Endangerment
The Appalachian elktoe was added to the Federal Register of Endangered Species on November 23, 1994. The exact cause for the decline of the species is unknown. Many factors have been blamed for the endangerment, including siltation] from logging, mining, common agricultural practices, and also area construction work. Runoff into the river systems can seriously affect the species' survival, since the mussels only live in clean, well-oxygenated streams. The runoff and discharge of pollutants from industrial, agricultural, and municipal sources can cause major damage to the sensitive species. Human alterations of the species' habitat, such as dredging, damming, and other forms of channel manipulation, also have been considered responsible for declining populations. Changing aquatic environments without proper sedimentation control does not only negatively affect river mussels, but most other freshwater species as well.
Mussels are somewhat stationary; they are unable to move long distances, which is why they live in very specific, stable habitats that fulfill all of their needs. Their immobility hinders their survival, because they are unable to adapt to constantly changing aquatic environments. When their habitat is constantly being tampered with, they are unable to fully develop and reproduce.
The species was first noticed to be declining in populations some time after Hurricane Frances and Hurricane Ivan hit the Southeastern region of the United States in the early 1990s. Although the landscape was changed due to the high winds and heavy rain of the hurricanes, naturally occurring storms do not threaten the Appalachian elktoe. When humans tamper with the naturally occurring state of the streams however, it is very difficult for the Appalachian elktoe, as well as other mussel species, to remain healthy.
Siltation in the rivers is one of the biggest threats to freshwater mussels. Naturally occurring siltation usually does not bother the species, because it is on a much smaller scale. Siltation caused by human interaction both directly and indirectly affects mussels: it causes the natural patterns of the rivers to change. It can also create mounds on the bottom of the streams, which not only cover the rocks that mussels prefer to live next to, but also creates areas in the water that are difficult for the mussels' host fish to swim in, causing serious species fragmentation.
Siltation also degrades the quality of the water and exposes mussels to many more pollutants than they would naturally be exposed to. A study done in 1936 found that even one inch of unnatural sedimentation in the habitat causes high mortality rates in most mussels, including the Appalachian ekltoe (Ellis). Juveniles and reproduction are also seriously affected by even small amounts of sedimentation. When the clean, well-oxygenated water of the mussels' habitat gets a certain amount of sedimentation, the juveniles are not able to develop properly, because the silt clogs the gills of the host fish that they parasitize themselves on. Most mussels are sensitive to many pollutants, and some of the most harmful pollutants are different forms of heavy metals, higher than normal concentrations of nutrients, and chlorine.
Because of the irregularity of the habitat of the Appalachian elktoe and similar mussel species, on September 27, 2002, over 144 miles (232 km) of river area in western North Carolina and eastern Tennessee were deemed critical habitat. Critical habitat is an area that the government has reserved for monitoring and protecting, in an effort to save species currently inhabiting that area. By declaring the Appalachian elktoe's habitat critical, it allows for management plans to be fully implemented and for penalties or fines to be created for partaking in activities that may lead to the species' decline.
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