Teresa Thorpe 1 and Kenneth Sessions 2. Final Report to NC Sea Grant 06-FEG-17. Lane, Wilmington, NC

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1 CATCH POTENTIAL AND CONDITION OF SHRIMP AND BYCATCH ASSOCIATED WITH A NEW RCGL SHRIMP TRAP DESIGN, AND EVALUATION OF COMMERCIAL TRAPS IN DIFFERENT REGIONS OF SOUTHEASTERN NORTH CAROLINA Teresa Thorpe 1 and Kenneth Sessions 2 Final Report to NC Sea Grant 06-FEG-17 1 University of North Carolina-Wilmington, 5600 Masonboro Loop Road, 1 Marvin K Moss Lane, Wilmington, NC thorpet@uncw.edu 2 P.O.Box 3026, Topsail Beach, Wilmington, NC 28445

2 Table of contents Abstract iii 1 Introduction 1 2 Materials and Methods Trap Design and Set Protocol Biological and Environmental Data Data Analysis 4 3 Results I: Commercial shrimp traps Shrimp catch data Bycatch 7 4 Results II: RCGL shrimp traps Shrimp catch data Bycatch 9 5 Discussion 14 References 17 Appendix I: Dissemination of information 19 ii

3 Abstract The shrimp fishery in NC is one of the most lucrative commercial fisheries in the state with almost 6 million lbs landed in 2006 and a market value of just over US$9 million. An additional 49,365 lbs were landed by recreational fishers. The majority of the recreational fishers use otter trawls primarily in estuarine waters. A major concern associated with shrimp trawling is the level of bycatch and its impact on fish populations. An additional gear that can used to harvest shrimp recreationally is a shrimp trap. A non-baited pot that is set in shallow waters close to the banks of the Intracoastal Waterway (ICWW), traps intercept shrimp as they migrate to the ocean. Being a semi-permanent staked gear they cause minimal disturbance to the bottom. The shrimp caught are also a high quality product as they are not subject to the crushing injuries typically observed in trawl fisheries. Experimental testing of RCGL traps in the ICWW behind Topsail Beach demonstrated that they have good potential as a recreational gear. Average catch rates were 8 oz shrimp for an average set of 52 minutes with a peak catch rate of over 4 lbs shrimp/trap/hour and a modal count/lb of 35. The average finfish:shrimp ratio for RCGL traps was 0.11:1. Use of commercial traps outside of Topsail was not as successful for a number of reasons. 1) The area of experimental fishing coincided with a closure to commercial shrimp fishing for the entire 2006 season due to small sized shrimp. 2) Strong tidal currents in Brunswick County may reduce trap efficiency. 3) Extensive shallow flats in Topsail and closer proximity to inlets facilitates shrimp movement up to the banks where they are intercepted by the traps. However, in the Topsail area traps were easy to use by a team that was unfamiliar with the gear. Traps are cheap and easy to construct and a boat is not necessary making the fishery widely accessible to the general public. iii

4 1 INTRODUCTION The shrimp fishery in North Carolina (NC) is one of the most lucrative commercial fisheries in the state with almost 6 million lbs landed in 2006 and a market value of just over US$9 million (Figure 1.1). An additional 49,365 lbs were also landed by recreational fishers in Commercial landings are relatively stable averaging around 6 ½ million lbs/year with occasional low yield years (Sessions and Thorpe 2006). The majority of shrimp are harvested using otter trawls and 73 80% of commercial trips occur in estuarine waters (NC Division of Marine Fisheries [NCDMF] 2006). Shrimp trawls are non-selective and typically have a high bycatch to shrimp ratio, as much as 80% of the total catch from the US shrimp fishery is estimated to by bycatch (National Marine Fisheries Service [NMFS] 1995). In southeast NC estuarine waters juvenile fish form a large proportion of the bycatch (Coale et al. 1994; Hines and Rulifson 1999; Logothetis and McCusiton 2005; Johnson 2006). The major concern is that removal of a significant proportion of juvenile fish will have a deleterious effect on population growth rates and lead to population decline. In addition to shrimp trawl modifications that aim to reduce bycatch, efforts have also been directed at developing alternative commercial and recreational (RCGL) gears. In 2005 a Fishery Resource Grant was awarded to evaluate the efficiency of a new shrimp trap design (Sessions and Thorpe 2006). Unfortunately, experimental fishing coincided with a very poor year for shrimp that was likely due in part to an above average number of severe weather events that affected coastal NC in These events had a significant effect on environmental conditions by decreasing salinity, lowering dissolved oxygen levels as well as the physical disruption caused by wind and wave action. Shrimp are an annual stock and are most affected by environmental conditions. The January-June 2005 shrimp landings were down 75 % compared to the same period in , and by year's end 2005 had one of the lowest shrimp landings in the last 25 years at 2.3 million lbs (Figure 1.1). For this reason experimental fishing using shrimp traps was re-established for the 2006/7 season. In southeastern NC, specifically in the Topsail Sound area, shrimp traps are currently used to harvest shrimp primarily for recreational purposes. The use of shrimp traps is unique to this region where they have been used for approximately 12-years. It is a non-permanent static gear, staked out in the shallow waters of the Intracoastal Waterway and beach areas in the evening and then removed in the morning after fishing. Being a static gear there is minimal disturbance to soft-bottom habitats. Traps also have a much lower finfish bycatch rate and higher bycatch survival compared to trawls (Sessions and Thorpe 2006). The shrimp remain mobile after being 1 North Carolina Division of Marine Fisheries, personal communication

