REDNET - a Network to Redevelop a Sustainable Redfish (Sebastes Fasciatus) Trawl Fishery in the Gulf of Maine

REDNET - a Network to Redevelop a Sustainable Redfish (Sebastes Fasciatus) Trawl Fishery in the Gulf of Maine

REDNET - A Network to Redevelop a Sustainable Redfish (Sebastes fasciatus) Trawl Fishery in the Gulf of Maine DRAFT FINAL REPORT Date: 16 May 2016 Written by: Michael Pol Massachusetts Division of Marine Fisheries On behalf of co-Network Coordinators Pingguo He UMass Dartmouth School for Marine Science and Technology and Sally Sherman (beginning June 2013) Kohl Kanwit (until June 2013) Maine Department of Marine Resources Funded by: Northeast Cooperative Research Partners Program Northeast Fisheries Science Center National Marine Fisheries Service NOAA Contract Number EA133F10CN0323 1 REDNET Draft Final Report 2 I. Abstract The goal of the REDNET project was to devise strategies and means to sustainably harvest the abundant Acadian redfish resource in the Gulf of Maine through a network approach, including fishing enterprises, gear manufacturers, researchers, social and economic experts and managers. The network defined the research pathway for conceiving, developing and implementing research, development and outreach strategies to sustainably access to the redfish resource under the current sector and ACL management regime. The vision was a comprehensive, integrated, well-planned project where the intent of every step is toward an environmentally and economically sustainable redfish fishery. A network of forty or more participants from all facets of fishing was developed, along with strategies of consensus and openness, to facilitate and to improve the effectiveness of REDNET activities and research. Major information gathering, sharing and decision making occurred at six major meetings during the life of the REDNET contract, and in-between via email and telephone calls. The network was largely highly flexible, expanding and contracting as needs warranted. The completion of a substantial amount of work indicates that the network was an overall success. Structured and monitored exploratory fishing using five commercial fishing vessels in every two to three months between the end of May 2011 and January 2012 revealed low amounts of bycatch, with redfish comprising 94.9% of all catch. The vessels used their own commercial groundfish trawls, but a relatively small mesh codend (114 mm or 4.5” mesh size, double twine diamond). Each vessel fished 4-5 days with a total of 85 tows, ranging from 15 to 20 tows per trip (per vessel). Fishing was carried out on traditional redfish grounds throughout the central portion of the Gulf of Maine at depths ranging from 77 fm to 138 fm. The amount of redfish caught per trip ranged from about 35,000 to 67,000 lbs and the catch per tow ranged from 0 to 13,655 lb, averaging 2,766 lb. Total kept and landed redfish were 221,957 lbs, or 95.5% of all redfish caught. Pollock (Pollachius virens) was the main landed bycatch species (7,307 lb), with 13 other species landed in smaller amounts with only spiny dogfish exceeding an SBRM of 0.01. Results indicated that harvesting redfish with a 4.5 in diamond mesh could be conducted without substantial catch of undersized redfish and other commercially important species. The size of redfish caught may be further reduced through codend mesh size adjustment or using size-sorting devices. Measurement of codend mesh size selectivity of three sizes of mesh opening (4.5, 5.5 and 6.5 in double 5 mm twine diamond) was conducted using a trouser trawl on a commercial fishing vessel. Fishing off Provincetown, Massachusetts, 56 tows were completed in March and April 2013, catching over 42,000 kg of redfish and about 6,000 kg of other species. Adequate length frequencies of redfish and pollock (Pollachius virens) were collected to produce selectivity models; only redfish results are reported here. Neither species has been the subject of a trawl selectivity study in the Northeast US before. REDNET Draft Final Report 3 Robust models for the mean L50s and selection ranges, and confidence intervals, were developed for all three tested codends, incorporating both within and between haul variability. All measures of model validity were positive. These models are fully adequate to provide guidance to managers and fishermen on size retention of redfish and appropriate codend mesh size. L50 and selection ranges were determined for 4.5 in (L50: 22.3 cm (8.8 in); SR: 4.5 cm), 5.5 in (L50: 29.2 cm (11.5 in); SR: 4.4 cm), and 6.5 in (L50: 33.6 cm (13.2 in); SR: 5.1 cm) codends. Simulation of fishing of the three tested codends on the observed population indicated that substantial escape of redfish through codend meshes occurs (48-94%), suggesting that investigation of escape of redfish is warranted to support a sustainable fishery. The observed population also indicates that inadequate numbers of larger redfish may be available to support a higher-priced market. Choice of an appropriate mesh size, special access program, marketing strategy, and other factors are linked to mortality of small redfish. Small redfish