Science Serving Maryland's Coasts

R/SV-AQ-5

Effects of Oyster Aquaculture on Submersed Aquatic Vegetation (SAV) Habitat

Principal Investigator: 

Cassie Gurbisz

Start/End Year: 

2020 to 2022

Institution: 

St. Mary's College of Maryland

Co-Principal investigator: 

Jeremy Testa, University of Maryland Center for Environmental Science, Chesapeake Biological Laboratory; Dong Liang, University of Maryland Center for Environmental Science, Chesapeake Biological Laboratory

Strategic focus area: 

Healthy coastal ecosystems

Description: 

As Chesapeake Bay (CB) submersed aquatic vegetation (SAV) recover and oyster aquaculture operations in Maryland expand, the potential for these important shallow-water resources to spatially overlap and come into conflict is increasing. Until recently, the Code of Maryland Regulations has restricted installation of aquaculture gear in areas occupied by SAV and further requires that aquaculture operations cease if SAV expands into an existing lease. These regulations were intended to support SAV restoration under the assumption that aquaculture will impair SAV growth. However, the extent to which aquaculture is detrimental to SAV growth and the mechanisms by which it impacts SAV habitat are poorly understood at present. The Maryland governor has recently approved new legislation that grants the Maryland Department of Natural Resources flexibility in permitting usage of water column equipment in leases containing SAV. This new legislation will end in 2024, at which time the effects of aquaculture on SAV will be reevaluated. Thus, there is now a critical need for quantitative information on SAV-aquaculture interactions to guide both evaluation of current SAV-aquaculture conflicts and policy reevaluation after five years. Our proposed research aims to 1) determine regional differences in the probability of conflict between SAV growth and aquaculture, 2) assess whether existing aquaculture operations have already affected SAV growth and distribution, and 3) quantify how much and by what mechanisms aquaculture modifies SAV habitat. We propose a two-phase research plan that combines a retrospective data analysis of environmental conditions, remotely sensed SAV distribution, and aquaculture location data with an observational field program to address these objectives. Our broad goal is to generate scientifically defensible information that can guide policy and management activities that impact Chesapeake Bay restoration and the oyster aquaculture industry.