Restoring Nanaimo’s Shellfish Beds

For thousands of years, the people of Vancouver Island’s Snuneymux^w First Nation relied on fresh seafood from Nanaimo Harbour as a dietary staple and for ceremonial and other traditional purposes. Since 1949, however, the harvesting of shellfish in the harbour has been prohibited due to bacteriological and chemical contamination from forestry, agricultural, industrial and commercial activities along the coastline and upstream on the Nanaimo River.

Despite the fact that it is illegal, some band members have continued harvesting shellfish for their own uses or subsequent sale to other consumers. With single catches of up to 200 kilograms of shellfish possible on a good tide, the potential impact of such activities on the health of First Nations and other consumers is a serious concern. To address the situation, shellfish and aquaculture experts at Environment Canada are working with the Snuneymux^w people and the British Columbia Ministry of the Environment, Lands and Parks to restore water quality in Nanaimo Harbour and reopen its shellfish beds to legal harvesting.

As a key player in the Canadian Shellfish Sanitation Program, Environment Canada is responsible for surveying and classifying the nation’s coastal waters to ensure that the waters from which bivalve molluscs such as clams, oysters, mussels and certain species of scallops are harvested, are of acceptable sanitary quality. These filter feeders take in water through their gills and strain out minute particles of food for consumption. As a result, contaminants become concentrated in their tissue and can cause serious illness and disease in those who consume them.

To help determine the sanitary quality of these shellfish-overlying waters, biologists in Environment Canada’s Pacific and Yukon Region take approximately 5 000 samples per year and analyze them for fecal coliform bacteria. They also carry out toxicity testing and shoreline assessments to determine if chemical contamination is a concern. Based on their findings, growing waters are classified as approved for direct harvesting, closed (meaning harvesting may take place only under certain conditions and with a special permit), or prohibited completely.

Of the 140 coastal sectors in the region—which encompass 28 000 kilometres of coastline from the border of Alaska to the 49th parallel, from the mainland coast to the west coast of Vancouver Island and the Queen Charlotte Islands—less than 10 per cent are classified as prohibited. Most of these are major harbours, such as Nanaimo, Comox, Victoria, Esquimalt, and Vancouver. A significant amount of pollution in Nanaimo Harbour is fecal contamination that washes off the land as a result of rainfall. However, high levels of chlorinated compounds are found near mills at one end of the harbour, and the waters also receive pollutants that originate upstream of the Nanaimo River estuary.

In 1999, the Department entered into a three-year agreement under the Georgia Basin Ecosystem Initiative to work with the First Nations to identify the sources and extent of contamination in Nanaimo Harbour and determine ways to upgrade the classification of the beds. The first phase of the project is aimed at improving water quality in the eastern half of the harbour sufficiently that depuration harvesting will be allowed with a special permit. Depuration is a purification process in which harvested shellfish are put into large holding tanks on land, and cleanse their systems through prolonged contact with continuously flowing clean seawater. If shellfish harvesting in the harbour were reopened, it could represent a million-dollar-a-year industry for the Snuneymux^w First Nations.

Since having been formally trained to monitor water quality in the harbour, the Snuneymux^w have carried out extensive water-quality sampling and shoreline assessments, and mapped their findings on computer. If the agreement is extended, more tests will be conducted to determine bacteriological levels during the wet season, when runoff is at its peak. Biologists are also advising their First Nations partners on how to approach organizations whose activities have been identified as sources of pollution and encourage them to clean up their operations.

This initiative will be given significant exposure at the International Conference on Shellfish Restoration, which will take place in Nanaimo in September 2001. The conference will focus on the theme of using science and community partnership to improve the health of coastal ecosystems through shellfish restoration.

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