Our inventory of vacant land for restoration and protection in and along the Detroit River found 104 candidate sites covering 3,433 acres (ac) of terrestrial and aquatic land that contains, or could serve as, fish and wildlife habitat. These candidate sites were almost equally divided between public (53.3%) and private (46.5%) ownership. The majority of the 1,855 ac of public land is either Grosse Ile open space land (524.9 ac) or parks (430.5 ac). Habitat for fish and wildlife could be protected or restored on such land mainly because: (1) public land is largely unavailable for development, and (2) public land is governed by the state and local communities, and therefore can be conserved or restored as habitat. We subjectively determined that 30 of the public sites (1,404 ac) were “productive” of fish and wildlife and have significant habitat value. By the same means, we determined that 20 of the privately owned sites (791.6 ac) possessed significant habitat value.

Industrial sites and brownfields made up the majority of the privately owned sites. Of these, the Humbug Marsh complex and various islands in the Conservation Crescent (Jones, 1997) had significant habitat value. More than 933 ac of brownfields along the Detroit River presented a unique opportunity for habitat restoration. Most brownfields were former industrial sites that have been cleared of their structures and could be redeveloped. These sites may require some decontamination and environmental remediation. Some real gains could be made for fish and wildlife habitat in the private sector. Tax breaks, zoning approvals, or positive media attention could all be used as incentives for private developers to include an “habitat restoration initiative” in their development plan. Natural area or tree cover, a riparian buffer near the shore, and most importantly soft engineering of the shoreline (Caulk et al, 2000) are all habitat restorations that could be included in brownfield remediation plans.

Treatment of the shoreline was often extensive along the riverfront. Of the sites we surveyed along the riverfront, 73% were armored. The most prevalent type of shoreline treatment was reinforced concrete wall. More than 4 miles of this wall were present in the 11.2 miles of mainland shoreline included in this study. This wall is an abrupt end to the littoral zone, denying fish shallow water in which to spawn or feed, preventing small mammals access to the river, and leaving no place for riparian vegetation to grow. Concrete riprap is another common shoreline reinforcement that is detrimental to natural river processes and fish habitat (Schmetterling, 2001). Large broken pieces of concrete and limestone are commonly stacked and scattered along the shore to prevent erosion. This treatment covers most natural earthen shoreline, prevents vegetation growth and encroaches severely on the littoral zone and its biological function. These treatments prevent the transfer of sediment and nutrients through the littoral zone, and cause the Detroit River to deposit most of its suspended sediments into western Lake Erie.

Potential habitat for fish and wildlife existed along the Detroit River in 2000, but more scientific research is needed to assess the quality of this habitat, and rank each site for protection and enhancement. Present knowledge of habitat productivity and biodiversity at these candidate sites is superficial. Further research is needed to quantify their habitat value. A simple biodiversity index could establish which species exist at each site and the frequency of their occurrence among the sites. Analyzing the plant species that are documented in the biodiversity index with a method such as the Floristic Quality Index (Herman et al, 1996) could partly establish the biological value of each site. Analyzing vegetation as an indicator of site quality could determine the level of disturbance at each site, the annual hydrologic conditions, and the suitability of each candidate site for fish and wildlife species of interest. For now, we subjectively sorted the “productive” sites from the rest and labeled them as either “protected productive” or “unprotected productive” to identify the candidate sites having the most habitat potential. To accurately categorize and prioritize fish and wildlife habitat along and in the Detroit River for conservation of natural resources, we could quantify the biological diversity of these sites with a more thorough scientific assessment.