Is there any place that's not polluted?

Photo by Jim Lo Scalzo /EPA 

A Great Blue Heron walks near the banks of the Anacostia River in the Kenilworth Park & Aquatic Gardens in Washington, D.C., U.S.A.   The river is routinely listed, by environmental groups, as one of the most polluted waterways in America.   While there are many species of creatures and plants living here, there are also many invasive species of concern in addition to the pollution.   One of the invasive species is the Snakehead fish...a new one for me...you may want to Google it.

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BtheB