Research: Nearshore Habitats and Coastal Stressors
Shallow water fish communities and coastal development stressors in the Lynnhaven River
Coastal development pressures in the Mid-Atlantic have been attributed to significant negative impacts to aquatic ecosystems. The Lynnhaven River watershed, located in the southernmost extent of the Chesapeake Bay and encompassing Virginia Beach, is an example of a shallow-water tidal system under intense development pressure that is confronted with multiple and often conflicting coastal management issues. Rapid development in and around the City of Virginia Beach over the past few decades has led to the loss of natural buffers and habitat (e.g. oyster, wetlands and seagrasses), increased sedimentation, and degraded water quality. The Lynnhaven Ecosystem Restoration Project, led by U.S Army Corps of Engineers, is an effort to collaborate with State and federal partners over a 5-year period to identify and implement the most effective strategies for improving water quality, restoring oysters and seagrasses, and managing siltation.
Limited quantitative information exists on the fish assemblages utilizing shallow water habitats, such as tidal creeks, within the Lynnhaven River restoration area. To document nekton composition, and to investigate potential effects of development stressors, such as dredging and shoreline modification, three sets of paired dredged and undredged tidal creeks were surveyed in the Western Branch of the Lynnhaven River. Fish communities were sampled with multiple gear types once per month for three months (August, September, October, 2006). Abundance, average length and weight, diversity, and fish community indices were estimated for each creek and time period, and dredged compared with undredged systems for resemblance in fish composition and abundance. Tidal creeks within Lynnhaven Bay support diverse and similar fish communities. Slight differences in community structure among creeks may be attributable to the location and size of watersheds. The effects of dredging were not apparent in fish community responses measured as abundance, biomass, diversity, and fish community indices. However, anthropogenic effects may be obscured in the short-term by the background variability of physical and water quality features of Lynnhaven Bay estuary, and long-term or cumulative effects are not quantifiable due to the dearth of historic information on fish communities. Available historic information may indicate a shift in fish community structure that could be associated with coastal development pressures, such as shoreline alteration and habitat loss of wetlands and oyster reefs. Accordingly, restoration and preservation of critical nursery habitats may augment fish productivity in Lynnhaven Bay. Shallow water use project objectives
Assess tidal creek fish community characteristics in Lynnhaven Bay
Compare fish communities in dredged and undredged tidal creek systems
Inventory shoreline condition in Lynnhaven Bay -- including land use, structures and bank conditions
Final Report for Lynnhaven Fish Communities.