Shellfish Farming

Intensive fencing on shellfish farms may change the intertidal zone and impede fish passage

Shellfish cultivation has a long history in British Columbia, including the use of ancient clam gardens in the Broughton Archipelago (near the north end of Vancouver Island).   The last hundred years have seen a dramatic increase in the scale and intensity of commercial shellfish operations along Canada’s West Coast.

Today, nearly 500 coastal sites are leased for commercial shellfish farming in B.C. These sites are operated by 314 different companies, cover 3,200 hectares and produce 9,400 tonnes of food (2006 data).  This is no longer a small local industry. – in the words of an industry promoter – agribusiness.  In Washington State and on the East Coast of Canada it represents a significantly larger business.

The primary species grown in B.C. are oysters, clams and scallops.  More recently, geoduck farming has been introduced.  There are two basic types of shellfish farming:
•    one involves suspending the organisms from rafts or buoys.
•    the second involves growing the organisms on or near the seabed in intertidal areas near shore (intertidal zones are the aquatic areas exposed to the air at low tide and submerged at high tide).

There are environmental concerns about both of these types of farming. There are also concerns about the continued introduction of foreign shellfish species into our coastal waters. 

As consumer demand for seafood increases, the industry anticipates growth.  The provincial government has been encouraging the expansion of this industry for a decade, yet production has been relatively flat for several years. 

This industry maintains that their practices are safe for the environment and has made significant efforts to improve operational issues such as reducing industry debris washing up on local beaches. However, there are gaps in the independent research on ecosystem impacts.  These knowledge gaps must be filled before the industry expands.

The 2005 David Suzuki Foundation report: Sustainable Shellfish – Recommendations for sustainable aquaculture points to some of the potentially harmful effects of shellfish farming, underscores the need for rigorous regulation and monitoring, and proposes solutions for farmers and policy makers on how to develop a more sustainable industry.

Full report / Executive summary

Sustainable Shellfish outlines nine key recommendations for a sustainable shellfish industry:

1. Ensure that anti-predator netting does not impact birds or other marine life;

2. Undertake more studies on phytoplankton depletion;

3. Stop the introduction of new alien species for commercial purposes;

4. Undertake rigorous cadmium testing and research before allowing expansion of oyster farms;

5. Prevent fisheries act violations by tightening existing regulations;

6. Suspend or revoke the licenses of farmers who contravene existing regulations;

7. Apply rigorous scientific assessment before introducing new farms;

8. Prohibit further industry expansion until adequate scientific studies (including cumulative effect studies) have been completed; and,

9. Incorporate ecosystem health into all future shellfish aquaculture plans.

Take action!
If you are concerned about the lack of science and research into the effects of intensive shellfish aquaculture on the B.C. coast, contact the Honourable Stan Hagen, Minister of Agriculture and Lands at stan.hagen@leg.bc.ca

A less-intensive shellfish farm on the BC coast.