USGS Study: Mountaintop Removal Mining Impacts Fish Populations

Jul 9, 2014

Mountaintop removal mining does have an effect on fish populations downstream from the mining operations, according to a study just released by the U.S. Geological Survey.

The study title is a mouthful: Temporal changes in taxonomic and functional diversity of fish assemblages downstream from mountaintop mining, which is the fancy way of saying USGS scientists looked at how well fish populations are doing in streams down river from mountaintop mining sites.

The co-authors are Doug Chambers, a biologist and water quality specialist in Charleston, West Virginia, and Than Hitt, a fish researcher at the Leetown Science Center in Jefferson County, West Virginia.

The study looked at changes with respect to:

  • The number of species found in streams below mountaintop removal sites
  • The number of fish
  • How the fish behave
  • Their feeding traits and the strategies they use to survive
  • Physical habitat and water quality

“And by looking at how those things change over time we can get some clues about what’s really happening in the system,” Hitt said.

This creek chub (Semotilus atromaculatus) collected by Than Hitt and Doug Chambers downstream from MTM operations shows classic signs of selenium toxicity (spinal abnormality).
Credit Submitted Photo / U.S. Geological Survey

Over a two year period of time, in 2010 and 2011, Chambers and Hitt collected samples from the Guyandotte River Basin in southern West Virginia. Streams that were studied include the Upper Mudd River, the Left Fork of the Mudd, Big Ugly Creek and Laurel Creek. All these streams are down river from mining sites. They were able to compare their samples to data collected in 1999 and 2001 for a water quality study done by Penn State University researchers.

Some study results:

  • The streams in the study contain 25 species that are generally found in an Appalachian stream, including creek chub, minnows, sunfish and darters. 
  • There were fewer fish downstream from the mining sites and half the number of species.
  • A minority of species can do quite well in the conditions created by mine runoff including the creek chub and green sunfish.
  • Mountaintop mining creates many changes to the landscape, including the way water flows.
  • The process of breaking big rocks into smaller ones releases more minerals and chemicals so the water below valley fills contains higher concentrations of selenium
  • Selenium is an essential, non-toxic nutrient that can be harmful when too much is consumed because it reduces the fish’s ability to reproduce.
  • How well the fish survive changes in water quality depends on what they eat and fish with more diverse diets do better.

And Chambers said the results can help policy makers as they decide how to regulate the state’s water resources.

“West Virginia right now is blessed with abundant water," he said. “If we’re going to continue to have readily available abundant water we need to understand the processes that affect its quality very broadly.”

Both scientists said the study also provides a framework for future research- both in the field and in a lab setting.