Molluscan Shellfish Culture in the US: Innovation, Economy, and Environment

Feeding the Nation: the Aquaculture Alternative- CHOW 05

Richard Langan, Ph.D. University of New Hampshire

Presentation Outline

• What is shellfish aquaculture?

• Where is it taking place?

• Shellfish culture and the environment

• U.S. Industry Characteristics

• Species and methods

• Economic Impact and trends

• Factors limiting industry growth

• Prospects for the future

Shellfish Culture……

• Controlled production of bivalve molluscs

Clams, oysters, mussels, scallops

Wide variety of species and culture methods

• Filter feeders… feed on naturally occurring microscopic plant cells

• Production requires no fertilizers, feeds, drugs, chemicals or antibiotics

• More than 100 years of history in the U.S.

• Land based hatchery and nursery

• Growout in estuarine and protected and exposed* marine environments

• Applied science and innovation

Production takes place in all coastal states

Shellfish Culture and the Environment

Documented Environmental Benefits

No external Feed Source

Improves Water Clarity

Provides Valuable Habitat

Removes Nitrogen

Improves Oxygen Conditions

Ecosystem Management Tool

Improves restoration success

Mitigate the Impacts of

eutrophication

Pollution credit trading

Integrated Aquaculture

Finfish + Bivalves = Integrated Aquaculture

Uneaten food

3-10%

Fish feces

10-25%

Feed Addition

Dissolved Nitrogen (NH4)

Metabolism

65-87%

Decomposition and Remineralization

Increased Primary Production

Bivalve Culture and Removal via Harvest

Denitrification

U.S. Industry Characteristics

• Highly Diverse

• Individuals to larger companies

• Several acres to hundreds of acres

• Discrete Sector to Vertically Integrated

• Low Tech to High Tech

• Niche products to commodity

• Innovation in production methods

• Alternative for commercial fishermen

• Applied science in action

Shellfish Species and Culture Methods

• Oysters

Eastern, Olympia, Belon, Pacific, Kumomoto, Asian

• Clams

Quahog, Manilla,

Goeduck, Softshell

• Mussels

Blue and Mediterranean

• Scallops

Bay, pink and sea

Culture Stages

• Larval stage production

Natural production

Hatchery maintained broodstock

• Nursery culture

Land based, in-water, upwellers

• Seed production

Natural settlement, hatchery production, remote setting

• Growout

Extensive, intensive

Oyster Culture- East, West and Gulf Coasts

• Larval Supply

Natural- NJ, CT, LA

Hatchery- E &W coasts

• Seed Production

Natural Settlement

Hatchery Production

Single seed, clusters

Oyster Culture (cont’d)

• Nursery

Upwellers, Bagged shell with attached seed

•Growout

On Bottom

Containment and suspension

Clam Culture-East and West Coasts

• Hatchery production of larvae and seed

• Upwellers for nursery culture

• Growout on bottom with predator netting

Mussel Culture - Northeast and Northwest

• Larval and Seed Supply

West- Hatchery

East- natural production

• Growout

Bottom culture

Ropes or sleves suspended from rafts,

surface longlines, and submerged longlines

Submerged Longlines - open ocean opportunities

http:// ooa.unh.edu

Scallop Culture

Larval and seed production

Hatchery techniques well developed for bay scallop

Growout- Experimental

Containment in cages and nets

Bottom Culture

Restoration and enhancement (bay scallops)

Sea scallop culture relies on wild caught seed

Economic Impacts and Trends

Farm Gate Value (2003) Trend Imports

All species $160 M $130 M

Oysters $100 M $14 M

Clams $ 56 M $38 M

Mussels $ 4 M $45 M

Scallops $ N/A $33 M*

Employment > 10,000

Limiting Factors to Industry Growth

• Coastal Pollution

• Competing Uses (incl. viewscapes)

• Disease

• Harmful Algal Blooms

• Biofouling (incl invasives)

• Predation

Prospects for the Future

• OpportunityDemand is high and continues to rise

Inshore and offshore site availability

Component of Integrated Coastal Management• Motivation

EconomyEnvironmentFood security

• NeedsSocial AcceptanceInvestment $$Gov’t supported R&D

Thank You!