Overwhelming international scientific consensus confirms that human activities are disturbing Earth's climate [1,3,4]. Science has demonstrated that atmospheric carbon dioxide (CO2) has increased by 35% (currently ~ 387ppm) and that Earth, as a whole, has warmed about 1.5o F in the past century alone. Effects from climate change are already threatening biodiversity and human health and are expected to increase [1,3,4,6,9].
Polar Bears and the Arctic Habitat
Polar bears are powerful icons for climate disruption impacts. They are arctic inhabitants which require sea ice for their critical habitat. Polar bears rely on winter ice formation to mate and to hunt seals (which have an extremely high fat content) in order to build up their own supply of body fat to sustain them while on land throughout the summer when the ice recedes. The polar bear's ability to meet its fat requirements directly depends on the existence of ice habitat since they cannot survive on the low-fat content of terrestrial mammals or vegetation.
One of the most obvious effects of climate disruption is the accelerated loss of sea ice coverage that has occurred from 1979 to 2012, with unprecedented loss occurring in 2007 and 2008 [5]. Take time to watch this Ice Loss video (provided by Polar Bears International, developed by Ignatius G. Rigor, University of Washington, Seattle Applied Physics Lab) which depicts annual sea ice formation (winter) and recession (summer) over the last 30 years. Take special note of what has happened to the white multi-year ice that should remain relatively stable year-round, the movement of the ice measurement buoys (red dots) as they flow into the Atlantic Ocean, and the amount of overall ice coverage there was in 1979 compared to 2012.
Climate disruption is causing the arctic ice to melt earlier in the spring and freeze later in the fall. Reductions in the amount of time polar bears can spend hunting on sea ice is already affecting polar bear health and productivity. Female body weights are decreasing, the number of independent yearlings are declining, female reproductive intervals are increasing [10], and famished males awaiting the formation of sea-ice are now cannibalizing young polar bear cubs [12].
Beyond the Polar Bear
Thousands of species and habitats are being affected by climate disruption. For example, certain bird species are nesting [11] and migrating earlier. Temperate species, such as the Pika, are moving to higher altitudes [2], amphibian populations are being decimated by infectious diseases [8], and coral reefs are dying [7].
Coral reefs are the most biologically diverse habitats of the oceans and support more than 4,000 species of fish, 800 species of hard corals, and hundreds of other species that serve as an invaluable food supply for millions of people. Coral reefs are also directly affected by increasing levels of CO2 since the gas dissolves in oceans making them too acidic for many species to survive. Coral reef mortality started when atmospheric CO2 exceeded 320ppm and has increased to the current level of ~387ppm.
What Can YOU Do?
YOU have the power to do something meaningful! Immediate mitigation is still possible and vitally needed to reduce carbon emissions and increase carbon uptake. Unfortunately, most people do not believe their personal actions can make a difference but this assumption is an FALSE! Local actions have global effects and the personal actions of individuals can serve to save not only the polar bear and its habitat , but also the species in peril right in your own region. Our Climate Disruption Resource page offers simple ways YOU can make a difference!
What is AZA Doing?
AZA-accredited zoos and aquariums collectively serve over 180 million visitors each year. Many institutions and consortiums already are working actively on climate programs for local and regional audiences. AZA is working on a 5-year Climate Initiative that builds from this work to help our member institutions engage in sustainable practices and deliver a consistent message platform to engage our enormous national audience in understanding and acting to diminish climate impacts on wildlife. Read more about zoo and aquarium sustainable practices.
AZA is also combining resources from it's Conservation Education, Public Relations, Marketing, and Field Conservation Committees, the Green SAG, the Aquariums and Climate Coalition, the Northwest Alliance of Zoos and Aquariums, The Ocean Project, and Polar Bears International to develop and deliver consistent messaging for our enormous audience. Numerous AZA-accredited zoos and aquariums are collaborating on research projects designed to find effective ways to help visitors understand how climate change impacts wildlife well as empower these visitors to make informed choices and personally engage in sustainable practices. Read more about how zoos and aquariums are working collaboratively.
References
[1] ACIA 2004, Impacts of a Warming Arctic: Arctic Climate Impact Assessment Report. Cambridge University Press.
[2] Beever, E.A., Brussard, P.F., Berger, J. (2003). Patterns of apparent extirpation among isolated populations of Pikas (Ochotona, princeps) in the Great Basin. Journal of Mammalogy 84 (1): 37-54.
[3] Global Climate Change Impacts in the United States, 2009. T.R. Karl, J.M. Melillo, and T.C. Peterson (eds.) Cambridge University Press.
[4] Intergovernmental Panel on Climate Change, 2007. Fourth Assessment Report. Climate Change 2007: Synthesis Report (Summary for Policymakers). Available online at http://www.ipcc.ch/ipccreports/ar4-syr.htm.
[5] IUCN Polar Bear Specialist Group Meeting, July, 2009. Greenland Institute of Natural Resources, Copenhagen, Denmark.
[6] Lovejoy, T., L. Hannah (eds). 2005. Climate Change and Biodiversity. New Haven, CT: Yale U.P.
[7] Orr, J.C., K. Caldeira, V. Fabry, J.P. Gattuso, P. Haugan, P. Lehodey, S. Pantoja, H.O. Pörtner, U. Riebesell, T. Trull, M. Hood, E. Urban, W. Broadgate (2009) Research Priorities for Ocean Acidification, report from the Second Symposium on the Ocean in a High-CO2 World, Monaco, October 6-9, 2008, convened by SCOR, UNESCO-IOC, IAEA, and IGBP, 25 pp.
[8] Pounds, J.A. et al. 2006. Widespread amphibian extinctions from epidemic disease driven by global warming. Nature 439: 161-167.
[9] Root, T.L., S.H. Schneider. 2002. Climate Change: Overview and Implications for Wildlife. From S.H. Schneider and T.L. Root (eds). 2002. Wildlife Responses to Climate Change: North American Case Studies. Washington, D.C.: Island Press.
[10] Stirling, I., Lunn, N. J., Iacozza, J. 1999. Long-term trends in the population ecology of polar bears in western Hudson Bay in relation to climatic change. Arctic, 52, 294-306.
[11] Torti, V.M., P.O.Dunn. 2005. Variable effects of climate change on six species of North American birds. Oecologia 145: 486–495. Melting Habitat. 2004. Environment 46(4): 5-6.
[12] PBI staff observations during November 2009.