While surveying fishes in Georgia’s Flint River, Byron and Mary Freeman noticed that a certain darter fish had a striking orange color in its fins—much different than the Blackbanded darter that is prominent in the southwest Georgia River. The University of Georgia researchers had indeed come across a new species: the Halloween darter or Percina crypta.
“The Halloween darter is a great example of ‘cryptic biodiversity’—species that have gone unrecognized because they look a lot like other species that are known,” explained Mary, an ecologist with the U.S. Geological Survey and the UGA Odum School of Ecology. “Ichthyologists have documented many new fish species in the southeastern U.S., showing that despite nearly 100 years of scientific study of fishes in this region, there are still surprises.”
The newly discovered Halloween darter is less than five inches long and upon analysis, was found to have a host of differences from the Blackbanded darter. The fish is common to only a few areas of the Chattahoochee and Flint River systems because it requires habitats with swift water currents over rocky areas—shoals. Findings were reported in a recent issue of prominent zoological journal Zootaxa.
According to Mary, there are far fewer shoals today because of the rise of dams on rivers and streams, as well as the removal of rock shoals to improve rivers for navigation. The discovery of the Halloween darter has definite implications for conservation strategies.
“Keeping track of the status of the Halloween darter, along with other species that require shoal habitats in the Chattahoochee and Flint Rivers, will provide information on how shoals as ecological systems are responding to changes in land use, water management and climate,” said Mary.
In addition to the Freemans, the research team included Noel Burkhead of the U.S. Geological Survey and Carrie Straight, a Ph.D. student at the UGA Odum School of Ecology.