The diverse mosaic of habitats (forests, wetlands, grasslands, and aquatic habitat) in the Coastal Bays watershed are threatened. Forests, largely a mixture of pine and hardwood, are a dominant land type, with planning and growth projections predicting significant losses in the next 20 years. Another important habitat is wetlands. An estimated 41% of historic wetlands have been lost to development, erosion, ditching, farming, and logging activities.
Despite current regulations to protect wetlands, sea level rise will exacerbate future losses. Conservation of grassland habitat has been successful in providing wildlife habitat and reducing nutrient runoff. Assuming 95% of the watershed was historically forested, only 42% of Maryland’s watershed remains forested. Although croplands pale in comparison to forests or wetlands for habitat value, agricultural lands can be important to many species and need to be preserved from development. Terrestrial habitat in the northern bays is more degraded due to development, while the southern bays have more undeveloped and protected lands. Storms are a primary natural force shaping coastal habitat, driving landscape level changes essential to the health of the ecosystem.
Effects of erosion on Assateague Island
The continued existence of bay islands as habitat is critical for certain water birds. The shifting sands of Assateague and Fenwick Islands epitomize the interactions between land and sea. Aquatic habitats are stressed. Streams that connect the land to the bays are in poor condition as a result of ditching and excessive nitrate levels. Sea level rise and erosion are additional factors altering aquatic habitat and changing bottom type.
Historically, seagrass acreage has been dynamic. Seagrass coverage expanded to the greatest levels ever recorded in the Coastal Bays in 2000, but then suffered significant declines in 2005. In 2004–2006, only 48% of the seagrass goal was being met.
Variations in goal attainment were related to differences in water quality. Loss of seagrass will have a cascading effect on ecosystem health by reducing aquatic species (e.g., scallops), water quality, and other living resources (e.g., Atlantic brant).