Gray Whales Offered as Sentinels of Climate Change

Species dependent on sea ice, such as the gray whale, provide the clearest examples of sensitivity to climate change, according to an article in the June 2008 Journal of Mammalogy, published by the American Society of Mammalogists.

The behavioral ecology of gray whales in the eastern North Pacific and Arctic oceans could help illustrate the importance of ecological processes acting over large spatial scales.

"Much more can be achieved by selecting specific marine mammal species as vectors to investigations of full ecosystems," writes Sue E. Moore in her article "Marine Mammals as Ecosystem Sentinels."

Moore outlines six correlations betweens changes in the distribution and behavior of gray whales and changes in their environment, including the timing of migration and their response to El Niño or La Niña weather patterns. This suggests gray whales are effective sentinels of change in ecosystems, Moore says.

The use of gray whales as sentinels goes beyond tracking distribution changes, Moore says. Tests on the whales' blubber can detect pollutant levels and changes in their diet.

"The overall health of marine mammals ultimately reflects the health of the ecosystems upon which they depend," she writes.

Existing research strategies must be expanded to allow for the use of marine mammals as sentinels of ecosystem change, Moore says. They are ideal for such research because these "charismatic megafauna" capture the public's attention too, she says, providing opportunities for education and outreach on oceanic and environmental issues.

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