GRANT
NUMBER:
NA66FD0041
NMFS NUMBER: 95-AKR-051
REPORT
TITLE:
Flatfish Size Separation in Trawl Gear: Technique to Increase
By-Catch Reduction and Under-Utilized Species Development
AUTHOR: C.
G. Bublitz
PUBLISH
DATE:
1998
AVAILABLE
FROM:
National Marine Fisheries Service, Alaska Region, P.O.
Box 21668, Juneau, AK 99802-1668. TELEPHONE:
(907) 586-7280
ABSTRACT

The goals and
objectives of this project were to evaluate the use of
separator panels as a technique to reduce the capture
of small flatfish. Two separator panels were placed one
and two meters above the belly of the net just aft of
the footrope with each separator panel leading to a codend.
The catch from each separator panel codend and the main
codend were sampled for species composition and length
frequency. Results indicate that species specific vertical
and horizontal size separation occurs during capture.
The purpose of this project was to initiate work on the
use of separator panels as a technique to reduce by-catch
in flatfish fisheries. The overall goals of this project
were to determine the applicability of separator panels
in reducing undersized flatfish discards, separating flatfish
species, and improving halibut release in direct cod trawl
fisheries. Particular items to be addressed were to evaluate
rock sole size separation and separation of arrowtooth
flounder and Pacific halibut. The specific objectives
which were addressed to accomplish this goal were: (1)
modify a commercial groundfish trawl by incorporating
two separator panels attached to individual codends; (2)
determine total catch, species composition, length frequency,
and rock sole sex ratios; and (3) evaluate escape and
retention by species in each separator panel and the main
codend.