Mercury contamination of small farm ponds and surrounding terrestrial communities may be one of the largest unstudied mercury pollution problems in the United States. Humans have built thousands of small ponds in the south central U.S., mostly as a source of water for livestock, erosion control and recreational fishing. These ponds have become contaminated with atmospherically deposited mercury.

In aquatic ecosystems, less toxic forms of mercury deposited from the atmosphere are converted to highly toxic methylmercury. Methylmercury is incorporated into the aquatic food web and for many years scientists assumed that only aquatic organisms are contaminated with methylmercury. However, recent research has shown that the methylmercury produced in aquatic ecosystems can be transported to terrestrial consumers via insects emerging from small farm ponds.

Click here to find out more information about how pond aging and insect communities affect the mercury transport from farm ponds into terrestrial ecosystems.