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study sites were located in Cowichan Bay,
on Vancouver Island, British-Columbia (Figure
1). Samples were collected and
analyzed in August of 1997. The first
site, just off the Westcan dock, was
chosen because of its proximity to the
log handling. The corrected depth at
which the sample was taken was 20m. The
second site, 600 m away, was chosen for
being at a similar depth, but away from
the industry site.The samples were
collected by using a Ponar grab which was
lowered on a vertical warp from a boat.
Once raised, the contents of the grab
were emptied into a flat bottomed bin.
Subsequent crude substrate analysis was
conducted using a one liter measuring
cup, three graded sieves, and a graduated
Imhoff Cone. Salinity of the water at
both sites was determined by use of a
refractometer. Water samples at 20 meters
were obtained using a Van Dorn water
sampler while surface samples were
collected with a graduated cylinder. Crude benthos
analysis was conducted using a sample
dish, a receiving dish, forceps, and a
compound microscope of 10X magnification.
Animals were separated in the receiving
dishes into the following categories;
segmented worms (phylum Annelida),
clams (class Bivalvia), snails
(class Gastropoda), brittle
stars (class Ophiuroidea), and
other. When possible, and with the
assistance of Dr. Austin, further
identification was made. Species
differentiation was based solely on
visual assessment of morphological
differences, and although specific
species name was not always determined,
species number was tentatively
established. The numbers of animals per
square meter was extrapolated by
multiplying the numbers of animals by
twenty. Both samples were also compared
to previous data obtained by students in
Dr. Austin's science camps on July 15,
1997 (site 1) and on Aug. 8, 1997
(site2). Interpretation of the research
data also included calculations of
Margalef's diversity index.
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