5 caught in the traps and are not subject to crushing injuries commonly seen in shrimp trawls (Troffe et al. 2003) resulting in a high quality product. Smaller unmarketable shrimp readily pass through the mesh walls of the trap and this increases the marketability of the entire catch. Although a boat was used for research purposes, a boat is not necessary making the fishery more widely available. Further, operation costs are low as material costs are inexpensive, a crew is not required to haul and process the catch, and costs associated with running and maintaining a boat may not be necessary. Given the potential benefits of shrimp traps as an alternative to trawling, an evaluation of RCGL shrimp traps by those unfamiliar with the gear was made. The application of both commercial and RCGL traps outside of the traditional Topsail Sound was also evaluated and led by a fisher experienced in using shrimp traps. Figure 1.1 North Carolina commercial annual landings of brown shrimp (Farfantepenaeus aztecus), pink shrimp (F. duorarum) and white shrimp (Litopenaeus setiferus) combined. Source: NC Division of Marine Fisheries, Trip Ticket Program. 30,000,000 25,000,000 Lbs (whole weight) Value ($) 20,000,000 15,000,000 10,000,000 5,000,

6 2 MATERIALS AND METHODS Experimental fishing was conducted in three regions of southeastern NC using commercial traps and/or RCGL traps (Figure 2.1). 1. Swansboro (Commercial) x 6 experimental trips 2. Topsail Sound (RCGL) x 25 experimental trips plus x 1 commercial experimental trip 3. Brunswick County (Commercial) x 2 experimental trips Commercial sized traps were used in the ICWW and creeks in Brunswick County and Swansboro areas. Recreational sized traps (RCGL) were used in Topsail Sound with just one trip using commercial sized traps. A total of 34 experimental trips were made from July August in 2006 and Potential fishing areas in Brunswick County and Swansboro were identified through reconnaissance trips, from trip ticket data, and from discussions with local fishers. The shrimp traps were set to coincide with a slack-flood or slack-ebb tide and soak times ranged from hours with an average of 0.52 hours. Trips were made just after sunset. 2.1 Trap design and set protocol RCGL trap rigid ⅝ inch galvanized mesh measuring 18 inches wide x 18 inches deep x 36 inches tall and sits on the bottom. Leads are 8 feet long consisting of 1 ¾ inch stretch mesh (ISM) shrimp trawl webbing with chains attached along the bottom and floats attached along the top. The total RCGL shrimp set dimension was 8 feet long with an 8 foot spread. Set distance either 50 or 100 feet apart. Commercial trap rigid ⅝ inch galvanized mesh measuring 1 ½ feet wide x 2 feet deep x 3 feet tall and sits on the bottom. Leads are 60 feet long consisting of 1 ¾ ISM shrimp trawl webbing with chains attached along the bottom and floats attached along the top. The total commercial set dimension was 60 feet long with a 60 foot spread. Set distance either 500 or 1,000 feet apart. Control trap same design as the ⅝ inch standard RCGL trap but instead made of a smaller ⅜ inch galvanized mesh. The control trap was always set at the end of the line 100 feet away from commercial traps and 50 feet away from RCGL traps. The smaller control shrimp trap was designed to determine if shrimp are in the area but not selected by the standard ⅝ inch traps. The traps had two leads extending from it, the inshore lead extended from the trap to shore and the offshore lead extended from the trap and was anchored out in deeper water (Figure 2.1.1). The maximum water depth in which the gear operated at mean high tide was approximately 5 3

