Biodiversity

Seagrass meadows provide important ecosystem services, including supporting diverse faunal communities by providing habitat, food, and shelter. The size, shape, and patchiness of the seagrass landscape, and the ways that animals experience this landscape through dispersal and movement, are important to mediating biodiversity.We study how the state changes from bare sediment to seagrass meadows, structures biodiversity and the dynamics of valuable fish and shellfish. We also point to work done by our colleagues at the Virginia Institute of Marine Sciences on faunal communities within these environments.

Key Findings

Seagrass restoration leads to increased faunal abundance and diversity

• In a 7-year study, summer fish abundance was 4.6 times higher in seagrass meadows relative to nearby unvegetated areas; likewise, seagrass restoration more than doubled fish species richness (Hardison and Castorani, in prep.)

• Adult blue crabs are more numerous in areas of sparse seagrass than dense seagrass(Cheng and Castorani, in prep.)

• Stable isotope (carbon, nitrogen, sulfur) analysis indicates the importance of seagrass detritus to fish inhabiting restored meadows, with a few species showing evidence of live seagrass consumption based on fatty acid markers(Harbeson 2010)

• Inthe restored meadows, seston was a main organic matter source for fish consumers in addition to seagrass detritus; in nearby bare areas, seston and macroalgae were the primary sources (Harbeson 2010)

• Epifaunal invertebrate biodiversity (richness, evenness, functional diversity) were higher in a restored seagrass meadow relative to a reference site with poorer water quality (Lefcheck et al. 2017)

 • Biomass of epifaunal invertebrates has increased with the increase and cover of seagrass; biomass per unit area stabilized within 2–4 years of restoration(Orth et al. in review)

Related Publications

Harbeson, S. 2010. An investigation of nutrient transfer in a restored eelgrass, Zostera marina, meadow. Ph.D. Dissertation, University of Virginia, Charlottesville, VA
 
Lefcheck, J. S., S. R. Marion, and R. J. Orth. 2017. Restored eelgrass (Zostera marina L. as a refuge for epifaunal biodiversity in mid-Western Atlantic coastal bays.  Estuaries and Coasts 40:200–212
DOI 10.1007/s12237-016-0141-x