WASHINGTON (CN) – The brightly colored candy darter, a small Virginia fish threatened by interbreeding, has prompted a federal agency to ask for anglers’ help. In a press release announcing the U.S. Fish and Wildlife Service’s decision to propose the darter for listing under the Endangered Species Act the agency made the unusual request due to what is known as “bait bucket transfer,” caused by fishermen inadvertently transferring one species, perhaps as unused live bait, into the habitat of another species.
In this case, the introduction of the variegate darter into candy darter habitat has complicated the candy darter’s chances for survival, because the two closely related species interbreed.
“Passing wildlife laws alone cannot protect our native fauna,” Dan Cincotta of the West Virginia Division of Natural Resources said. “It is imperative to inform the public, especially anglers, about the negative impacts associated with moving species into new environments.”
The candy darter has been a species of concern for decades. The USFWS listed the fish as a candidate species in 1982, though no action was taken. In 2010, the candy darter was included in a petition from the Center for Biological Diversity (CBD) to list 404 aquatic species in the southeastern United States under the ESA. The USFWS responded to that petition in 2011, finding that 374 of those species, including the candy darter, merited further review.
However, due to continued inaction, the CBD sued the USFWS in 2015, which resulted in a settlement agreement stipulating that the service would make a finding on the candy darter by Sept. 30, 2017.
Another darter included in the settlement agreement has also advanced toward ESA listing. The trispot darter found in Alabama, Georgia and Tennessee was also proposed for listing in a separate action in which the USFWS declined to list two other darters, the holiday darter and bridled darter, maintaining that after further scientific review, listing for those two species was not needed.
“The Trump administration is such an enemy to the environment that we’re surprised and elated to see even two of these imperiled fish move closer to protection,” Tierra Curry, a senior CBD scientist said. “The decision not to propose protection for the holiday darter and the bridled darter sure smells fishy, though, so we’ll carefully review the best available science and consider challenging those determinations in court.”
The bridled darter is only found in six surviving populations, all in poor condition, and the holiday darter are only known in seven populations, six of which are also ranked as being in poor condition, the CBD said.
Darters are small fish that live mainly in clear streams and river basins. Water quality is threatened by storm water runoff from development and agriculture, and from habitat degradation caused by logging, mining, dams, pollution and drought.
The candy darter only survives in half its historic range and the trispot has lost 80 percent of its range. “The condition of the trispot darter is an indicator that habitat conditions, stream flows and water quality are declining in the Coosa River Basin,” Mike Oetker, the service’s acting regional director in the Southeast said. “The good news is that we believe we can reverse those declines and recover the trispot through ESA-inspired efforts, and working with our partners in Georgia, Alabama, and Tennessee to build on some good conservation work already underway.”
Both the candy and the trispot have been proposed for threatened listing status under the ESA. Unlike an endangered status, which signals an imminent extinction risk, a threatened status means that the extinction risk is high in the foreseeable future. In the case of the candy darter, the USFWS estimates that hybridization will cause the fish to be in danger of extinction within 20 years. The service also used the 20 year time frame for the trispot determination.
The USFWS said it would propose critical habitat for the candy darter within one year, but said critical habitat for the trispot is not determinable at this time.
“The Endangered Species Act has prevented the extinction of 99 percent of the plants and animals under its care, and its protection is the best lifeline to prevent more imperiled species from being lost forever,” CBD’s Curry said.
Comments on the two proposed listings are due within 60 days of the Oct. 4 publication date.