Adirondack dragonflies tested for mercury contamination in mountain waters
Wednesday, October 17, 2012 - 2:21 pm

Adirondack dragonflies are being tested for mercury contamination in mountain waters.

The Adirondack Lakes Survey Corporation recently completed collections of dragonfly larvae in acid-rain sensitive waters.

The concept of using dragonfly larvae as bio-sentinels for mercury concentrations in Northeast lakes and streams is being developed by the University of Maine Mitchell Center & School of Forest Resources, with the SERC Institute, Maine Sea Grant, the USGS Mercury Research Lab, and Dartmouth College.

The idea is that waters affected by acid rain could be picking up mercury from the same emissions from powerplants and metals smelters thta are causing acid rain effects.

Dragonfly larvae -- immature dragonflies -- live in the water for the first year or years of their lives.

The project will study dragonfly larvae mercury and lake water mercury in a statistical set of lakes across New York and the New England states.

“Our work has been using dragonfly larvae as bio-sentinels, to help us understand which types of watersheds and waterbodies seem to have greater mercury,” said University of Maine’s Dr. Sarah Nelson. “The work will help us understand if we can model mercury sensitivity in lakes and their food webs, and if dragonfly larvae are good indicators of that sensitivity.”

Mercury is a natural element but is found in elevated levels in Maine and many locations across the country due largely to fossil fuel emissions. Mercury travels far in the atmosphere and often lands in environments distant from where it is emitted including remote locations worldwide.

Scientists are unable to predict which lakes or streams might have high or low mercury because it has a complex cycle both getting to waterbodies and once it’s in the water.

The data collected and analyzed by the ALSC has and continues to be utilized as one of the major sources for the development of state and federal policies on emission control and air transport regulations. Sampling, chemistry analysis, and data products include water, fish, snow, and cloud collections on acid deposition research projects.

More info: Dr. Nelson, (207) 581-3454, Sarah_Nelson@umit.maine.edu.