7 feet. Floats were 10 oz buoyancy football floats placed every 16 inches. The gillnet webbing was also wrapped around the floats rather than threaded though the float line so that the gillnet webbing was suspended slightly above the water. This prevented shrimp from escaping over the top of the net and was particularly effective when targeting white shrimp. The shrimp traps were set outside of shrimp trawl areas and did not encroach into the navigable channel of the ICWW. Four traps were set during an experimental fishing trip, three commercial traps plus a control or three RCGL traps plus a control. The three commercial/rcgl traps were hauled twice during a trip and the control trap once resulting in seven trap hauls/trip. Traps were set alongside the bank at specific distances apart, 100 or 1,000 feet for commercial traps and 50 or 100 feet for RCGL traps. For each trap haul the time, depth, salinity and water temperature were recorded, the GPS location of the set was recorded at the control trap. 2.2 Biological and environmental data As each shrimp trap was hauled a record was made of the soak time (hours), depth at the trap (feet), salinity (ppt), and sea-surface temperature ( 0 C). Location of the fleet of traps was recorded at the control trap using GPS coordinates. The entire catch from the trap was emptied into a bucket and any bycatch (non-shrimp) was immediately removed. Bycatch was identified to species and finfish were measured (total-length [TL], mm). The release condition of all live bycatch was recorded to evaluate their likelihood of survival following a trap interaction (Table 2.2.1). The shrimp were weighed to the nearest ounce and one pound was removed with a dip-net, counted, identified to species and measured (TL, tip of the rostrum to tail, mm). This provided the average size of shrimp caught and the count per pound. 2.3 Data analysis Following tests for homogeneity of variances, t-tests were be used to detect differences in shrimp CPUE (lbs/trap/hour) by set distance. Analysis of Variance (ANOVA) or Kruskall-Wallace tests were used to determine differences in CPUE of shrimp and finfish by season, environmental conditions, and finfish to shrimp ratios by season. Post-hoc analyses were conducted using the Tukey assessment when appropriate. 4

8 Figure 2.1 Three experimental fishing locations; Brunswick County (survey area 1), Topsail Sound (survey area 2) and Swansboro (survey area 3). 5

9 Figure Commercial shrimp trap set and actively fishing. The traps were set just before A sunset with the entrance funnels facing against the flood tide. Direction of shrimp migration Direction of the tide Table ). Release condition of live bycatch caught in shrimp traps (Adapted from Hueter Condition Descriptor GOOD No gillnet damage, upon release swims rapidly down and away from the boat. FAIR No gillnet damage, swims away more slowly. POOR Upon release remains on the surface for up to 1 minute before swimming away. May show some evidence of gillnet damage. Respiration evident. DEAD Includes moribund 6

10 3 RESULTS I COMMERCIAL SHRIMP TRAPS 3.1 Shrimp catch data Nine experimental trips using commercial shrimp traps and a control trap were made in Two were made in Brunswick County (BC), six in Swansboro (S) and one test trip was made with commercial gear in Topsail Sound (TS) to see if shrimp were running and if so what size they were. The primary objective with commercial traps was to determine their applicability and ease of use in areas other than Topsail Sound. A total of 44 traps were set and hauled of which 9 were control traps. A total of 2 lbs 6 oz of shrimp were caught of which 8 oz were caught in the control trap. Brown, pink and white shrimp were caught. Catch rates were too low for count/lb determination. The shrimp total-length (TL) for all species combined ranged from mm TL in commercial traps and mm TL in the control trap. Shrimp were caught in July, August and September. 3.2 Bycatch A total of nine finfish and three non-finfish bycatch species were caught in commercial shrimp traps (Table 3.2.1). The number one ranking fish species in terms of relative abundance was the bay anchovy that represented 27.8 % of the total bycatch by number, however, catch rates were very low with a total of 18 finfish specimens caught in commercial and control traps. Of the three non-finfish species caught the blue crab ranked number one in terms of relative abundance representing 88.9 % of the total catch. Again bycatch rates were very low with 18 non-finfish bycatch specimens caught in commercial and control traps. The majority of the bycatch were retrieved alive from the traps (83.3 %). The dead specimens were three bay anchovies all caught in the control trapp. All finfish caught were juveniles based on their measured lengthfrequencies. 7

