Scientists, governments, and many concerned citizens throughout the world recognize the value of biodiversity and are working to protect species that are threatened with extinction. In 1973, the United States passed a law called the Endangered Species Act, which is designed to protect species that might otherwise be headed to extinction. Today, more than 1000 different animals and plants in the United States have been listed as endangered (a species in danger of extinction), and even more are listed as threatened (meaning that their populations have declined rapidly). In 1974, the Michigan Endangered Species Law (Part 365 of PS 451 of 1974) was passed to provide specific protection to Michigan species. As of 2011, 21 species in Michigan were protected by the Federal Endangered Species Act and approximately 400 species were listed as endangered or threatened under the Michigan Endangered Species Law.

Sorting Out the Terms

• Special Concern: Populations that are declining and, if allowed to continue to decline, may become threatened or endangered. Not legally protected.

• Threatened: A species that is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.

• Endangered: A species that is in danger of extinction throughout all or a significant portion of its range.

• Extinct: A species that no longer exists on Earth.

• Extirpated: A species that is locally extinct, for example no longer occurring in Michigan but surviving in other parts of its range. The massasauga no longer occurs in several counties in Michigan and is, therefore, extirpated in those counties. The species is not extinct; however, because it occurs in other counties.

The Michigan Natural Features Inventory (MNFI) maintains a list indicating the county distribution of Michigan species listed as endangered, threatened, or of special concern. This list is available at the MNFI web site (refer to Additional Resources section at the end of this lesson). The list is an excellent resource for identifying what listed (those that are threatened or endangered) species inhabit specific counties in Michigan.

The loss of habitat is the number one threat to biodiversity worldwide. Other causes include the introduction of invasive species, pollution, pressures from population growth, overuse of resources, and disease. Conservation techniques that preserve and restore habitat are crucial to maintaining biodiversity. An excellent extension to this lesson and conclusion to this unit would be to have students plan and develop a wildlife habitat project on the school grounds. (See the Additional Resources section for helpful materials.)

Total Number of Listed Animals and Plants in Michigan, 2011