Wednesday, March 15, 2017

The Chesapeake Bay - Part 3

I love the Chesapeake Bay - it seems that it's always there, in my memories...  I've been swimming in the Bay, I've fished and crabbed, clammed and oystered in it.  I've been boating on it.  Unless there's a big storm, it's very calm, compared to the ocean; but when it's windy, the chop, can just about kill you.  People get lost in it, people die in it.  It's just a smaller ocean that they're on....
    In the 1970s, while I was in high school, it was discovered that the Chesapeake Bay contained one of  Earth's first identified marine dead zones.  The waters were so depleted of oxygen that they were unable to support life, which led to massive fish kills.  It's estimated that, even today, the dead zones in the Bay kill up to 75,000 tons of clams and worms, which live on the bottom of the Bay, which weakens the base of the estuary's food chain, and robs the blue crab, in particular, of a primary food source.  Crabs are occasionally seen massing on the shore to escape pockets of  oxygen-depleted water, a behavior called a "crab jubilee."  The hypoxia, or oxygen depletion, results in part from large blooms of algae, which are nourished by the runoff waters of residential, farm, and industrial waste throughout all the contributing watersheds.  One report in 2010 criticized Amish farmers for having cows that "generate heaps of manure that easily washes into streams and creeks, and flows onward into the Chesapeake Bay."  But farmers should not be singled out... everyone east of the eastern mountains contributes to the pollution of the Bay waters.
    The runoff and pollution have many components that help contribute to the algae bloom, which is mainly fed by phosphorus and nitrogen.  The algae prevents sunlight from reaching the bottom of the Bay while it's alive, and it de-oxygenates the Bay's water when it dies and rots. Another blocking of sunlight is caused by erosion and the runoff of sediments into the Bay, which, in turn, is caused by devegetation, construction, and the prevalence of pavement in urban and suburban areas.  The resulting loss of aquatic vegetation has reduced the habitat for much of the Bay's aquatic life.  Beds of eelgrass, the dominant variety in the southern portion of the Bay, have shrunk by more than half in the last 40 years.  Over-harvesting of fish and shellfish, pollution, sedimentation, and disease have turned much of the Chesapeake's bottom into a muddy wasteland.
    One particularly harmful source of toxicity is Pfiesteria piscicida, which affects both fish and humans.  Pfiesteria caused a small regional panic in the late 1990s; a series of large blooms started killing large numbers of fish, and people who swam in the water developed mysterious rashes.  Eventually, nutrient runoff from chicken farms was blamed for the algae growth, fish deaths, and human rashes.
   Thanks to multiple state and national programs, the Chesapeake Bay improved slightly in terms of the overall health of its ecosytem in 2010.  In 2008, it earned a rating of 28, out of 100; in 2010, it had a rating of 31.  An estimate in 2006 from a "blue ribbon panel" of of watermen, ecologists, and scientists stated that the cleanup costs for the Bay would be about $15 billion - and that would be to get the Bay's rating up to only 70 of 100 points.  One of the problems that compounds the difficulty of the Bay's recovery is that 100,000 new residents move to the Chesapeake Bay shore area each year.  A report in 2008 in The Washington Post suggested that government administrators had overstated the progress of cleanup efforts to "preserve the flow of  federal and state monies to the project."  In January 2011, there were reports that millions of fish had died in the Bay; instead of an investigation, however, officials suggested that the kill was the result of extremely cold weather.
    The latest report on the overall health of the Chesapeake Bay, in 2015, gave a total rating of 53 out of 100.  In 2013, it had a rating of 45.  With work and funding, we might be able to bring the Bay back to what it used to be....

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