Rapid expansion in Detroit over the last century has meant high levels of pollution for the city’s river. The situation was so critical at one point that fish could not survive in the waters and migrating birds would die because of a high concentratio of oil. In 2001 the Detroit River International Wildlife Refuge was founded when American Congressman John Dingell advocated for a sustainable ecosystem: “In 10 years the lower Detroit River ecosystem will be an international conservation region where the health and diversity of wildlife and fish are sustained through protection of existing significant habitats and rehabilitation of degraded ones”. He was right. In less than two decades, many habitats have been restored, and a lot of species of birds, fish, and mammals have begun to dwell in the area again. This refuge also houses ancient plants thriving despite massive agriculture and industrialization: some remaining marsh forests in the downriver area are providing biologists with a valuable snapshot into past habitats. Today, the Detroit River International Wildlife Refuge covers the only international wildlife preserve in North America, from the heart of a major metropolitan area.