11 Table Relative abundance of all non-target species caught in commercial shrimp traps and one control trap set in Brunswick County, Topsail Sound, and Swansboro, 2006 (n=44 trap sets). Common name Scientific name Total n Total n Rank FINFISH BYCATCH (RCGL traps) (control traps) Drums (Sciaenidae) spot Leiostomus xanthurus 2 0 sand seatrout Cynoscion arenarius 1 0 Porgies (Sparidae) pinfish Lagodon rhomboides Anchovies (Engraulidae) Bay anchovy Anchoa mitchilli Herrings (Clupeidae) Atlantic menhaden Brevoortia tyrannus 2 0 Silversides (Atherinidae) Atlantic silverside Menidia menidia 1 0 Tounguefishes (Cynoglossidae) blackcheek tonguefish Symphurus plagiusa 0 1 Mojarras (Gerreidae) spotfin mojarra Eucinostomus argenteus 1 0 Spiny puffers (Diodontidae) striped burrfish Chilomycterus schoepfi 1 0 TOTAL 12 6 NON FIN-FISH BYCATCH Swimming crabs (Portunidae) blue crab Callinectes sapidus Mud crabs (Xanthidae) stone crab Menippe mercenaria Squid Atlantic brief squid Lolliguncula brevis TOTAL

12 4 RESULTS II RCGL TRAP DATA 4.1 Shrimp catch data A total of 25 experimental trips using RCGL shrimp traps and a control trap were made in Topsail Sound in 2006 and A total of 175 trap sets were made of which 25 were control traps. Just over 121 lbs of shrimp were caught in the RCGL traps and 29 lbs in the control trap (n=3,287 shrimp). The brown shrimp dominated the catch representing 82.3 % of the total shrimp catch by number. The pink shrimp represented 10.3 % and white shrimp 7.4 % of the total catch by number. Shrimp catch rates ranged from 0 4 lbs/trap/hour and was significantly higher in July compared to August and September (Figure 4.1.1). Shrimp catch rates in control traps ranged from 0 2 ½ lbs/trap/hour and was similar in July, August and September. Catch rates did not vary significantly between RCGL and control traps. The length-frequency (total-length [TL]) for all shrimp species combined ranged from mm TL in RCGL traps and mm TL in the control trap. The count/lb of shrimp species combined in RCGL traps ranged from count with a modal count of 35 (Figure 4.1.2). For control traps the count/lb ranged from with a modal count of 58. The quality of the shrimp was very good, none were retrieved dead from the traps and there was no evidence of gear related injuries. The distance between RCGL traps (50 ft or 100 ft) made no difference to the catch rate of shrimp (P = 0.971). At 50 ft distance the average catch rate was 0.66 lbs shrimp/trap/hour (± 0.97 SE) compared to 0.78 lbs shrimp/trap/hour (± SE) at 100 ft distance. When considering the catch rate by pot again there no difference in catch rates for pots that were set 50 ft apart (P = 0.357), however, at 100 ft distance results were marginally significant (P = 0.057, post hoc = pot 1 > pot 2 > pot 3). Biomass changes by pot demonstrated a higher frequency of occurrence of catch rates increasing from pot 1 to pot 2 and fewer occasions when catch rates increased in pot 3 compared to pot 2 (Table 4.1.1). 9

13 4.2 Bycatch A total of fifteen finfish and five non-finfish bycatch species were caught in RCGL and control traps (Table 4.2.1). The number one ranking fish species in terms of relative abundance was the pigfish that represented 57.9 % of the total bycatch by number. The spot ranked second (21%) and the pinfish ranked third (7.4 %). Of the five non-finfish species caught the blue crab ranked number one in terms of relative abundance representing 65.1 % of the total catch. The majority of the bycatch were retrieved alive from the traps (95.8 %). Nine specimens were retrieved dead from the traps, five of which were in the control trap. Of those specimens retrieved alive from the traps the majority (95.9 %) were in a good condition and likely to survive the gear interaction. All finfish caught were juveniles based on their measured length-frequencies. The finfish:shrimp ratios ranged from 0.01:1 2:1 in control traps with an average of 0.04:1. The higher ratio was due to one occasion where shrimp catch rates were low coupled with an unusual high catch rate of pinfish. The same was true for RCGL traps with an unusually high catch rate on one occasion for pinfish resulting in ratios from 0.02:1 16:1 with an average of 0.11:1. 10

