ML12184A302
| ML12184A302 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar  |
| Issue date: | 03/28/2011 |
| From: | US Dept of Interior, Fish & Wildlife Service |
| To: | Watts Bar Special Projects Branch |
| Poole J | |
| References | |
| Download: ML12184A302 (2) | |
Text
U.S. Fish & Wildlife Service Sheepnose (a freshwater mussel)
Plethobasus cyphyus The sheepnose is a freshwater mussel that the U.S. Fish and Wildlife Service has proposed to list as an endangered species.
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 the foreseeable future. Identifying, Photo by USFWS; Kristen Lundh protecting, and restoring endangered and threatened species are primary objectives of the U.S.
Fish and Wildlife Services endangered species program.
What is a sheepnose mussel?
Appearance: The sheepnose is a medium-sized mussel that grows to about 5 inches in length. The shell is The shell of the sheepnose is extremely hard, so much so that clammers on the thick and solid, with the overall Cumberland River called it clear profit because they were the only ones who get shape slightly longer than wide and anything out of it as it was too hard for making buttons.
somewhat inflated.
Missouri, Ohio, Pennsylvania, food in appearance. These The sheepnose shell is smooth, Tennessee, Virginia, West Virginia, conglutinates are narrow, red or shiny, and light yellow to a dull and Wisconsin. pink, and discharged in unbroken yellowish brown and without lines or form so that they look like small rays but with dark concentric Reproduction: The life cycle of the worms. When a fish eats a ridges. The ridges result from sheepnose, like most freshwater conglutinate, glochidia are exposed periods when growth stops or slows. mussels, is complex and includes a to and can attach to the fishs gills.
stage that is parasitic on fish.
Range: The sheepnose is found Initially, males release sperm into If glochidia successfully attach to a across the Midwest and Southeast. the water current. As female host fish, they mature into juvenile However, it has been eliminated from mussels siphon water for food and mussels within a few weeks and then two-thirds of the total number of respiration, they also siphon sperm drop off. The sauger (Stizostedion streams from which it was that fertilizes their eggs. Within canadense) is the sheepnose historically known (24 streams are special gill chambers, fertilized eggs mussels only known host, but others currently occupied compared with 77 develop into microscopic larvae may be available. After dropping off, streams historically), and it has also called glochidia. Female mussels glochidia continue to grow and been eliminated from hundreds of expel the mature glochidia, which mature if they land in suitable areas.
miles of rivers in the Illinois and then must attach to gills or fins of a Using fish as hosts allows the Cumberland River basins, and from specific host fish species to complete sheepnose to move upstream and several reaches of the Mississippi development into a juvenile mussel. populate habitats it could otherwise and Tennessee Rivers. The not reach.
sheepnose is currently found in Sheepnose expel glochidia in Alabama, Illinois, Indiana, Iowa, conglutinates, a jellylike mass of As a group, mussels are long-lived, Kentucky, Minnesota, Mississippi, mucus and glochidia, that mimic fish with individuals living up to several
decades, and possibly up to 100, and even Pollution may come from specific, nuisance species laws, monitoring, and 200 years. Sheepnose, especially identifiable sources such as accidental providing information for boaters at water thick-shelled individuals from large rivers, spills, factory discharges, sewage access sites.
are thought to live longer than other treatment plants, and solid waste disposal mussel species, however, we have no age sites. Pollution also comes from diffuse Monitoring and Research: Many states information. sources like runoff from fields, feedlots, with sheepnose populations and some mines, construction sites, private federal agencies are conducting surveys Habitat: Sheepnose mussels live in larger wastewater discharges, and roads. and funding research to find out about the rivers and streams where they are usually Contaminants may directly kill mussels, sheepnose mussels specific life history found in shallow areas with moderate to but they may also indirectly harm requirements and threats to its survival.
swift currents flowing over coarse sand and sheepnose by reducing water quality, gravel. Sheepnose have also been found in which reduces survival and reproduction, What can I do to help prevent mud, cobble, and boulders. In larger rivers and lowers the numbers of host fish. the extinction of species?
they may be found in deep runs. Learn more about how the destruction of Channelization: Dredging and habitat leads to loss of endangered and Feeding Habits: Adults are channelization have profoundly changed threatened species and our nations plant suspension-feeders, siphoning in water and rivers nationwide. Channelization and animal diversity. Discuss with others feeding on the suspended algae, bacteria, physically alters rivers by accelerating what you have learned.
detritus, microscopic animals, and erosion, reducing depths, decreasing dissolved organic material. Adult mussels habitat diversity, destabilizing stream Help improve water quality in your local spend their entire lives partially or bottoms, and removing riparian vegetation. streams by minimizing use of lawn-care completely buried within the substrate. chemicals and properly disposing of or Small Population Size and recycling hazardous materials found in What are threats to the Fragmentation: Most populations of your home, like batteries, paint, car oil, sheepnose mussel? sheepnose are small and geographically and pesticides.
isolated. These small populations, which Dams: Dams affect both upstream and live in short sections of rivers, are downstream mussel populations by When boating, please follow rules susceptible to extirpation from single established to prevent the spread of disrupting natural river flow patterns, catastrophic events, such as toxic spills.
scouring river bottoms, changing water exotic pests like the zebra mussel.
Also, isolation makes natural repopulation temperatures, and eliminating habitat. impossible without human assistance.
Large rivers throughout most of the Join a conservation group or volunteer at sheepnose mussels range have been a local nature center, zoo, or wildlife Nonnative Species: The invasion of the impounded; leaving short, isolated refuge.
nonnative zebra mussel into the United patches of habitat below dams. States poses a serious threat. Zebra The sheepnose also depends on host fish mussels proliferate to such an extent to move upstream. Because dams block that they deplete food resources and fish passage, mussels are also prevented they attach to native mussel shells in from moving upstream, which isolates such large numbers that the native upstream from downstream populations, mussel cannot open its shell to eat or leading to small, unstable populations, breath.
which are more likely to die out.
What is being done to conserve Sedimentation: Poor land use practices, and restore sheepnose mussels?
dredging, intensive timber harvests, road Listing: The sheepnose mussel was construction, and other activities may designated by the U.S. Fish and Wildlife accelerate erosion and increase Service as a candidate species for listing as sedimentation. Sedimentation that results threatened or endangered under the in blanketing a river bottom may Endangered Species Act. The Service is suffocate mussels because they cannot now proposing to list it as endangered. If move fast enough to avoid the impact. listed, the sheepnose will receive the full Also, increased sedimentation reduces the protection of the Endangered Species Act, ability of mussels to remove food and which provides protection against certain oxygen from the water, which can lead to practices and would require planning for decreased growth, reproduction, and recovery.
survival. U.S. Fish & Wildlife Service Prevent or Slow Spread of Zebra 1 Federal Drive Pollution: Adult mussels are easily Mussels: States and Tribes are working Fort Snelling, Minnesota 55111 harmed by toxins and degraded water to prevent the spread of zebra mussels to 612/713-5350 quality from pollution because they are areas such as the northern portions of the http://www.fws.gov/midwest/endangered sedentary (they tend to stay in one place). St. Croix River, by enforcing aquatic January 2011