I. Habitat Description
The shallow marsh perennials habitat includes portions of lakes, ponds, backwaters, or shorelines that are seasonally flooded and more than 10% vegetated with persistent emergent vegetation. This habitat denotes the transition zone between deep marsh perennials and wet meadow. Common plant species are common cattail (Typha),perennial smartweeds (Polygonum), giant reed (Phragmites), and bulrush (Schoenoplectus). Invasives include purple loosestrife. This habitat may have inclusions of submersed, nonrooted-floating aquatics, or other emergent vegetation. It is typically found growing on soils that are saturated or inundated by water up to 0.2 meters deep. During normal water conditions, there is little flow, though there can be wind-generated currents and stronger flows at inlets and outlets. During flood conditions, these habitats can be connected to rivers or streams, with strong currents and possibly large amounts of debris.
II. Sensitivity to Oil Spills
The shallow marsh perennials habitat is high sensitive to oil spills. This habitat is valuable to a variety of birds, amphibian, reptile, and mammal species as well as micro and macro invertebrates, many of which are extremely sensitive to chemical exposure. During normal water levels, oil would be less likely to penetrate water-saturated soils; during floods, oil could be deposited in areas that dry out after the flood, and penetrate the loose, organic-rich surface soils. Light refined oils with high amounts of water-soluble fractions can cause acute mortality to animals and plants. Heavier oils tend to coat vegetation, which may survive if oil coats only the stems or if the roots are unaffected. It is difficult for more viscous oils to penetrate densely vegetated areas.
III. Sensitivity to Response Methods
The following text describes potential adverse impacts to this habitat resulting from various oil spill response methods and provides recommendations to reduce impact when these methods are implemented. This is not intended to preclude the use of any particular methods, but rather to aid responders in balancing the need to remove oil with the possible adverse effects of removal. More detail about the response methods themselves can be found in the Inland Response Tactics Manual.