Group 3: Southern Sea Otter - Juliana De La Cruz

SOUTHERN SEA OTTER **(Enhydra lutris neresis)**

DESCRIPTION AND ECOLOGY

Southern sea otters are also known as California sea otters. They’re the smallest of marine animals and live between 15-20 years. Males usually weigh around 65 kg and measure about 4.5 ft while females weigh around 45kg and measure about 4ft. They use their hind limbs as flippers that allow them to swim and float for long periods of time. They have very little fat and no blubber, which makes it harder for them to store energy to use as thermal insulation. Their main insulation comes from heat trapped in the fur. They also eat around 25% of their body weight each day in order to produce energy and maintain a fast metabolism. Sea otters usually eat a wide variety of invertebrate animals and kelp. They are also essential for keeping healthy kelp forests along the coast.

GEOGRAPHIC AND POPULATION CHANGES

Southern sea otters usually live right off the West coast between Half Moon Bay at the North and Point Conception at the South.
The population was exploited almost to extinction in the 1970s and since then, the animal recount has varied between 1,250 and 2,300 per year (according to the 2003 Recovery Plan data). Their birth rate is pretty low given that females can only give birth to one pup per year. Female otters achieve sexual maturity at age 3, while male otters become sexually active at age 5.
Moreover, their death rate is the greatest cause for their decline, as opposed to migration. The main threats to the population are: habitat degradation, human causes, food limitation, pollution and infectious disease caused by immune deficiencies or elevated parasite or pathogen exposure. These infectious diseases are also the main cause for the slow growth rate of the species.

Map on the right was taken from the Recovery Plan document by the US Fish and Wildlife Service

This image to the left, however, was taken from the Los Angeles Times and shows more accurate information from a census conducted in May 2008 by the U.S. Geological Survey and the California Department of Fish and Game.

In order for the southern sea otters to be delisted as a threatened species their population must reach at least 3,090 individuals.

LISTING DATE, TYPE AND CAUSE OF LISTING

The southern sea otter was listed as threatened under the Threatened and Endangered Species Act in 1973. Since then, there have been quite a few revisions made to their Recovery Plan; the last one being done in 2003.
According to the Recovery Plan, they were listed as threatened because of their small size, limited distribution, and potential jeopardy to the remaining habitat and animals due to oil spills.

MAIN THREATS TO ITS CONTINUED EXISTENCE

- Entanglement in fishing gear and fish trap fisheries (net fisheries)
- Effects of oil spills: the probability of sea otters dying after contact with oil is no less than 50%.
- Disease: infectious diseases as a result of parasites and microbes are responsible for about 40% of the deaths of the animals obtained for the salvage program.
- Growth rate is no larger than 5% each year.
- Pollutants and contaminated drainage that gets into the water

DESCRIPTION OF RECOVERY PLAN

Some of the actions that have been undertaken as a result of the Recovery Plan are the following:
-Management of fisheries in order to protect sea otters from incidental take. (This has been supported by the California Department of Fish and Game and by a legislation enacted by the California State Legislature.)
-Control in the use of gill and trammel nets as well as in the use of fish traps.
-Management of large vessel trafficking that can disrupt their habitats.
-Creation of the Oiled Wildlife Care Network: an organization that responds to protect wildlife in case of an oil spill.
-Development of a translocation plan established for the recovery and growth of sea otters. They translocated a group of sea otters to the San Nicolas Island with hope that they would adapt to the new habitat and reproduce more quickly in order to increase the population growth. However, the plan was not successful as some sea otters died and others went back to the mainland.
-Study of the sea otter population in order to have more insight on their behavior and the amount of individuals alive. The southern sea otters would become endangered if the population size is reduced to 500 individuals.

WHAT CAN YOU DO?

