Super-sized crabs may be the next side effect of climate change, according to scientists at the University of North Carolina’s Aquarium Research Center. Researchers analyzed Chesapeake Bay blue crabs kept in both high-carbon and low-carbon tanks. Crabs in the high-carbon tanks grew at almost four times the rate of the other crabs.
Fossil fuels are tied to rising carbon dioxide in our oceans. As a result, creatures like crabs, lobsters, and shrimp are growing larger, faster. While this might sound like good news for seafood lovers, bigger crabs tend bulk up on their shells, not their meat. Plus, bigger crabs have bigger appetites, which is bad news for prey like oysters.
And it’s not only crabs that are posing a threat to oysters. Oceans are absorbing 22 million tons of carbon dioxide every day. As oceans absorb more carbon dioxide, they become more acidic. Oysters rely on a delicate pH balance to build and maintain their calcium carbonate shells. And this balance is being thrown out of whack by the ocean’s changing chemistry.
The precarious position of oysters is bad news for the health of our waterways. According to the EPA, more than half of all rivers and streams in the U.S. are in poor condition due to pollution. And oysters play a key role in the health of coastal ecosystems. They act as natural water filters, absorbing pollution and pumping out clean water. They also create reefs that provide shelter for small fish, crabs, and plants.
If oysters become fewer and weaker, we lose more than an appetizer – we lose a key resource in fighting water pollution.
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Web Links
http://www.emagazine.com/blog/where-have-all-the-oysters-gone1
Oysters Help Filter Pollution in New York Rivers
http://www.realscience.us/2012/08/28/oysters-help-filter-pollution-in-new-york-rivers/
Oysters Threatened by Ocean Acidification
http://www.care2.com/greenliving/oysters-on-the-thin-shell.html
Photo, taken on November 28, 2010, courtesy of Jules Morgan via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio. Support for Earth Wise comes from the Cary Institute of Ecosystem Studies in Millbrook, NY.