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- While Ann Arbor's landscape has been altered greatly since pre-settlement times, there remains a high diversity of native ecosystems and species. Natural Area Preservation staff are working with hundreds of volunteers, other local organizations, and private landowners to document, maintain, and enhance ecological diversity throughout Ann Arbor.
Source: Ann Arbor Natural Area Preservation |
What is biodiversity?
Biodiversity describes all life on earth and the systems that support life on earth. Two types of biodiversity include ecosystem diversity and species diversity.
Ecosystem Diversity
An ecosystem is defined by the physical components (air, water, minerals, energy) and the biological components (plants, animals, microorganisms) in its environment. The landscape and vegetation communities in Ann Arbor developed over thousands of years in response glacial movement, soil types, moisture gradients, and fire. Each ecosystem is home to a variety of native plants and animals that together contribute to a region’s biological diversity.
Although the proportion of land in each ecosystem type has changed significantly since European settlement, Ann Arbor natural areas still represent a diversity of ecosystem types including woodlands, wetlands, prairies, and savannas.
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Woodlands dominated Ann Arbor’s landscape when European settlers arrived in 1824. Forest communities contained diverse herbaceous plants and mature trees. Many of these woodlands were cleared in the 1800s for timber and agriculture, but some remnant forest fragments remain. Forest, Bird Hills, Kuebler-Langford, Cedar Bend, and South Pond Nature Areas contain examples of woodland communities such as wet forest, mesic forest, and dry forest.
- Ann Arbor wetland communities, characterized by non-woody vegetation and seasonal to year-round standing water, are most concentrated along the Huron River. Wetlands are extremely valuable because they absorb flood waters and filter run-off. Emergent marshes provide habitat for a diversity of dragonflies and damselflies, birds, and amphibians. Wet meadows, which are inundated with water for only part of the year, offer habitat for many species of butterflies and nesting birds. Furstenberg Nature Area contains excellent examples of emergent marsh and wet meadow communities.
- Small pockets of prairie, or grassland, and savanna, or partially forested grassland were found throughout the Ann Arbor area. Many of these native ecosystems were detroyed for agriculture, then urban development, or have been taken over by invasive vegetation. Prairie ecosystems are being actively restored throughout the City. Barton, Bandemer, and Furstenberg Nature Areas and Gallup Park have good examples of prairie communities. The Gallup Park wet prairie is one of the last remaining examples of wet prairie in the entire state of Michigan.
Species Diversity
Natural Area Preservation has inventoried plants and animals in the City’s natural areas and has found over 1500 plant species and 300 animal species, including 197 species of migratory and summer resident birds, 80 species of butterflies, 10 species of frogs and toads, 6 species of salamanders, 4 species of snakes, and 3 species of turtles.
Natural areas such as Bird Hills and Furstenberg contain over 300 native plant species each, making them important reserves of biological diversity. Despite the positive effects of preservation of these natural areas, wildlife habitat continues to decline due to land-use changes and invasive species.
How is the City of Ann Arbor working to maintain and increase ecological biodiversity?
In 1993, the City created the Natural Area Preservation (NAP) Division to protect and restore Ann Arbor’s natural areas and to foster and environmental ethic among city residents. NAP staff and volunteers work to protect natural areas with high species diversity from degradation and to restore severely disturbed natural areas. NAP’s activities include:
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Last Updated September 2009