- Help educate people on the importance of conserving sea otters by donating to the organization “Adopt a Sea Otter” or to the “California Sea Otter Fund”
- Dispose of hazardous waste properly and use nontoxic products to prevent these from getting into the oceans
- Don’t litter or contaminate storm drains
- Be conscious of everything you put down your drains
- Help clean up the beaches
- Be aware of oil spillage from your car so that it doesn’t end up in the water
- Be careful when doing recreational fishing so that sea otters don’t get caught up in the gear
- Speak up and stay informed

Sea otters have the same right of survival as we do. So if you would not like a future without them, please do something about it and help in any way you can.

OTHER RESOURCES

In order to donate, become involved with organizations that advocate for sea otters or to simply stay informed, please visit the following websites:

- http://www.montereybayaquarium.org/animal-guide/marine-mammals/southern-sea-otter?gclid=CKj689TJx9ACFZFefgodNuwBsg
- http://www.biologicaldiversity.org/species/mammals/sea_otter/index.html
- http://www.defenders.org/sea-otter/how-you-can-help
- http://seaotters.org/pdfs/howcanihelp.pdf
- http://seaotters.com/2012/03/helping-to-save-sea-otters-and-how-they-are-helping-to-save-us/
- http://www.otterproject.org/

MAIN SOURCES

Final Revised Recovery Plan for the Southern Sea Otter (Enhydra Lutris Nereis). Portland, Or.: U.S. Fish and Wildlife Service, Region 1, 2003. Web. 25 Nov. 2016.

U.S. Fish and Wildlife Service. “Southern Sea Otter (Enhydra Lutris Nereis_.” ECOS Environmental Conservation Online System. N.p., n.d. Web. 25 Nov. 2016.
<https://ecos.fws.gov/ecp0/profile/speciesProfile?spcode=A0A7>.

U.S. Fish and Wildlife Service. “Southern Sea Otter.” Ventura Fish & Wildlife Office - US Fish & Wildlife Service. N.p., n.d. Web. 25 Nov. 2016. <https://www.fws.gov/ventura/endangered/species/info/sso.html>.

"12 Ways You can Help Sea Otters" Awesome Ocean. N.P. 22 Sept 2014. Web. 26 Nov. 2016
<http://awesomeocean.com/2014/09/26/12-ways-can-help-sea-otters/>.

IMAGE URLS

In order of appearance:

· https://www.google.com/search?hl=en&site=imghp&tbm=isch&source=hp&biw=1439&bih=713&q=sea+otters+eating&oq=sea+otters+eating&gs_l=img.3..0l5.839.5929.0.6753.26.15.2.8.8.0.274.2337.0j7j5.12.0....0...1ac.1.64.img..6.20.1979.Q75JNJEiiVg#hl=en&tbs=isz:l&tbm=isch&q=male+sea+otter&imgrc=gad1gTfIgCNCzM%3A

· Final Revised Recovery Plan for the Southern Sea Otter (Enhydra Lutris Nereis). Portland, Or.: U.S. Fish and Wildlife Service, Region 1, 2003. Web. 25 Nov. 2016.

· http://latimesblogs.latimes.com/unleashed/2008/07/californias-bel.html

· http://www.biologicaldiversity.org/species/mammals/sea_otter/index.html

· https://www.google.com/search?q=southern+sea+otter+charts&biw=1415&bih=754&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjMuebwk8_QAhUE6IMKHSafAa4Q_AUIBigB#tbm=isch&q=southern+sea+otter+kelp&imgrc=MAU1e_xhcnWKaM%3A

2 comments:

DrWildlifeNovember 29, 2016 at 6:30 PM
Very interesting Juliana! There are a lot of similarities between threats to marine mammals that I've noticed, with oil spills and entanglements really posing a problem. Well done, very well organized and intriguing.

-Nicholas Dockery
DrWildlifeDecember 10, 2016 at 1:09 PM
The layout made the information very clear and organized! Great job with also pointing out links that can direct people to the sites where immediate help can be given.

- Austine De Los Santos

Tuesday, November 29, 2016

Southern Sea Otter - Juliana De La Cruz

SOUTHERN SEA OTTER (Enhydra lutris neresis)