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USGS · 70193201

The desperate dozen: Fishes on the brink

Abstract

IT IS NO SECRET THAT OUR NATIVE AQUATIC ANIMALS ARE IN DECLINE. There are currently 582 species of animals on the Federal list of endangered and threatened species, 268 of these (46%) are found in freshwater habitats. Of the amazing assemblage of 675 fishes found in southeastern waters, more than a quarter are considered imperiled. While all of the Earth’s ecosystems are in trouble, freshwater habitats are recognized to be at severe risk because of their scarcity and the high demands placed on them by humans. The combined effects of agriculture, damming, dredging, construction, logging, overharvest, and pollution are destroying this critical resource for animals, plants, and even ourselves. This major conservation crisis calls for immediate action to conserve and protect the remaining populations and their habitats. The Southeastern Fishes Council (SFC), a nonprofit scientific organization dedicated to the study and conservation of freshwater and coastal fishes of the southeastern United States, is one of the many organizations attempting to reverse the decline of our southeast aquatic habitats and their rich biodiversity. One of the most important steps in conservation is prioritization. The SFC sought to determine where conservation actions would have the largest impact on preventing loss of our freshwater diversity. We decided to focus our efforts on the Desperate Dozen, the 12 fish species we identified as most likely to become extinct in the Southeast. We chose this list in order to reverse their precipitous decline and assist in putting them on the path to recovery. These twelve species are not currently economically important to humans, and their extinction could easily go unnoticed by all but conservation biologists and ichthyologists. Even so, their conservation matters. These species are the canaries in the coal mine, alerting us to the problem that something is very, very wrong in our backyards. Fishes that were once widespread in larger rivers, such as the diamond darter, are now suffering from the same water quality issues that cause harm to humans. Fishes that were once used for commercial gain, such as the Alabama sturgeon, are now too rare for harvest. We have ignored our freshwater to the point where we no longer remember that rivers used to be more common than reservoirs in the Southeast, and our diversity was a resource worth protecting. It is SFC’s goal to use this list to raise awareness of the plight of our freshwater habitats in the Southeast, which include rivers, creeks, wetlands, springs, and caves. The current crisis requires education, communication, and coordination among our neighbors. We have to learn how to prevent harm to our watersheds and develop new collaborations between private and public entities to promote wise development. By highlighting these twelve species, ranging from the spring pygmy sunfish to the Alabama sturgeon, we hope to encourage these partnerships to address the needs of our freshwater animals and hopefully prevent them from slipping quietly into extinction. SFC created a list of the most imperiled southeastern fishes by considering species with the highest risk of extinction. Criteria used, in order of importance, was distribution (a single population ranked highest), low abundance, and severity of threats. After the ranking based on level of imperilment, species were arranged in phylogenetic order so that all would receive equal attention. Experts on each species provided brief accounts on the Desperate Dozen, which include background, distribution, abundance, threats, and proposed conservation actions. The U.S. Fish and Wildlife Service (USFWS) was not consulted in SFC’s identification of the Desperate Dozen fishes, as we intentionally chose to work as an independent scientific panel under the criteria stated above.

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Stuart A. Welsh. 2008. The desperate dozen: Fishes on the brink. https://pubs.usgs.gov/publication/70193201

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Factors affecting benthic macroinvertebrate health in the City of Roanoke, Virginia, 2020–2023

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