Thus, it is initially important to define which structures and activities are being analyzed for impacts, and to identify how they may affect ESA-listed species. Adverse impacts on listed species can result from construction or maintenance activities, or from the existence of the structure. Proposed projects having a federal nexus are analyzed for potential impacts at a variety of levels. Direct impacts to a listed species could occur from water quality impacts during construction, or result from increased opportunities for predation from the presence of a new pier. Such a take would be a direct effect.
Indirect effects are less obvious.
The reduction in water quality that might occur from a fuel spillage during boat fueling at a new residential pier would be an indirect effect. If the pier had not been constructed, the fuel spill would not have occurred. The Services are concerned about potential adverse impacts of shorezone development on juvenile and adult chinook and coho salmon, and bull trout. Any reduction in aquatic vegetation may also reduce complex refuge habitat. To date, the Services have made no distinction between native and non-native aquatic vegetation.