Skimmer Trawl Modifications to Reduce Bycatch in the Inshore Brown and Pink Shrimp Fishery in North Carolina

Abstract

A study was conducted during May-June 1995 comparing catch composition of a standard high profile skimmer trawl net (12 fi) and a low profile skimmer trawl net (3 fi) in the North and Newport Rivers, North Carolina. Each gear type was alternately rigged on the port and starboard sides of a commercial shrimping vessel and the catch was sampled according to criteria established by the Southeast Area Monitoring and Assessment Program The objective of the study was to determine if modifying skimmer trawl nets’ by decreasing the vertical height of the net would lower bycatch rates, yet maintain shrimp catch. Total shrimp catch in the low profile net was significantly lower than that in the control net (-32.9%, p = 0.0001), and significantly lower for brown shrimp (Penaeus aziecus) by -39.1% (p = 0.0001), but pink shrimp(P. duorarum) catches were not significantly different (-17.1%, p 0.1934). In the sample, weight of finfish biomass to total catch biomass excluding debris was similar (47.5% finfish in the low profile net and 44.8% finfish in the high profile net). The low profile net was not effective in reduction of bycatch under most conditions. Because of increased catch rates of brown shrimp by the high profile net, results suggest that shrimpers may find it advantageous to utilize a high profile skimmer net during the brown and pink shrimp seasons, rather than a low profile net. Also, the low profile net may be advantageous to fishermen under conditions of: (1) high wind, (2) shrimping in areas where tight turns are mandated, (3) presence of large amounts of floating debris, and (4) shallow water.