PERRYVILLE, Missouri — Water quality, not the number of fish, will be the biggest factor determining what happens in the effort to save an endangered fish found only in a small area of southeast Missouri.
In September, the U.S. Fish and Wildlife Service added the grotto sculpin to the list of endangered species but decided against designating a "critical habitat," which local officials feared could have caused restrictions harming economic development.
The cave-dwelling grotto sculpin is a tiny fish with a pale skin color with reduced, and sometimes absent, eyes. It is found only in Perry County, about 75 miles south of St. Louis.
The Southeast Missourian (http://bit.ly/1cHMIN7 ) reports that the Fish and Wildlife Service will review data in five years.
"We're going to base recovery on water-quality parameters. ... Counting fish can be tricky," Fish and Wildlife Service biologist Shauna Marquardt said at a public meeting Wednesday.
That doesn't mean the population won't be watched — the Missouri Department of Conservation will try to keep count. But baseline data are limited, and "we can't always count those fish with 100 percent confidence," Marquardt said.
Water quality, though, can be tested more frequently, and monitoring will show how the conservation plan is working, Marquardt said.
At times, Perry County's water quality has fallen below the standards necessary to maintain aquatic life. The result has been occasional "fish kills" that raise concern about survival of the grotto sculpin, Marquardt said.
"The plan is not really going to be about the fish," said Frank Wideman of the University of Missouri Extension. "The fish is going to be an indicator to ... help us figure out if we're making the right kind of improvements or not."
Wideman said the county's geology includes sinkholes that allow surface water — often containing sediments with sewage, chemicals and other contaminants — to run into the caves, compromising groundwater quality and endangering the fish.
"If we keep the soil out of the caves, we've got a major part of the problem fixed," he said.
Doing that will require the use of buffer zones, no-till farming techniques, cover crops and other efforts by landowners to keep water clean, Wideman said.
Had Perry County been designated as critical habitat for the grotto sculpin, those measures would have been mandatory.
Information from: Southeast Missourian, http://www.semissourian.com