Abstract:
Oregon English sole catch data from 0 to 80 fathoms between Coos
Bay and Cape Lookout were examined for the years 1973, 1975, and 1976.
English sole is a major target species of this inshore trawl fishery.
Comparison of depths of maximal values of catch per unit effort, effort,
and total English sole landings for each month was used to determine
when effort in this mixed-species fishery was directed on English sole.
Petrale sole, normally a deeper water species, move inshore during late
spring and summer months and may be a primary target during this season.
Dover sole appeared to be a target species during certain spring months
but rarely overshadowed either English or petrale sole catches. External
factors such as weather conditions and market variability affected total
monthly effort levels and were included in an interpretation of seasonal
abundance and migration trends of English sole.
Longshore movements were largely obscured by the month-to-month
fluctuations of effort from Newport and Coos Bay, the two major fishing
ports within the defined landing area. The Newport fleet is somewhat
larger, but variable weather conditions may result in greater effort on
the part of the Coos Bay fleet during certain months. Seasonal inshore-off
shore movements of English sole, however, were consistently evident
for the three years. Average depths of capture and catch per effort increased
during fall and early winter months suggesting movement into
deep water. Examination of ovary condition of English sole caught in
the vicinity of Heceta and Stonewall Banks off the central Oregon coast
linked this concentration and offshore movement to spawning. Inshore
movement and decreased landings in the spring suggested a post-spawning
dispersal.
