State fisheries workers plan to sample the Elk and Kanawha rivers next week to see if January’s chemical leak affected fish health.
Division of Natural Resources crews will collect redhorse suckers, a bottom-dwelling species of fish, and will send samples of their remains to a federal science center for analysis.
“We’re just doing due diligence,” said Bret Preston, the DNR’s fisheries chief. “We do a certain number of these surveys every year, on waters throughout the state, but we thought that in light of the spill we should do an investigation to see if there are any long-term or short-term fish health problems on the Elk and Kanawha.”
Visual surveys done in January, immediately after as much as 10,000 gallons of the coal-washing chemical MCHM leaked from a holding tank into the Elk, showed no evidence of fish kills or distress.
Subsequent electrofishing surveys showed no apparent effect on fish populations. A June survey of mussel beds downstream from the spill site “found nothing abnormal in terms of presence, absence or difference in numbers” of mussels, Preston said.
The upcoming surveys won’t focus on fish numbers but will examine samples of fish tissue to try to detect if molecular changes are occurring.
Preston said the study will focus on redhorse suckers for two reasons — one, the species is a bottom-feeder and was more likely than free-roaming species to be caught in the bottom-hugging chemical plume; and two, the U.S. Geological Survey’s Leetown Science Center in the Eastern Panhandle has volumes of data about the species.
“During the USGS studies of fish health on the South Branch [of the Potomac River], they’ve learned a great deal about that fish. If there’s something different about the Elk River fish, they’ll be able to see it,” he explained.
“The work they do at Leetown goes all the way down to the cellular level, looking at the fish’s various organs, looking at some really detailed stuff that our staff doesn’t have expertise on.”
The surveys will be conducted by “electrofishing” — shocking the water with a mild direct current that stuns the fish so they can be netted. Nontargeted species will be released immediately, while the targeted redhorse suckers will be killed and have tissue samples removed and prepared by DNR biologists for testing.
Preston said river levels would determine the days when the surveys take place.
“With rains we’ve gotten, might not get them in right away if [river levels] really come up,” he said. “But we’ll certainly have them done sometime soon. Ideally, we’d like to get a couple of collections, especially on the Elk.”
Reach John McCoy at firstname.lastname@example.org or 304-348-1231.