The seal hunts are not the only problem that harp seals face. Global warming is also a huge threat to these seals. Global warming, caused by an increase in green house gases in our environment mostly due to human consumption, has been gradually increasing the earth's atmospheric and oceanic temperatures since the early 1900s.
Harp seals breed and give birth on ice sheets in the Northern Atlantic, centralized in the Saint Lawrence bay in Canada. The pups are then reared on the ice before they learn how to swim and become independent enough to be on their own.
Ice stranding among harp seals versus ice cover in the Arctic
Johnston et al.
Johnston et al.
The increase in earth's temperature has drastically reduced the amount of ice available in the ocean for these mating and birthing rituals. Seals are forced to choose thinner or smaller chunks of ice, which, according to the graph above, increases the incidence of stranding among harp seal pups. Stranding occurs when a pup is either separated from its mother or introduced to the water to early for survival. Increased stranding rates further reduce the seal population among pups.
Resources
Deal, Clara, Sang H. Lee, Scott Elliott, Elizabeth Hunke, Mathew Maltrud, Nicole Jeffrey, and Meibing Jin. "Investigation of Arctic Sea Ice and Ocean Primary Production for the Period 1992–2007 Using a 3-D Global Ice–ocean Ecosystem Model." CHINAREs 81 (2012): 28-35. Web.
Deal, Clara, Sang H. Lee, Scott Elliott, Elizabeth Hunke, Mathew Maltrud, Nicole Jeffrey, and Meibing Jin. "Investigation of Arctic Sea Ice and Ocean Primary Production for the Period 1992–2007 Using a 3-D Global Ice–ocean Ecosystem Model." CHINAREs 81 (2012): 28-35. Web.
Harkonen, Tero, Karin C. Harding, Lilia Dimetrieva, Susan Wilson, Carl J. Svensson, Simon J. Goodman, and Mirgaliy Baumukanov. "Collapse of a Marine Mammal Species Driven by Human Impacts." PlosOne 7.9 (2012): n. pag. Web.
Johnston, David W., Matthew T. Bowers, Ari S. Friedlaender, and David M. Lavigne. "The Effects of Climate Change on Harp Seals." PlosOne 7.1 (2012): 1-8. Web.
Mosher, Dave. "Baby Harp Seals Being Drowned, Crushed Amid Melting Ice." National Geographic. National Geographic Society, 06 Jan. 2012. Web. 25 Feb. 2013. <http://news.nationalgeographic.com/news/2012/01/120106-harp-seals-global-warming-sea-ice-science-environment/>.
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