that are excluded or escape during fishing and die as a result are unobserved and unquantified and this unaccounting can impact stock assessments. Small redfish brought to the surface and onto the deck likely die, but can be quantified. In order to weigh the costs and benefits of management choices, more information on location of redfish escapes was sought. Redfish that escape through codend meshes at bottom experience fewer sources of injury and mortality. To provide more information on the fate of small redfish, we deployed cameras on redfish codends, with the goal of determining when and where escapes occur. To investigate a means of encouraging escape at bottom, we tested a dual-grid system designed to exclude smaller redfish and allow larger redfish to pass to the codend. Testing occurred on a commercial redfish trawler northeast of Provincetown, Massachusetts in July and August 2014. A trouser trawl section attached to a redfish net allowed simultaneous comparison of catches in two codends. For escapement, catches of redfish in a 2.5 in codend were compared to catches in a 4.5 in codend to estimate the number of escapes. Video cameras on the top and bottom of the codend were used to count escapes and the depths at which they occurred. For dual-grid testing, a 4.5 inch codend was attached to one leg, and the dual-grid system plus a 4.5 inch codend was attached to the other. Results from escapement trials indicated that a small portion of total escapes were captured on video, perhaps due to sediment or other factors. Due to camera failures, the sample size was small. Most observed escapement occurred during haulback (on average, over 70%), a relatively brief portion of the haul. Results are preliminary, and video and other data require further analysis. Dual grid testing showed no reduction or length effect due to the 40 mm grid spacing. The 50 mm grid spacing showed a reduction at all lengths, suggesting that a grid system could be tuned to reduce only small fish. Adjusting and deploying the grid system presented some challenges. REDNET Draft Final Report 4 Further refinement of a dual grid system would be necessary for commercial application, but preliminary results indicate that a large proportion of redfish escapes likely occurs during haulback, suggesting that a grid system could reduce injury and delayed mortality of small redfish. Results from the processing and marketing component revealed large price variation when landings of redfish were low, and higher variation when landings were higher. Processing capacity did not limit the price of redfish. It was suggested from the results of this component that an alternative to reduction of the catch of smaller redfish (7-8 in) is the development of human consumption instead of a bait market for these fish. This type of development would require processor and consumer testing beyond the duration of REDNET. Based on our results, most restaurant managers do not serve redfish but prefer locally landed (Massachusetts) fish. This finding implies that consistent redfish landings may encourage more restaurant owners to serve locally landed fresh redfish. Marketing programs, including eco-labeling, to raise the price of redfish would be challenged by redfish imports from Canada, which sell for less than half the price of redfish landed in New England. The consensus of marketing experts in the group was that continuity and stability (i.e. confidence) of supply would create demand. Markets are known (and kept as trade secrets) by marketers and could be developed. Sectors or other industry groups could coordinate activities to keep markets supplied consistently without over- or under-supply. However, a networked approach may not facilitate marketing due to competitive concerns and proprietary information. An outreach plan was developed, but only partly implemented due in part to the completion of experiments late in the project and the ending of the contract. Tradeoffs from possible management actions were described based on output from the multiple components of REDNET. REDNET Draft Final Report 5 II. Goals, Objectives, and Value An Acadian redfish (Sebastes fasciatus – hereafter referred to as “redfish”) Annual Catch Limit (ACL) of 6,848 mt available to sectors beginning May 1, 2010 remained largely untapped due to the lack of development of a sustainable and responsible harvest strategy and trawl gear technology. The implementation of sectors with catch retention rules and accountability measures made targeting redfish difficult. We proposed to establish and use the resources of a redfish network to develop a comprehensive research plan that draws on wide-ranging expertise and to conduct comprehensive research including bycatch assessment, gear testing, processing and marketing, outreach and implementation. Goal: The goal of the project was to devise strategies and means to sustainably harvest the redfish resource in the Gulf of Maine through a network approach, including fishing enterprises, gear manufacturers, researchers, social and economic experts and managers.

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