagos Sea Lion – Males and Females
There is a huge size difference between male Galapagos sea lions and females. the males can weigh up to four times that of females. Male Galapagos sea lions have a dominant bump on the forehead, making them easy to tell apart from the females.
All Galapagos sea lions have brown or gray hair, females generally being truly a lighter hue than guys, and pups being chestnut brownish. They are savy hunters and sardines are their main food source.
Galapagos Sea Lion – Diving and Hunting
Galapagos Sea Lions are able to dive to depths as high as 350 meters and can stay underwater for ten minutes. They spend a whole lot of their own time resting on seashores or playing, and tend to be curious of any visitors.
The Galapagos sea lions has diurnal feeding habits. Diurnality is a form of plant or animal behavior characterized by activity during the day, with a period of sleeping, or other inactivity, at night.
Galapagos Sea Lion – Breeding
Males have a tendency to “carry territories” on shorelines where females live, instead of holding immediate harems. Like many mammalls, the more dominant the male is, the greater territory he lays claim to. This normally translates into more females for him to breed with. Galapagos Sea Lion males aggressively protect these territories from other male competitors. Bachelor male herds are not uncommon for males that can’t secure territory.
The mating season usually occurs between July and Dec, but may vary from island to island. Females enter into oestrus 3 to 4 weeks after pupping, when they’ll partner with the males.
After the pups are born they will bond with their mom for the first week. This helps in creating a unique call to tell apart it from the others. The mom then begins to forage by day and suckle the puppy at night, until the 5th week when the puppy molts its baby jacket and starts feeding itself. Pups remain reliant on their moms for the first time of the life, being weaned normally around a year old.
Galapagos Sea Lion Locations
In Galapagos, they are located on Plaza Sur Island, Mosquera Island, Gardner Bay in Espanola, Rabida Island (with a bachelor colony) and Puerto Egas on Santiago.Galapagos sea lions stay static in the Galapagos Islands throughout the year, rarely migrating.
Galapagos Sea Lion Risks
Their natural predators are sharks and killer whales, but the key threat to their survival is human activity. Recent studies have concluded that human activity is the main risk to sea lion populations. This includes oil spills, fishery interactions, and illegal hunting. Natural events such as the 1982-1983 and 1997-1998 El Niños also caused large reductions in populations, and diseases are being monitored to try to prevent negative impacts on the islands’ populations.
In July 2001, fifteen subadult and adult Galápagos sea lions, four females and eleven males ranging from 4 to 12 years old, were illegally killed on San Cristóbal Island, near La Lobería (Salazar 2001, Salazar and Edgar 2001). This illegal hunt may be linked with the Asian black market for aphrodisiac products, since all male reproductive organs were removed by the hunters (Salazar 2001, Salazar and Edgar 2001).
Other animal facts in our Animals A-Z.