Rudershausen et al A comparison between circle hook and J hook performance in the troll fisheries off North Carolina 
173 
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Circle J Circle J 
Hook type 
Recreational 
Figure 9 
Plots of the average proportion of fish retained (±standard error) on circle hooks (open 
bars) and J hooks (gray bars). Data for each group are from both directed and nondirected 
trips for that species. Plots are broken down by user group (recreational [left column, 
panels A-C] and charter [right column, panels D-F[) and taxa (dolphinfish Coryphaena 
hippurus [A, D], tunas [B, E], and mackerels [C, FI). The tuna group included yellowfin 
tuna ( Thunnus albacares ), blackfin tuna ( Thunnus atlanticus ), skipjack tuna ( Euthyn - 
nus pelamis), and false albacore ( Euthynnus alletteratus). The mackerel group included 
wahoo (Acanthocybium solandri), king mackerel ( Scomberomorus cavalla), and Spanish 
mackerel ( Scomberomorus maculatus). The legend denoting fill pattern for each leader 
type applies to all panels. No bar for a particular hook-type+taxon+user-group+leader- 
type combination indicates no catch. 
catch efficiency. There are likely untested techniques 
that allow fishermen to catch non-billfish with circle 
hooks more efficiently than we found in this study. 
Cooke and Suski (2004) report that the choice of circle 
hook size is an important consideration in order to 
maximize their effectiveness. Hook size seems to be an 
especially important consideration in a mixed-species 
and mixed-size fishery such as the one we examined. 
Hook choice (size and style) was a central topic in the 
workshop we convened; in targeting each of the main 
species (dolphinfish, yellowfin tuna, and wahoo), we 
selected hook sizes and styles recommended by expe- 
rienced offshore fishermen. 
It is likely that fishermen would be more inclined 
to experiment with circle hooks and novel rigging 
strategies if they knew there would be a pending re- 