14 Figure Catch rate (lbs shrimp/trap/hour) of brown shrimp (Farfantepenaeus aztecus), pink shrimp (F. duorrarum) and white shrimp (Litopenaeus setiferus) combined in RCGL traps (n=150 trap sets) and control traps (n=25 trap sets). Probability (P) of RCGL CPUE data by month = < Post-hoc = Sept, August < July. Probability (P) for control trap CPUE data by month = Probability (P) of CPUE data by trap treatment = RCGL traps control traps CPUE Jul Aug Sept Trap set 11

15 Figure Count per lb of brown shrimp (Farfantepenaeus aztecus), pink shrimp (F. duorarum) and white shrimp (Litopenaeus setiferus) combined in RCGL traps (n=52 trap sets) and control traps (n=8 trap sets) for traps with 1 lb total shrimp catch. 9 8 Control RCGL 7 6 Frequency Count per lb 12

16 Table Relative abundance of all non-target species caught in RCGL shrimp traps and one control trap set in Topsail Sound, (n=175 trap sets). Common name Scientific name Total n Total n Rank FINFISH BYCATCH (RCGL traps) (control traps) Drums (Sciaenidae) spot Leiostomus xanthurus star drum Stellifer lanceolatus silver perch Bairdiella chrysoura Porgies (Sparidae) pinfish Lagodon rhomboides Grunts (Haemulidae) pigfish Orthopristis chrysoptera Anchovies (Engraulidae) striped anchovy Anchoa hepsetus Sea basses (Serranidae) gag Mycteroperca microlepis Flounders (Bothidae) gulf flounder Paralichthys albigutta Herrings (Clupeidae) Atlantic menhaden Brevoortia tyrannus Mullets (Mugilidae) white mullet Mugil curema Silversides (Atherinidae) Atlantic silverside Menidia menidia Tounguefishes (Cynoglossidae) blackcheek tonguefish Symphurus plagiusa Mojarras (Gerreidae) spotfin mojarra Eucinostomus argenteus Snappers (Lutjanidae) gray snapper Lutjanus griseus Toadfishes (Batrachoididae) oyster toadfish Opsanus tau Needlefishes (Belonidae) needlefish species TOTAL NON FIN-FISH BYCATCH Swimming crabs (Portunidae) blue crab Callinectes sapidus lesser blue crab Callinectes similis long wristed hermit crab Pagurus longicarpus Hermit crabs (Diogenidae) striped hermit crab Clibanarius vittatus Scallops bay scallop Argopecten irradians TOTAL

17 Table Shrimp biomass change (CPUE = lbs shrimp/trap/hour) by pot distance. Pot order in terms of shrimp interception is 1 3. An increase in biomass is indicated in red and prefixed by + otherwise data represent a decrease in biomass between pot treatment. Pot distance = 100 ft Pot distance = 50 ft pot 1-2 pot 2-3 pot 1-2 pot no set no set no set no set

18 5 DISCUSSION Three shrimp species are harvested in North Carolina (NC) coastal and inshore waters, brown shrimp (Farfantepenaeus aztecus), pink shrimp (F. duorarum) and white shrimp (Litopenaeus setiferus). There is some seasonal variation in their life stages resulting in two fisheries that use different gear arrangements in the summer and fall (NC Division of Marine Fisheries [NCDMF] 2006). The majority of shrimp are harvested using otter trawls in estuarine waters (NCDMF 1999) and a concern is the high level bycatch associated with this fishery. Juvenile finfish consititute a significant proportion of the bycatch in NC waters and includes commercially valuable species as well as those with limited or no economic value (Coale et al. 1994; Hines and Rulifson 1999; Logothetis and McCusiton 2005). Stock assessments of species such as Atlantic croaker (Micropogonias undulatus) and weakfish (Cynoscion regalis) also suggest that bycatch mortality is high enough to be a significant factor in negative population growth rates and population decline (Vaughan et al. 1991; Diamond et al. 2000). Bycatch reduction technology in the shrimp fishing industry increased in the 1980 s and 90 s (Watson et al. 1999) and alternative gears provide additional means to potentially reduce bycatch associated with the shrimp trawl fishery (Sessions and Thorpe 2006). One focus of this study was to determine the potential for commercial and RCGL shrimp trap use outside of Topsail Sound where they are currently reported to be used successfully. Previous research had demonstrated that commercial traps can be used successfully in the Topsail area although shrimp catch rates were disappointing as were state landings during their period of investigation (Sessions and Thorpe 2006). This study deployed commercial and RCGL traps in the Intracoastal Waterway (ICWW) north (Swansboro) and south (Brunswick County) of Topsail Beach. The results demonstrated limited success. Catch rates of shrimp in commercial traps set in Brunswick County were low primarily due to small shrimp length-frequencies that kept the commercial shrimp fishery closed for the whole summer. On one occasion there was an issue with finding suitable sites (behind Oak Island) although sets behind Holden Beach were made successfully. Shrimp are more usually associated with a sand-mix and/or vegetated substrata and this was documented as the dominant habitat type in the area, thus, there was a paucity of shrimp as evidenced by similarly low catch rates in the control trap (smaller mesh) and the commercial fishery remaining closed. The control trap was constructed of a smaller mesh to trap all shrimp in the area irrespective of size. 15

