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Commercial Fishery Data
& Maps
Commercial Catch Data
Catch data (landings) from commercial shellfish fisheries obtained from
DFO are reported by fisheries management area and subarea. For catch
reporting, the Haida
Gwaii/QCI area includes Areas 1, 2 (2E & 2W), 101,
102, 130 and 142. Each area is composed of varying numbers of subareas.
Data can be reported for any individual subarea or area where more than
3 boats fished within that reporting area and time period. If there are
less than 3 boats fishing within any given reporting area and period,
the catch data is withheld due to DFO confidentiality guidelines.
Additional data points for some fisheries were also obtained from DFO
Pacific Stock Assessment Review Committee (PSARC) reports.
Commercial Supply Maps
The commercial fishery supply maps by DFO management subarea were
produced using DFO catch data summaries, in addition to PSARC report
data for some fisheries. It is important to
note that these subarea boundaries do NOT correspond to actual fishing
locations associated with each fishery, which are more localized than
the subareas shown. To better represent the
extent of shallow water (less than 20 metres or 60 feet depth)
fisheries, the subareas were clipped at the wider of 1 km from shore or
the 20 metre depth contour.
To allow comparison of the relative contribution
of each subarea to the Haida Gwaii/QCI fishery each year, the data were
analysed as follows.
For each yearly supply map:
- Catch by subarea resolution was obtained for
the all areas possible;
- Percentage contribution of each subarea (to
the total annual catch reported over all the subareas possible) was
calculated;
- Subareas were ranked from highest to lowest
percent contribution for the year;
- Subareas were ranked HIGH, MEDIUM and LOW
commercial supply value based on this ranking and the cumulative
percentage of catch these subareas supplied to the commercial fishery.
In this way, the subareas that contributed the most catch to a fishery
in any given year was assigned a HIGH supply value, and those that
contributed least to a fishery were assigned a LOW value;
- HIGH commercial supply value (red) was
assigned to those subareas that made up the highest (first) 40% or more
of the catch;
- MODERATE commercial supply value (orange) made
up the next 40% of the catch (to a cumulative percent value of 80% or
more);
- LOW commercial supply value (yellow) made up
the last 20% of the annual catch (to a cumulative percentage of 100%);
- UNDISCLOSED commercial supply value (purple)
was assigned to all other subarea polygons where landings had been
reported but where catch data was withheld for confidentiality reasons;
- The commercial catch graph accompanying each
yearly catch map shows the actual values attributed to the HIGH,
MEDIUM, LOW and UNDISCLOSED supply categories for that year. A larger
downloadable catch graph that shows the catch distribution in more
detail is available for each species.
For summary maps showing all years
of data combined:
- Catch by subarea resolution by year for all
areas possible was totaled to generate a summary of total catch over
all years for each subarea with reported catch;
- Percentage contribution of each subarea to the
total reported catch, ranking and supply categories were determined
using the same analysis as done to produce the yearly supply maps.
- Note that because of this analysis method, the
accompanying graph showing yearly catch over the given time period is
not a direct reflection of the amount of catch in each supply category
in the ‘all years’ map. In addition, the
UNDISCLOSED supply areas do not show in the ‘all
years’ map because landings were reported at least once in
each subarea within the ‘all years’ time period.
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