Seagrass Depth Limits in Chincoteague Bay

Knowledge of seagrass depth limits is essential in the understanding of seagrass distributions locally and at global scales. They also depend on sediment characteristics, nutrient levels, and other factors. Depth ranges vary with species depending on rhizome structures and complexity of seagrass species. Seagrass communities are a major part of marine ecosystems responsible for organic matter production and carbon sequestration. Ecosystems with abundant seagrass beds experience a clear water column which allows for abundant light penetration and the consequent establishment and survival of photosynthetic organisms, providing suitable habitat for a number of species that interact through complex food webs. For this reason seagrasses affect humans by favoring fish and shell production. Despite their importance, seagrasses are in decline globally due to climate change drivers and rapid rise of human populations on coastal regions. Conservation researchers strive to understand seagrass dynamics to help with preservation, restoration and other conservation strategies that are in place to help protect reduce and possibly stop seagrass declines.
In this thesis, I carried out an assessment of depth limits of seagrasses in the Chincoteague Bay, in the eastern shore of the United States. The results show seagrass in Chincoteague to occur at depth ranges of 0.2-1.2m, which are shallower than expected. The results also suggest that about 79 percent of the bay is suitable for seagrass restoration based on depth, though other factors are expected to play a role in determining the habitat suitability for seagrasses. These results could help future suitability studies that consider other factors affecting seagrass establishment and survival in shallow coastal bays.