19 Other considerations for sub-optimal commercial trap performance outside of the Topsail area were; 1) Strong tidal currents, particularly in Brunswick County compared to Topsail; 2) Closer proximity of inlets to experimental sites in Topsail; 3) Extensive shallow flats in Topsail that facilitates shrimp movement close to the banks where they are intercepted by the traps. Clearly shrimp traps have a reduced bycatch potential compared to shrimp trawls. In 2006 average finfish to shrimp ratio for RCGL traps was 0.41:1 (Sessions and Thorpe 2006) and in this study average finfish to shrimp ratios were 0.11:1 (RCGL traps) and 0.04:1 (control traps). Shrimp trawl data from fishery independent research in internal waters of NC reported finfish to shrimp ratios of 7.62:1 for skimmer trawls and 8.41:1 for otter trawls (Coale et al. 1994), 2.08:1 for low profile and 1.63:1 for high profile skimmer trawls (Hines and Rulifson 1999), 1.6:1 for otter trawls (Diamond-Tissue 1999) and 2.32:1 for otter trawls (Logothetis and McCuiston 2005). The dominant finfish bycatch in shrimp trawls were also commercially important species, specifically Atlantic croaker (Micropogonias undulates), spot (Leiostomus xanthurus) and weakfish (Cynoscion regalis) (North Carolina Division of Marine Fisheries [NCDMF] 1999). RCGL trap data for 2006 reported a high bycatch rate of unmarketable species (> 90 %) that were primarily pinfish (Lagodon rhomboides) compared to pigfish (Orthopristis chrysoptera) and spot that were the dominant finfish species in this study and pinfish ranked third. The fishing mortality rate, however, was very low in traps and of the pigfish and spot caught only one specimen was retrieved dead from the traps (0.6 % fishing mortality rate). By comparison, the fishing mortality rate of finfish from trawls operating in internal waters of NC ranged from % (Coale et al. 1999; Logothetis and McCuiston 2005; Johnson 2006). In addition to low bycatch rates and high survival rates, traps select larger shrimp that are not subject to the crushing injuries typically seen in trawl caught shrimp, resulting in a high quality product. As a non-permanent staked gear there is minimal disturbance to soft-bottom habitats and the fishery is potentially available to a large segment of the population given low gear and operating costs. In 2006 NCDMF conducted an experimental shrimp trap evaluation (RCGL) along the NC coast from the SC line up to Morehead City (Brown and Price 2006). They also reported low shrimp catch rates with some improvement when they fished the ICWW behind Topsail beach (Brown, personal communication ). Similarly we found that RCGL traps worked well in the Topsail area with an average shrimp catch rate of 8oz (average soak time of 52 minutes). The highest catch rate was over 4 lbs shrimp/hour. RCGL traps were set and hauled by UNC-W biologists who had no prior experience with the gear. The RCGL gear was reported as being easy to use, portable, affordable, and caught enough shrimp for recreation purposes. Catch rates 2 K. Brown. NC Division of Marine Fisheries, Morehead City, NC 16

