Dr. David L. Strayer Freshwater Ecologist Share: April 1, 2012 Hudson River, Shore Zones 1. Preserve physical diversity Complex habitats usually support more species and ecological functions than those that are simple. Resist the urge to grade everything smooth, use the same materials everywhere, and build straight shorelines. Shore zones that have uneven topography, varied soils and vegetation, and irregular shorelines are likely to provide better ecological value. 2. Resist tidiness “Debris” such as driftwood and windrows of vegetation along the shore provide perching spots for birds, cover for fish and other animals, nursery areas for young plants and animals, and food for the little animals that feed birds and fish. It’s ok to pick up garbage like plastic, paper, and glass, but messy shore zones are better for ecological function than shore zones that look like Martha Stewart’s living room. Tidy, structurally simple shore zones like this one offer little habitat for plants and animals, and may be inhospitable to animal migration. 3. Don’t squeeze the shore zone! It seems obvious that if you squeeze the shore zone out of existence by dredging or filling the shallows and wet areas, building vertical walls, and destroying vegetation, you will eliminate its ecological value. However, that’s just what people have been doing for thousands of years. So don’t. 4. Prevent pollution Pollution released into the shore zone can both damage the shore zone itself and easily move into nearby waters. Try to avoid land uses in and adjacent to the shore zone that could release or spill pollutants. It’s also a good idea to use as little fertilizer and pesticide as possible in the shore zone. 5. Reduce wave damage Large waves, whether from the wind or passing boats, can damage shore zones. Offshore dredging and shoreline hardening can increase wave damage by removing the natural structures that absorb wave energy. Reduce the damaging effects of waves by limiting these activities, and consider imposing no-wake zones near sensitive shorelines. Vertical walls can block animal migrations and reflect wave energy, and should be avoided. 6. Tread lightly Shore zones are popular places for fishing, swimming, bird-watching, boating, hiking, and other recreational activities. Unfortunately, these activities can sometimes damage shore zones by frightening away animals, trampling plants and animals, and eroding shores and soils. So watch for signs of overuse, consider protecting parts of your shore zone as refuge areas where human activities are restricted, or prohibit some activities during sensitive times such as breeding seasons. 7. Don’t make dead ends Animals (and plant seeds, too) use shore zones as highways when they’re migrating, seeking sites to nest or feed, or recolonizing areas that were disturbed by nature or humans. When we put sterile habitat like a seawall or a parking lot along the shore, or build walls or roads that keep animals from moving between the water and the land, we block those highways and so damage shore zone biodiversity. Try to preserve continuity of habitat along the shore zone both above and below the water line, and avoid building walls, curbs, and other barriers that block shore zone animals. Leaving intact vegetation above and below the water line provides good habitat for plants and animals. 8. Don’t make it so hard! Many natural shore zones are made of a mixture of materials, including “soft” materials such as sand, mud, and gravel, often covered with vegetation. Humans frequently replace such soft materials with large stone, concrete, or steel. These hard materials change habitats and reflect waves, leading to erosion offshore and on adjacent properties. Where possible, try not to replace naturally soft shores with hard materials, and try to soften existing hard shorelines. 9. Give the shore room to move If you hem in a shore zone by building right up to its edges, it will be squeezed away when water levels rise. This will reduce or eliminate its ecological value, so wherever possible, give shore zones room to move. Because we’ve already hemmed in many shore zones with homes and other valuable infrastructure, this will be hard to do for many sites. But where it is possible, this is an important strategy to preserve ecological functioning in the face of rising water levels in the coming century. 10. Be careful about building in the shore zone If you must build in the shore zone, reduce ecological impacts by using permeable materials that let water soak into the ground, minimizing roads, walls, and curbs that block animal movement, and limiting bright lights that attract emerging aquatic insects. Nature trails and parks may be better uses of the shore zone than buildings and hard structures. Share: Dr. David L. Strayer Freshwater Ecologist Dave Strayer is a freshwater ecologist whose work focuses on measuring the long-term effects of zebra mussels on the Hudson River ecosystem, and understanding the roles of suspension-feeding animals in ecosystems. Strayer also works on broader issues in freshwater conservation ecology and invasion biology.