Polar:Penguins: Endangered by Melting Ice
Emperor penguins at Snow Hill Island, Antarctica. Credit: http://www.flickr.com/photos/marthaenpiet/ / CC BY-NC-ND 2.0
Published: December 16, 2010, 12:00 am
Updated: May 7, 2012, 6:46 pm
This article has been reviewed by the following Topic Editor:
David Hassenzahl PhD
Rising temperatures and loss of snowpack or ice caps endangers a number of alpine and arctic species, including penguins. At the Antarctic, several species of penguins that depend on sea ice are experiencing population changes [1]; Colonies of Adélie penguins are declining at warmer sites, such as Anvers and King George Island, but expanding at colder sites such as Cape Royds on the Ross Sea. This indicates that populations of Adélie penguin are shifting location. [2] Emperor penguins also depend on sea ice, and their colony at Point Geologie is declining.
Both Adélie penguins and emperor penguins nest near Point Geologie, but at different times of the year. Temperatures at this site have remained relatively constant over the past 50 years, while the extent of sea ice has diminished 66%. [3] The date of the penguins’ arrival at the site has remained relatively constant for the two species, whereas the date on which they begin laying eggs is now delayed by a few days. Apparently, the decreased amount of sea ice has reduced the quantity and accessibility of food supplies such as krill, and these penguins need more time to build up the fat reserves necessary for breeding. [3]
Penguins in Antarctica (A) Locations of Adélie and emperor penguin colonies on Antarctica for which multiyear censuses of population size are available. (B) Number of breeding pairs of Adélie penguins on Anvers Island and King George Island are declining, whereas the colony on Signy Island is highly variable in size, and that on Cape Royds is growing. The colony of emperor penguins on Point Geologie is shrinking. [B after Croxall et al. 2002.]
This is an excerpt from the book Global Climate Change: Convergence of Disciplines by Dr. Arnold J. Bloom and taken from UCVerse of the University of California.
©2010 Sinauer Associates and UC Regents
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Citation
Arnold J Bloom (Lead Author);David Hassenzahl PhD (Topic Editor) "Penguins: Endangered by Melting Ice". In: Encyclopedia of Earth. Eds. Cutler J. Cleveland (Washington, D.C.: Environmental Information Coalition, National Council for Science and the Environment). [First published in the Encyclopedia of Earth December 16, 2010; Last revised Date May 7, 2012; Retrieved June 19, 2013 <http://www.eoearth.org/article/Penguins:_Endangered_by_Melting_Ice?topic=60593>
The Author
Arnold J. Bloom became a botanist through a circuitous route. Upon receiving an undergraduate degree in Physics from Yale University, he spent several years developing computer models of the spread of air pollution over cities in the USA and Germany. He received a Ph.D. in Biological Sciences from Stanford University, where he also completed a two-semester course in Environmental Legislation at the Law School. He conducted postdoctoral research on the temperature responses of plants at the ... (Full Bio)
Rising temperatures and loss of snowpack or ice caps endangers a number of alpine and arctic species, including penguins. At the Antarctic, several species of penguins that depend on sea ice are experiencing population changes [1]; Colonies of Adélie penguins are declining at warmer sites, such as Anvers and King George Island, but expanding at colder sites such as Cape Royds on the Ross Sea. This indicates that populations of Adélie penguin are shifting location. [2] Emperor penguins also depend on sea ice, and their colony at Point Geologie is declining.
Both Adélie penguins and emperor penguins nest near Point Geologie, but at different times of the year. Temperatures at this site have remained relatively constant over the past 50 years, while the extent of sea ice has diminished 66%. [3] The date of the penguins’ arrival at the site has remained relatively constant for the two species, whereas the date on which they begin laying eggs is now delayed by a few days. Apparently, the decreased amount of sea ice has reduced the quantity and accessibility of food supplies such as krill, and these penguins need more time to build up the fat reserves necessary for breeding. [3]
Penguins in Antarctica (A) Locations of Adélie and emperor penguin colonies on Antarctica for which multiyear censuses of population size are available. (B) Number of breeding pairs of Adélie penguins on Anvers Island and King George Island are declining, whereas the colony on Signy Island is highly variable in size, and that on Cape Royds is growing. The colony of emperor penguins on Point Geologie is shrinking. [B after Croxall et al. 2002.]
This is an excerpt from the book Global Climate Change: Convergence of Disciplines by Dr. Arnold J. Bloom and taken from UCVerse of the University of California.
©2010 Sinauer Associates and UC Regents
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