The term "endangered" characterizes a species that is in danger of extinction throughout the area in which it is usually found, according to the U.S. Fish and Wildlife. Federal and state laws protect endangered animals across the United States. In Wisconsin, State Statute 29415 and Administrative Rule NR27 guarantee the protection of more than 50 species, including many birds, mammals and mollusks, according to the Wisconsin Department of Natural Resources.
Wisconsin has protected the gray wolf since 1957, after the species was extinguished in the state because of excessive hunting. Gray wolves started to be monitored in Wisconsin through a radio-collar in 1979, when only 25 wolves were found in the state. However, according to the U.S. Fish and Wildlife Service, the wolf population increased from 83 to 549 wolves from 1985 and 2008.
Winged mapleleaf (Quadrula fragosa) is a freshwater mussel. It has greenish brown or dark brown thick shells, with several rows of bumps unique to this species. They are found in the St. Croix River, and are currently threatened by the invasive zebra mussel, which competes for food and space. Native of Russia, zebra mussels were introduced to North America in the late 1980s.
The Kirtland's warbler (Dendroica kirtlandii) is a songbird currently endangered in Wisconsin, according to data published by the U.S. Fish and Wildlife Service. These birds migrate to the southeastern coast of the United States and Bahamas during winter. In 2008, after a government program of monitoring and controlling parasitic brown-headed cowbirds, the main threat to Kirtland's warbler recuperation, at least 10 chicks warblers survived to leave their nests.
