Final Report on the Nova Scotia Gear Selectivity Training Programme, 1997   Presented by David Tait, sr. and William Tait, Nordsea Limited for Nova Scotia Fisheries (R.I.T.C.) The Nova Scotia Department of Fisheries Human Resources Development Canada (H.R.D. C.) The Federation of Gulf Nova Scotia Ground Fishers (Fixed, Mobile, Less Than 45 Competitive)   EXECUTIVE SUMMARY The purpose of these experiments was to complement a comprehensive fisheries training program involving Nova Scotian inshore mobile fishers. The program was designed to demonstrate to the trainees the effectiveness of selectivity gear developments in Canadian and global fisheries, and illuminate their importance in establishing a responsible and sustainable fishery. One segment of the agenda was to examine the selectivity characteristics of codend mesh sizes and configuations. This experiment was conducted on board two vessels selected from the inshore mobile gear fleet in Nova Scotia. The program was intended for mobile ground fishers fishing with vessels 45 feet and under. Larger and more powerful vessels may experience different results from similar experiments. In the past the majority of mobile gear selectivity experiments have been conducted on more powerful offshore vessels. The plan was to conduct the program in four phases, the major components concentrated on training the fishers in selectivity procedures, and involved them in the entire selectivity experimental process from conception to completion. Phase One commenced with a series of seminars on selectivity methods and procedures held in Nova Scotia at Cheticamp, Bay St. Lawrence, Pictou, Antigonish, and Port Hood. The Seminars were very well received and coments positive. Addendum 1 and 2 contain the seminars schedule and a summary of attendees' comments. Phase Two consisted of training fishers on site at the trawl manufacturer and having them assist in the design and construction of experimental fishing gears. Phase Three involved instruction at sea on how to monitor, analyse, and collate data from a selectivity experiment. Phase Four was a presentation of the methodology and experiment results to industry. The experiments were conducted in NAAFO area 4Tg (figure 1), in depths of 15 to 25 fathoms. Strict project protocol was introduced by Nordsea Limited to ensure that the final results of phase three would withstand rigid scientific scrutiny. The trawling gear was continuously monitored using Scanmar equipment. Codend mesh size was frequently checked using an ICES gauge and a standard flat gauge. The experimental codends (figure 2) constructed for both vessel projects were four-seamed with no covers or chafing gear fitted, a lifting strap was placed on each codend, the netting was braided green double polyethylene. No selvedge ropes or strengthening ropes were fitted. The control codend was two-seamed and constructed of braided green 2.5mm single polyethylene. All codends were similar in circumference and length. The four codend configurations tested were: 140mm diamond mesh on top and bottom with square mesh side panels. Material. Double 4mm polyethylene. 140mm square mesh on top and bottom with diamond mesh side panels. Material. Double 4mm polyethylene. 140mm all square mesh. Material. Double 4mm polyethylene. 130mm square mesh on top and bottom with diamond side panels. Material. Double 4mm polyethylene. Control Codend: 55mm diamond mesh control codend. Material. Single 2.5mm polyethylene. All catches were measured and weighed according the the predetermined protocol and a small mesh control codend sampled the totalfish population. Frequency graphs and selectivity curves are presented. Prior to starting each experiment five tows were made with identical codends to check the validity of the experimental split nets. Results for the validity tests on the trawler show that the number of fish caught on each side was 50.26%/49.74%. This is not statistically different from a 50/50 split. Results for the validity tests on the Scottish seiner show that the number of fish caught on each side was 49.59%/50.41%. This is also not statistically different from a 50/50 split. Also the distribution lengths in both cases were not significantly. See figures 26 and 27. Retention curve parameters for the trawler "Amy Marie" for each gear: Gear 130 DS 140 DS 140 SD 140 SS 50% retention length 29.5 33.7 32.5 28.7 Selectivity range (cm) 4.5 6.0 5.0 4.0 Proportion in experimental gear 0.51 0.54 0.50 0.52 Retention curve parameters for the trawler "Celtic Pride" for each gear: Gear 130 DS 140 DS 140 SD 140 SS 50% retention length 28.0 30.1 33.2 31.4 Selectivity range (cm) 4.7 8.3 8.0 8.2 Proportion in experimental gear 0.40 0.56 0.72 0.52 The following is a summary of the comments from the attendees at the seminar: Thirty one of the attendees responded to the questionnaire. Almost all thought the timing of the seminar was good and the subjects were covered adequately. When asked what there should be more on, the replies, highest number of votes first, are as follows: a) Scottish seining b) selective methods for the under 45 foot fishery c) selective gears d) experimental trawls e) doors and net design When asked which aspects of the seminar were most interesting, the majority chose the videos and verbal presentation. Many liked all aspects, including the overheads and scale models. To summarize, the attendees were very positive in their reaction. They felt that the presentation was excellent, they had learned a great deal and would like the opportunity to attend more seminars on selectivity in the under 45 foot sector. One very telling comment was that information of this nature was a great help to fishers planning in their future.