http://www.ck12.org Chapter 11. Understanding Biodiversity: Animals: Mammals
right to the skull, while other vertebrates have a different bone connecting them. There are three small bones the carry
sound waves through the ear. The diaphragm creates a barrier between the heart and the lungs from the abdominal
cavity.
Behavior
The behavior of the sea otter is unknown to most. Although there have been sea otter taggings, sea otters have very
confusing behavior, being passive in certain situations and aggressive in others. The sea otter is diurnal, meaning
they are active during the day and sleep at night. Sea otters sleep on the water and hold hands when they sleep so
that they won’t float away from each other. They are solitary during the day, but in Alaska they can be seen in groups
up to 2,000 otters at a time at night. Collecting food takes place under water. When gathering food, they dive down
to the bottom of the ocean and collect clams and sea urchins. They then swim back to the surface and lay on their
back, using a rock to crush the shell of their food. Instead of fighting their predators, they run and hide in the safety
of the kelp forests. Then they climb up to land and keep safe there.
Their territories are divided by sex, and they only come together when mating season comes along. During mating
season, the males have multiple partners. Mating takes place in the water. During mating, the male bites the female’s
nose, leaving scars, and pushes her head underwater until they are finished. The average sea otter is pregnant for
4-12 months. Usually, her pup weights around 1.4-2.3 kg (3-5 lb). Usually nursing lasts around 6-8 months. Her
pup will usually drink from her two lower nipples as they are floating across the water. The pup will be fully weaned
at the age of 6-8 months. Sadly, only 25% of the pups last their first year or life. If so, their mothers will carry the
pup’s body for months on end after it death.
References
- Enhydra lutris —Overview,The Encyclopedia of life,http://eol.org
- http://www.ck12.org/biology/Prokaryotic-and-Eukaryotic-Cells/lesson/Prokaryotic-and-Eukaryotic-Cells/
- http://naturebytesvideo.com/
- http://www.seaworld.org/animal-info/animal-bytes/animalia/eumetazoa/coelomates/deuterosto4mes/chordata/c
raniata/mammalia/carnivora/sea-otter.htm - Sea Otter Facts, http://www.seaotter-sealion.org/seaotter/factsseaotter.html.
- Elbroch, Mark, and Kurt Rinehart. Behavior of North American Mammals,Boston: Houghton Mifflin Har-
court, 2011. - Wolkomir, Richard,The Fragile Discovery of California Sea Otter.National Geographic Volume #187 March
12,2013: Pages 43- 61.
Attribution
Authors
- Alexa Lawrence
- Zoe White
Supervising Faculty
- Amy Huff Shah