You Otter Think About Saving the Northern Sea Otters

You Otter Think About Saving the Northern Sea Otters 

Amanda Ahearn

Source: http://www.flickr.com/photos/marlinharms/7370629006/

The words “sea otter” usually come with a positive connotation. People are led to talk about how cute they think sea otters are or maybe how they have never seen one in person but really want to. Rarely does the topic of species endangerment come up. Previous to this class, I myself had no knowledge that the sea otter was an endangered species. For this specific post, I will be focusing my efforts on the recovery plan for the Northern Sea Otter located in Southwest Alaska. 

   

Description and Ecology

Sea otters are the largest mustelid with males measuring up to 45 kg and females measuring up to 36 kg. Sizes vary among different population and may correlate with the amount of food available to said population. The taxonomy of the sea otter is based on the morphology of its skull. The sea otter is in the order Carnivora. There are two sea otter lineages as well: Enphydriodon and Enphydritherium. 

Geographic and Population Changes

Management Units. Source: http://ecos.fws.gov/docs/recovery_plan/Recovery%20Plan%20SW%20AK%20DPS%20Sea%20Otter%20Aug13.pdf

The Northern Sea Otter occurs only in the North Pacific Ocean, however, it does have a historical geographic range. They used to be located around the Pacific Rim between Central Baja California and Northern Japan. The animal uses most of the coastal marine habitats that are found in its specific range. This includes bays, estuaries and offshore islands. They can also be found in waters a few kilometers off shore. They tend to forage in bottom types such as fine mud and sand. Researchers have found a positive correlation between shoreline complexity and sea otter density.

Very little is known about the long-term patterns of sea otter abundance. It is suggested, however, that indigenous people of the North Pacific made use of the sea otter, which could have had a direct influence on the abundance. The abundance of sea otters was pretty stable until the beginning of the 20^th century when the population was reduced to a few thousand individuals. They were then reintroduced in the 1960s and 1970s in southeast Alaska, British Columbia, Washington and Oregon. In 1989, there was a dramatic decline of sea otters in Aleutian Archipelago due to an Exxon Vladez oil spill. The effects lasted well into the 1990s. Since the 1990s, the sea otter population has grown 2-3% per year; slow and steady wins the race. The most significant declines in sea otter populations occurred in the 1990s and from 2007-2009.

 

Listing Date and Type of Listing

The Northern Sea Otter was listed on the Endangered Species List on August 9, 2005 as a threatened species. 

 

Source:http://wildwhales.org/killer-whale/

Main Threats/Cause of Listing
 

The species has many threats that could be a detriment to the population. One of the major threats is that of predation. Some of the species that threaten sea otters are bald eagles, white sharks, terrestrial carnivores and killer whales. Other less threatening but still important threats include infectious disease, biotoxins, contaminants, oil spills, food limitation, bycatch/entanglement, subsistence harvest, habitat concerns and  illegal take.  All of these elements pose a threat to the sea otter, which is a main reason, why a recovery plan was created. 

http://www.treehugger.com/natural-sciences/it-took-25-years-sea-otters-get-over-exxon-valdez-oil-spill.html

Recovery Plan

The goal of the recovery plan created is to control, reduce or eliminate threats that could harm the survival of the sea otter population. There are three main objectives to the recovery plan. They are: to achieve a self-sustaining sea otter population, maintain enough sea otters so that they can have a useful role in their ecosystem ad to alleviate threats. In order to go forward with this plan, researchers must monitor the population, understand habitat needs, manage human impacts, evaluate the roles of disease and predation, and to, finally, implement the plan entirely. Hopefully after all of this, the sea otter population will thrive!

           

  Sources: 

All information from the Recovery Plan: 

http://ecos.fws.gov/docs/recovery_plan/Recovery%20Plan%20SW%20AK%20DPS%20Sea%20Otter%20Aug13.pdf