554 
Fishery Bulletin 95(3), 1997 
& & & 
Top oblique view 
Side view 
Hoop 
Figure 2 
Diagrams of the bycatch reduction devices used in this study: (A) Authement- 
Ledet excluder; (B) Lake Arthur excluder; (C) Cameron shooter; and (D) Eymard 
accelerator. 
organized. The industry commit- 
tee members recommended basic 
trawl specifications and sampling 
areas. BRD’s were selected from 
a pool of 14 industry- and NMFS- 
developed BRD and turtle ex- 
cluder device (TED) designs sug- 
gested by members of the com- 
mittee. Four industry-developed 
BRD designs were selected: Au- 
thement-Ledet excluder, Lake 
Arthur excluder, Cameron shooter, 
and Eymard accelerator (Fig. 2). 
The Cameron shooter, and very 
similar designs, such as the 
fisheye and Florida fish exclud- 
ers, have had the widest use 
among commercial shrimpers 
along the U.S. Gulf of Mexico and 
Atlantic coasts. The other devices 
have been used on a limited ba- 
sis in inshore and offshore waters 
of Louisiana, primarily in certain 
management zones: Eymard 
(zone 1), Authement-Ledet (zone 
2), and Lake Arthur (zone 3). 
Seven identical four-seam, ny- 
lon semiballoon trawls with 6.1-m 
headrope length were construct- 
ed; three were used as control 
nets and four were randomly se- 
lected for BRD installation. Each 
net had 3.5-cm stretch mesh in 
the body (no. 7 twine) and in the 
codend (no. 15 twine). 
The Authement-Ledet excluder 
(Fig. 2A), constructed of 3.5-cm 
stretch mesh polyethylene web- 
bing, was 35 meshes long and 
contained an inclined plane that 
was angled 20° from the net bot- 
tom to guide the catch upwards. 
The inclined plane was 18 meshes 
wide at the front and 30 meshes 
wide at the back; the back of the 
inclined plane was attached 18 
meshes from the top seam of the 
trawl net. Fishes swimming for- 
ward from the codend were guided 
by the inclined plane to exit 
through the 18-mesh-wide, 40- 
mesh-long bottom opening. 
The Lake Arthur excluder (Fig. 
2B) was constructed by cutting 22 
meshes across the top of the trawl 
