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Fishery Bulletin 101(3) 



both tongue trawls and flat trawls were sampled in August 

 through October. Tongue trawls are modified mongoose 

 trawls that have a higher vertical profile for catching 

 white shrimp. In addition, the tongue trawls had a greater 

 headrope length than the flat trawls; therefore many of the 

 fishermen switched from pulling two flat trawls to pulling 

 one larger tongue trawl. Tows typically lasted around one 

 hour The observed catch of shrimp per day in the Cape 

 Fear River was almost three times higher than the observed 

 catch of shrimp per day in Pamlico Sound (Table 3). 



Total shrimj) landings and total shrimp trips during the 

 observed months from the 1995 trip ticket database were 

 used as the expansion factors in the estimates. Over half 

 of the total .shrimp landings, or 2,018,622 kg, were caught 

 in the northern region between July and October and only 

 122,893 kg came from the southern region between August 



and October, the months that corresponded to the observa- 

 tions. Although there were about twice the number of trips 

 and days fished the northern region, the average catch per 

 trip (kg/trip) from the northern region was almost nine 

 times higher than the catch per trip from the southern 

 region (Table 3). 



The different estimation methods made a tremendous 

 difference in the estimates of bycatch, but the differences 

 were exactly opposite in the two geographic regions and 

 varied somewhat by species. Total bycatch estimates de- 

 rived with the basic F:S ratio estimator (mean of the ratios) 

 by both weight and number were two to seven times higher 

 than those based on the CPUE-mean-per-unit method for 

 all species in the northern region, and about two to five 

 times lower by both weight and number for all species in 

 the southern region (Table 4). For Atlantic croaker and 



