Four species of intertidal clams; butter, littleneck,
manila, and razor clams, comprise the major portion of
landings in commercial and recreational clam fisheries in
British Columbia (BC). Initially, the targeted species was
butter clams, which were harvested for canning at various
processing facilities along the coast. Since 1971, however,
strong markets and higher prices have focused the clam
fishery on littleneck and manila clams, which are more
acceptable on the market as fresh product.
and littleneck clams retain paralytic shellfish toxins (PSP)
for a much shorter period than butter clams, adding to their
appeal as a fresh product. A few other species, such as the
varnish and razor clams, occasionally enter the commercial
clam fishery and are utilized to a somewhat greater extent
in the recreational fishery.
The clam species important to the various fisheries in B.C. include:
There are two types of commercial fisheries for
Stock assessment activities relating to commercial
fisheries for intertidal clams include:
- Collaborative survey design, sample processing and
analyses for the aboriginal communal commercial and
depuration fisheries. Results of which are reported to
- Clam collection during stock assessment surveys to
identified species, number and weight, including legal
and sublegal sized clams where appropriate. From these
data, abundance and biomass estimates are determined
from which harvest quotas can be generated.
- Retention of biological samples from surveys to
collect individual length, weight and age information in
order to develop an understanding about the status of
populations on particular beaches and growth patterns.
- Surveying beaches that are going to be harvested, as
well as several unharvested beaches to gain a better
understanding about wild recruitment processes.
- Provide data support services to Industry and First
Nations groups including: confirming survey data
quality, inputting data into an electronic format,
selecting biological samples, providing sampling
advice/training, confirming biomass estimates, and
approving sampling designs.
- Inputting all clam survey data collected by the
Depuration fishery into the DFO's main database.