Friday, December 2, 2016

Polar Bear - Amy Solari


Polar Bear (Ursus Maritimes)

They can't bear it anymore!
Amy Solari



Description & Ecology

Polar bears are the largest land carnivores in the world. They are apex predators because they sit at the top of the food chain in the biologically rich Arctic. Polar bears are marine mammals and spend much of their time on Arctic sea ice. Many adaptations make polar bears uniquely suited to life in icy habitats. Their fur is very thick and covers their feet for warmth and traction on the ice. Their front feet are large, flat and oar-like, making them excellent swimmers. A thick layer of blubber beneath their fur provides buoyancy to swim and insulation. Although they appear white in color, polar bears fur is actually clear and their skin is black. The average polar bear is between six and nine feet long ranging from 800 to 1,300 pounds. Being the   most carnivorous of the bear species, polar bears feed primarily on ringed and bearded seals because of the large amounts of fat needed to survive. The remains of these seals provide food for many other Arctic wildlife species, giving polar bears a crucial role in their ecosystem. They are also known to eat walruses, beluga and bowhead whale carcasses, birds’ eggs as well as vegetation on rare occasions. The Polar Bear is a K-selected species, meaning late sexual maturity, small litter size, high maternal investment and high adult survival. Their reproductive rate is among the lowest in all mammals, usually giving birth to only two or three cubs. Females generally mature at four to five years and their average life span ranges from nine to thirteen years.

Geographic & Population Changes

Polar bears are quickly becoming an increasing concern. The total polar bear population is divided into nineteen subpopulations. Three of those subpopulations are in decline and there is a high estimated risk of future decline of the other subpopulations due to climate change. In 1973 there were around 31,000 polar bears in the United States. As of 2008, there are between 20,000 and 25,000 polar bears in the US and that number is continuously dropping today. This is because polar bears spend over 50% of their time hunting for food, but less than 2% of their hunts are actually successful, causing many to starve. By 2050 polar bear numbers are predicted to drop by 30%. Due to global warming, ice caps are melting at alarming rates, making it harder for polar bears to find and hunt for seals which results in cannibalistic behavior.
http://wwf.panda.org/_core/general.cfc?method=getOriginalImage&uImgID=%26%2AR%2C%2D%20NW0%0A














Listing Date & Type of Listing

Listing date: May 2008

This map shows the average decline of sea ice from 1979 to 2013.
http://nsidc.org/arcticseaicenews/files/2013/03/Figure3.png    

Type of Listing: Threatened - because of ongoing loss of their sea ice habitat resulting from climate change.


Main Threats to Continued Existence
  • Increased human contact
  • Malnutrition
  • Further decrease in ice caps
  • More habitat fragmentation as a result of climate change
  • Oil and gas spills - as Arctic ice melts, polar bears are affected by increased shipping activities
  • Unreported/illegal hunting in areas where the subpopulation status is declining
http://www.dailymail.co.uk/travel/travel_news/article-2874277/Polar-bear-cub-waves-tourists-Arctic-National-Wildlife-Refuge-Kaktovik-Alaska.html
Recovery Plan
  1. Limit global atmospheric levels of greenhouse gases to levels appropriate for supporting polar bear recovery and conservation, primarily by reducing greenhouse gas emissions.
  2. Support international conservation efforts through the Range States relationships.
  3. Manage human-bear conflicts.
  4. Collaboratively manage subsistence harvest.
  5. Protect denning habitat.
  6. Minimize risks of contamination from spills.
  7. Conduct strategic monitoring and research.
However, to enforce and maintain this recovery plan, it would cost roughly $671,000 annually.

http://www.iucnredlist.org/details/22823/0
What can you do?

Saving polar bears starts with us. 
We should:
  • Drive less/carpool to reduce greenhouse gas emissions
  • Conserve water by ensuring all faucets are not leaky
  • Recycle and keep trash out of the oceans
  • Eat less meat
  • Use less energy overall


Other Resources

IUCN Red List. "IUCN Red List of Threatened Species." Ursus Maritimus (Polar Bear). IUCN, 

Kruger, Elisabeth. "Polar Bear." WWF. World Wildlife Fund, n.d. Web. 1 Dec. 2016. 

"Polar Bear Draft Conservation Management Plan." U.S. Fish and Wildlife Service, 25 June 2013.
   
U.S. Fish and Wildlife Service. "Recovery Plans Search." Endangered Species | Species | Recovery
        Plans Search. N.p., n.d. Web. 1 Dec. 2016. <https://www.fws.gov/endangered/species/recovery-plans.html>.

3 comments:

  1. I had no idea that the problem of malnutrition was so bad that polar bears were resorting to cannibalistic behavior. I wonder if it's possible that they will adapt to hunting for species in warmer habitats as they are pushed further south.
    -Theresa Stewart

    ReplyDelete
  2. I thought I knew a lot about the polar bear, but this taught me so much new information!
    Bailey Runnells

    ReplyDelete
  3. Great choice of species! polar bear can act as umbrella species for lots of other issues such as global warming! the flow of the blog was really good as well.
    - Javier Suarez

    ReplyDelete