The Lion of the Sea

Known for their intelligence, playfulness, and noisy barking, the California sea lion, or Zalophus californianus, live on Rocky beaches and in coastal waters on the western coast of North America from the Baja California peninsula in Mexico to British Columbia.

screen-shot-2016-11-26-at-5-11-04-pm

Photograph taken from: http://kids.nationalgeographic.com/animals/california-sea-lion/#sea-lion-map.jpg

IMG_5540.JPG

Photograph taken by me at the Brookfield Zoo

California sea lions are sexually dimorphic. Their body length ranges from: males 6.5 to 9 feet and females 5 to 6.5 feet. In addition, their weight ranges from: males 450 to 1200 pounds and females 110 to 350 pounds. Although the pups are born with a dark, black-brown coat, the adult California sea lions’ color ranges from chocolate brown in males to a lighter, golden brown in females.

dimorphism.jpg

Photograph taken from: http://www.reed.edu/biology/courses/BIO342/2014_syllabus_old/web.html

6a010535647bf3970b01774394ca8f970d-500wi

Photograph taken from: http://www.zooborns.com/zooborns/2012/07/sea-lion-pups-make-waves-at-belfast-zoo.html

img_5541-3

Photograph taken by me at the Brookfield Zoo

California sea lions have a “dog-like” face. Although the California sea lions’ average lifespan in the wild is up to 17 years, at around five years of age, the males develop a bony bump on top of their skull called a sagittal crest. Although the adult male California sea lions have a raised forehead (called the cranial or sagittal crest like just mentioned), females have a lower, smoother forehead.

male-female-csl-robinlindsey-websiteblue-2

Photograph taken from: http://www.sealsitters.org/marine_mammals/sea_lions.html

screen-shot-2016-11-26-at-7-16-54-pm                                         Photograph taken by me at the Brookfield Zoo
img_1225These members of the walking seal family have external ear flaps, a think fur, and large fore flippers (furless and clawless) that they can use to “walk” on land. These animals use their fore flippers in an up-and-down, wing-like motion to powerfully propel themselves through the water. In the water, a sea lion extends its hind flippers and uses them to help steer which enable them to make quick, sharp turns. On land, a sea lion can rotate its hind flippers underneath the pelvic girdle enabling it to walk on all fours. Unlike the fore flippers, the middle three digits on their hind flippers have noticeable nails that are used to groom their fur. Fun fact: the weight of their bodies can actually be supported by their flippers!

Watch the video and pay close attention to their fore and hind flippers: https://www.youtube.com/watch?v=cqXiBEkK4y8. It seems as if they’re “flying” through the water!

The lefthand side shows the sea lions fore flippers and the righthand side shows the sea lions hind flippers. Photographs taken from: https://seaworld.org/en/animal-info/animal-infobooks/california-sea-lion/physical-characteristics

California sea lions are well adapted for life in the water. Their body is smooth and streamlined. Their torpedo body shape lets them swim with little resistance. Their nostrils are normally closed to keep out water. Therefore, they must voluntarily flex small muscles to open their nostrils to breathe. Like all pinnipeds, sea lions are warm-blooded, so they have a thick coat of fur and a heavy layer of fat under their skin to insulate their bodies from the chill of marine waters.

Gal-UW-Sealion10.jpgPhotograph taken from: http://www.oceanlight.com/santa_barbara_island_photo.html

Fla-me-ln-sea-lion-pup-stolen-20150420un fact: the California sea lion is faster than any other sea lion or seal in the world- they can reach speeds of about 25 miles per hour! In addition, they can dive to depths of of over 1000 feet. By slowing down their heart rate, they have the ability to stay underwater for nearly ten minutes without breathing. Being opportunistic eaters, this ability actually gives them an edge in the pursuit of the fish, squid, octopus, herring, rockfish, mackerel, and small sharks that make up their primary diet. In turn, however, sea lions are preyed upon by Orcas (killer whales) and great white sharks.

Please watch video attached above to analyze how deep these animals can dive for long periods of time.

Screen Shot 2016-11-26 at 7.16.42 PM.png

Photograph taken by me at the Brookfield Zoo

Finally, California sea lions are listed as of “least concern” on the IUCN Red List (International Union for Conservation of Nature and Natural Resources). Therefore, these animals are not threatened in the wild as they are protected by the United States Marine Mammal Protection Act of 1972.

img_1174img_1173img_5543img_1214b99329e7-1152-4324-94fd-2ec7ed529576

Photographs taken by me at the Brookfield Zoo

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s