Scaleshell Mussel Leptodea Leptodon
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U.S. Fish & Wildlife Service Endangered Species Facts Scaleshell Mussel Leptodea leptodon The scaleshell is a freshwater mussel that was listed in 2001 as an endangered species by the U.S. Fish & Wildlife Service. Endangered species are animals and plants that are in danger of becoming extinct. Threatened species are animals and plants that are likely to become endangered in M.C. Barnhart Photo by Dr. the foreseeable future. Identifying, protecting, and restoring endangered and threatened species is the primary objective of the U.S. Fish and Wildlife Service’s endangered species program. Once present throughout most of the eastern United States, the scaleshell What is a scaleshell mussel? mussel is now found only in Arkansas, Missouri, and Oklahoma. Appearance - The scaleshell is a relatively small freshwater mussel with a thin, fragile shell and faint roles of scaleshell in river water quality from pollution because green rays. It grows to about one ecosystems are as food for wildlife they are sedentary (stay in one to four inches in length. The inside like muskrats, otters, and raccoons place). Pollution may come from of the shell is pinkish white or light and as filters which improve water specific, identifiable sources such as purple and highly iridescent. The quality. factories, sewage treatment plants scaleshell gets its name from the and solid waste disposal sites or scaly appearance of the shell, Reproduction – The life cycle of from diffuse sources like runoff from which is only seen in females.ll the scaleshell, like most freshwater cultivated fields, pastures, cattle mussels, is unusual and complex. feedlots, poultry farms, mines, Range - Scaleshells historically Their eggs develop into construction sites, private occurred across most of the microscopic larvae (glochidia) wastewater discharges, and road eastern United States. During the within the gills of the female. The drainage. Contaminants reduce last 50 years this species became female discharges its glochidia into water quality and may directly kill increasingly rare within a reduced the river where they must attach mussels, reduce the ability of range. Of the 55 historical to gills or fins of a fish to continue surviving mussels to have young, or populations, 14 remain scattered developing. Each mussel species result in poor health or within the Mississippi River basin has specific fish species (host fish) disappearance of host fish. in Arkansas, Missouri, and that are needed by the glochidia to Oklahoma. develop. Freshwater drum were Sedimentation - Sediment is identified as a host fish for the material suspended in water that Habitat - Scaleshell live in scaleshell but there may be other usually is moved as the result of medium-sized and large rivers with species. Glochidia continue growing erosion. Although sedimentation is a stable channels and good water on the fish and transform into natural process, poor land use quality. They bury themselves in juveniles. After a few weeks they practices, dredging, impoundments, sand and gravel on the bottom with drop off and land on the river bottom intensive timber harvesting, heavy only the edge of their where they grow into adults. recreational use, and other partially-opened shells exposed. As activities may accelerate erosion and river currents flow over them, they Why is the scaleshell mussel increase sedimentation. A sudden or siphon particles out of the water for endangered? slow blanketing of the river bottom food such as plant debris, plankton, Pollution - Adult mussels are easily with sediment can suffocate and other microorganisms. The harmed by toxins and declines in freshwater mussels because it is difficult for them to move away from watersheds. Habitat restoration will properly disposing of or the threat. Increased sediment require improvements across the recycling hazardous materials levels may also make it difficult for entire watershed. The voluntary found in your home, like scaleshells to feed, which can lead to assistance of Federal and State batteries, paint, car oil, and decreased growth, reproduction, and agencies, conservation groups, local pesticides. survival. governments, private landowners, industries, businesses, and farming • Join a conservation group or Dams - Dams affect both upstream communities will be necessary to volunteer at a local nature and downstream mussel populations meet recovery goals. The role of center, zoo, or wildlife refuge. by disrupting natural flow patterns, private landowners and businesses is scouring river bottoms, changing important as land in watersheds water temperatures, and eliminating occupied by scaleshell are primarily habitat. The scaleshell, a mussel privately owned. adapted to living in river currents, cannot survive in the still water Recovery Plan - The U.S. Fish and impounded behind dams. Wildlife Service prepared a recovery plan that describes Scaleshells depend on their host fish actions needed to help the as a means of moving upstream. scaleshell survive. Some of these Because dams are barriers that include: 1) stabilizing existing prevent fish from moving upstream populations through artificial they also prevent mussels from propagation; 2) utilizing existing moving upstream. Upstream mussel legislation, regulations, and populations then become isolated programs to protect remaining from downstream populations. This populations and habitat; 3) conduct isolation leads to small unstable research on critical aspects of its populations which are more likely to biology needed to manage the die out. species and to identify harmful pollutants; 4) establish a recovery Exotic Species - The invasion of the implementation team to apply exotic zebra mussel into the U.S. sound science to recovery and poses a substantial threat, because it foster partnerships; 5) work with starves and suffocates native willing partners to protect existing mussels by attaching to their shells populations and habitat, eliminate in large numbers. threats, restore habitat, and improve surface land in What is being done to prevent the watersheds, and 6) carry out an extinction of the scaleshell? outreach and education to heighten Listing - The scaleshell was added awareness of scaleshell and to to the U.S. List of Endangered and solicit outside help with recovery Threatened Wildlife and Plants on actions. October 9, 2001, providing Endangered Species Act (ESA) What can I do to prevent the protection. The ESA also requires extinction of species? that a Recovery Plan be prepared • Learn more about how the for listed species. destruction of habitat leads to loss of endangered and Watershed Protection Through threatened species and our Partnerships - The scaleshell nation’s plant and animal cannot survive without soliciting diversity. Discuss with others outside help to restore habitat and what you have learned. improve surface lands. Causes of habitat degradation are numerous • Support local and State in streams throughout its range. initiatives for watershed and U.S. Fish & Wildlife Service In many cases, the threats are not water quality protection and 1 Federal Drive from actions in or adjacent to the improvement. rivers where the species is found. Fort Snelling, Minnesota 55111 Instead, threats are due to • Help improve water quality 612/713-5350 widespread problems originating on locally in streams by minimizing http://www.fws.gov/midwest/endangered uplands at the highest elevations of use of lawn-care chemicals and April 2010.