Key Threats to the
American Dipper in the Black Hills
STREAM POLLUTION
Sediment pollution, heavy metal pollution, acid mine drainage, and pollution associated with sewage systems have all been documented to harm the American dipper. Pollution degrades stream habitats and is detrimental to aquatic insects - the primary food of the dipper. Several streams on the Black Hills have suffered and continue to suffer from pollution problems, threatening aquatic insects and the dipper.
LIVESTOCK GRAZING
Livestock grazing in and near streams degrades American dipper habitat. Also, research has found dippers are absent along streams that have been heavily grazed. Grazing occurs in and near streams in the Black Hills and threatens the dipper.
LOGGING
Logging near streams and on steep slopes degrades dipper habitat by causing sediment pollution from increased erosion. Logging has occurred and continues to occur on virtually every acre of the Black Hills, near streams, and on steep slopes and continues to threaten the dipper
ROADS AND ROAD CONSTRUCTION
The existence of roads and the construction of roads all lead to increased erosion and sediment pollution, which degrades dipper habitat. The Forest Service estimates that 5,204 miles of system roads and 3,430 miles of user-created roads exist on the Black Hills. Additionally, several hundred miles of roads are slated for construction in the next decade.
MINING
Mine pollution can physically harm American dipper and degrade their habitat. Mine pollution on the Black Hills continues to plague several streams, including Spearfish Creek, and threatens the dipper.
DAMS AND DIVERSIONS
Dams and diversions can lead to reduced or erratic stream flows, all of which can affect the American dipper by destroying nests and nesting habitat, causing winter habitat to freeze over, and increasing stream pollution. On the Black Hills, erratic flows from Pactola Dam and have contributed to the loss of the dipper on Rapid Creek while many water diversions have reduced streams flows and further threaten the bird.
OTHER THREATS
Groundwater extraction and the loss of beaver in the Black Hills have all lead to decreased stream flows. Recreational activities and developments also have the potential to harm the dipper if not properly managed. Additionally, because of the small population size and isolation of the American dipper in the Black Hills, the bird is more vulnerable to extinction from fires, floods, and severe winter weather.
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