NOAA Marine Aquaculture Program, Alternative Shellfish Production Methods: Environmental Interactions and Regulatory Compliance

Purpose or Scope:

This research continues the environmental and technical assessment of alternative methods to cultivate bivalve shellfish, and the development specific guidance for modifications and improvements in those methods. It focuses on economically important alternative shellfish production practices which are not addressed by existing or past research projects on either coast of the U.S., but have been subject to increasingly critical environmental and regulatory oversight. These include cage and bag-on-bottom, bag-on-rack, suspended, and longline oyster and clam culture, and net-protected or enhanced clam culture methods. The research is conducted in collaboration with representatives of the East and West Coast shellfish industries and is intended to meet the goals and objectives of the NOAA program. The goal of this project is to provide the industry with the information and tools to move forward proactively in achieving the regulatory compliance needed to assure it can continue to operate sustainably and viably far into the future. The findings will be relevant in addressing local problems and issues; and the study results will be pertinent anywhere in the U.S.

Approach:

The general research approach is as follows: 1) Complete and expand the analyses and interpretation of data on habitat and community characteristics within and adjacent to alternative shellfish aquaculture and control sites; 2) Examine the utilization and habitat responses of resident fish in EFH and ESA listed species in shellfish growout areas; 3) Determine sediment and water column interactions associated with culture methods and compare with control conditions; 4) Quantify seasonal patterns of nutrient sequestering by macroalgae associated with commercial shellfish growout; and 5) Develop recommendations for modifications to growing methods to reduce adverse and maximize positive environmental effects and improve production efficiency and yield in an ecologically-sound and economically-viable manner; and disseminate relevant research to researchers, growers and environmental managers.

Progress and Results:

The following research activities were conducted (through fall-2007):

Community and habitat research. We continued analyses of existing data for the Puget Sound and Connecticut sites, conduct additional sampling to characterize sediments in Puget Sound and Humboldt Bay, and conducted seasonal epibenthic sampling and analysis in Humboldt Bay. Approximately 1/2 of the remaining samples from Puget Sound were analyzed, and data analyses and reporting from Connecticut were completed. Benthic sampling and placement of sediment traps in Humboldt Bay was completed in late May 07, and with a follow-up sampling event in late August 2007.

EFH/ESA fisheries analysis. Fish use of shellfish culture habitats was determined by targeting resident and migratory species. Non-destructive video methods were successfully deployed at several Puget Sound and Willapa Bay sites during early fall 2006 and late spring 2007. This work was continued through the summer and fall period 2007. Additional work was begun by late summer 2007 in Humboldt Bay using traditional sampling methods in Humboldt Bay. In addition, summer 2007 fish sampling data from USDA and locally sponsored field studies in Willapa Bay, WA are also being incorporated into the data analyses.

Sediment and water column affects. This task extended previous studies of water movement through culture units to assess sediment transport. Sediment traps were placed in Humboldt Bay and two locations in Puget Sound during the May-July 2007 period. The project team (see photo below) coordinated a field program during the August-September 2007 period to complete water column and shellfish feeding studies at Thorndyke Bay, Hood Canal, WA. Data from these studies are being entered into three-dimensional computer models to study flow patterns through the different types of culture systems. The resulting computer models will be used to simulate the transport, erosion, and/or deposition of sediments around the shellfish culture systems in a combination of tidal and wind-driven wave conditions.

Nutrient retention in macroalgae. This task was designed to capture nutrient trading credits or other economic returns for the industry identified. All work proposed for this task will be conducted during the August to October 2007 period.

Present recommendations and guidance for alternative shellfish culture practices. Our outreach/education specialist, Tessa Getchis, participated in a site visit of shellfish hatcheries, nurseries and grow-out operations in Washington State. Getchis met with several aquaculture producers to discuss their concerns regarding shellfish aquaculture and the environment, and in particular increased negative public perception and media attention towards the industry. Getchis also met with Daniel Cheney (Pacific Shellfish Institute) and Steven Landino (NOAA National Marine Fisheries Service) to discuss the impacts of shellfish aquaculture on the east and west coasts of the U.S. The meeting participants discussed the environmental as well as social concerns of producers, regulators, policy-makers and coastal land-owners. The bulk of remaining activities are scheduled for completion in 2008. The principal future work elements are presentation of the results to farmers and resource managers, and development of manuscripts for peer review. In addition, work activities include maintenance of a comprehensive online database on shellfish aquaculture and the environment.

Presentations about project results are being made at regional meetings. The presentations listed below can be viewed in PDF format (file sizes are indicated).

Project Partners:

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