Íslenskar landbúnaðarrannsóknir - 01.09.1978, Side 43

FISHERY STATISTICS 41
TABLE 1. Arrays wich constitute the secondary file.
Array Name Meaning
MDAYS (NDF, K.IND) MWATE (NW, KIND) KWT (KIND, MSEX) NRW (KIND, MSEX) KOUNT (MSEX, KIND, MBAIT) .. . . .Number of fish by day (NDF) and by species (KIND) .Number of fish by weight class (NW) and species (KIND) .Total weight recorded by species (KIND) and sex (MSEX) .Number of fish with weight records by species (KIND) and sex (MSEX) .Number of fish caught by sex (MSEX), species (KIND) and bait (MBAIT)
With the formation of the Institute of
Freshwater Fisheries in 1946, a systematic
recording of catches by rivers com-
menced. A logbook (Veiðibók) was de-
veloped and has been in use since, with
subsequent changes and improvements.
The logbook contains information on each
fish captured, date and place, fisherman,
species, length (to the nearest centimeter),
and weight (in pounds equal to 500
grams). Usually the type of bait used is
listed, as well as weather at the time of
fishing.
From 1946 to 1973, under the direction
of Einar Hannesson, the catch data were
processed manually to produce weekly
total catch figures by rivers, weight dis-
tribution, and average weight by species
and sex.
The computerized bookkeeping of
catch and effort, initiated in 1974, gives
the advantage of speed and accuracy;
thus, the amount of information to be de-
rived from the catch books is increased.
Under the present program, each river
can be processed in sections and then
combined; or many rivers can be proces-
sed together to procuce individual or
combined outputs.
Various observations wich are not be-
ing presently used in the program are,
nevertheless, incorporated into the data
file for possible later use (e. g., length of
the fish, rods fished per day). Others, such
as place of capture within the river, or
enviromental factors, can easily be added.
The number of gillnets fished for sal-
mon decreased over the years, as more
rivers were fished exclusively by rod. At
the present time only three glacial rivers
are still fished by gillnets. The records
from this fishery are not incorporated into
the data file described here; however, the
program provides options whereby this
can be done eventually.
Finally, the data file can easily be used
as a data base for future programs of
statistical analysis, stock estimation and
many other applications.
PRESENT DATA FILE
Input.
The basic input is the logbook wich was
redesigned in 1974 to permit computer
data entry personnel to work directly from
its pages (Fig. 1). The new design retained
much the same format as the old logbook
so that users would not be confused by the
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