20 of shrimp may also increase with increasing distance between traps. While we did not see a decline in catch rates in pots set 50 ft or 100 ft apart, the trend was for increasing catch rates with increasing distance so our sets were likely close enough together so that differences were not detected between the two set treatments. Summary The use of RCGL traps to catch shrimp has much potential. While there may be a spatial component to their efficiency, they clearly catch shrimp in sufficient number in the ICWW behind Topsail Beach for recreation purposes. The bycatch is minimal and the condition of the bycatch is also primarily good with high survivor potential. Environment disturbance is minimal with it being a semi-permanent static gear and the quality of the product is high given that shrimp are not subject to gear related stress (i.e. crushing). Further, operation costs are low and the fishery is potentially available to a wide number of people. Some conflicts may occur between shrimp fishers in the ICWW and trap users although it is important to note that traps are set close to the banks and do not encroach into the navigable channel. Care should be taken to avoid user conflicts as much as possible. Acknowledgements We are very grateful to Dr. F. Scharf (UNC-W) for taking over the RCGL trap experiments in 2007 and for his review of the final report; Joe Facendola, Cassie Martin, and Bradley Tayloe for their hard work in the field; William Smith for field support and work on the databases; NC Sea Grant for funding the research. 17

21 References Brown, K., and B. Price Interstate Fisheries Management Program Implementation for North Carolina. Completion Report for NOAA Award No NA 05 NMFS Study II Documentation and Reduction of Bycatch in North Carolina Fisheries: Evaluation of experimental shrimp pots from Carteret County to Brunswick County, NC. 14 pp. Coale, J. S., R. A. Rulifson., J. D. Murray., and R. Hines Comparisons of shrimp catch and bycatch between a skimmer trawl and an otter trawl in the North Carolina inshore shrimp fishery. North American Journal of Fishery Management 14: Diamond, S. L., L. G. Cowell., and L. B. Crowder Population effects of shrimp trawl bycatch on Atlantic croaker. Canadian Journal of Fisheries and Aquatic Sciences 57: Hines. R., and R. A. Rulifson Performance of low-profile skimmer trawls in the inshore shrimp fishery of North Carolina. North American Journal of Fishery Management 19: Johnson, G. A Multispecies interactions in a fishery ecosystem and implications for fisheries management: The impacts of the estuarine shrimp trawl fishery in North Carolina. PhD dissertation, UNC-Chapel Hill, NC. 136 pp. Logothetis, E., and D. McCuiston An assessment of the bycatch generated in the commercial shrimp fishery in the inside waters of southeastern North Carolina. Final Report. North Carolina Sea Grant. 04-EP pp. National Marine Fisheries Service (NMFS) Cooperative research program addressing finfish bycatch in the Gulf of Mexico and South Atlantic shrimp fisheries: A report to Congress, April U.S. Department of Commerce, National Oceanic and Atmospheric Administration, NMFS, 9721 Executive Center Drive, St. Petersburg, FL North Carolina Division of Marine Fisheries (NCDMF) Shrimp and crab trawling in North Carolina's estuarine waters. A report to the NC Marine Fisheries Commission. Morehead City, NC. 54 pp. North Carolina Division of Marine Fisheries (NCDMF) North Carolina Fishery Management Plan: Shrimp. North Carolina Department of Environment and Natural Resources, DMF, 3441 Arendell Street, P.O.Box 769, Morehead City, NC pp. 18

22 Sessions, K., and T. Thorpe Catch potential and condition of shrimp and bycatch associated with a new commercial shrimp set design and new RCGL set design. Final Report to the North Carolina Marine Fisheries Commission, Fishery Resource Grant Program 05-FEG pp. Troffe, P. M., S. Ong., C. D. Levings., and T. F. Sutherland Anatomical damage to humpback shrimp, Pandalus hypsinotus (Brandt 1851) caught by trawling and trapping. Journal of Shellfish Research 22 (2): Vaughan, D. S., R. J. Seagraves., and K. West An assessment of the status of the Atlantic weakfish stock, Spec. Rep. No 21. Atlantic States Marine Fisheries Commission, Washington, DC. 19

23 APPENDIX I Dissemination of Information As a requirement of the funding agency (NC Sea Grant), dissemination efforts are reported here. This research project has generated much interest from the fishing industry and the general public. 1. A How To booklet is currently being compiled that describes how to make and fish the gear. It will also include set protocol as per the NC Division of Marine Fisheries. 2. Any opportunity to discuss shrimp traps with other fishers (recreational and commercial) was made. During trips while waiting for traps to soak, we often took the time to explain what we were doing to people on their docks and gave them sample shrimp. As a result inquires to UNC-W have been made by visitors to the area as well as local recreational and commercial fishers on how to make and set the gear. It seems that many people know about their traps and are interested in their application. 3. A presentation of preliminary findings was given to the SE Regional Committee in April