[1]During 1963-1984, BMV oval doors were used in spring and autumn surveys;
since 1985, Portuguese polyvalent doors have been used in both surveys.Adjustments
have been made to the 1963-1984 catch per tow data to standardize these
data to polyvalent door equivalents. Conversion coefficients of 1.56
(numbers) and 1.62 (weight) were usedin this standardization (NEFC 1991). [2]Spring surveys during 1980-1982, 1989-1991 and 1994 and autumn
surveys during 1977-1981,1989-1991,and1993 were accomplished with the R/V
Delaware II; in all other years, the surveys were accomplished
using the R/V Albatross IV.Adjustments have been made to the R/V
Delaware II catch per tow data to standardize these to R/V
Albatross IV equivalents. Conversion coefficients of 0.79 (numbers)
and 0.67 (weight) were used in this standardization (NEFC 1991).
[3]Spring surveys during 1973-1981 were accomplished with a '41 Yankee'
trawl; in all other years,spring surveys were accomplished with a '36
Yankee' trawl.No adjustments have been made to the catch per tow data
for these gear differences. |