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Appendix 



Description and construction diagram for 

 the trawl and the auxiliary net 



Poly Nor'eastern survey bottom trawl The Poly Nor' 

 eastern is a high-rise, 4-seam, trawl rigged with rubber 

 bobbin roller gear designed for use on moderately rocky 

 terrain (Appdx. Fig.l). The net is constructed of 12.7-cm 

 stretched-mesh polyethylene web (4-mm thickness top 

 and sides, 5-mm thickness in the bottom and intermedi- 



ate sections) and has a double 8.9-cm (4-mm thickness) 

 codend with a 3.2-cm nylon mesh liner. The 27.2-m 

 headrope supports twenty 30.5-cm diameter and four 

 20.3-cm diameter trawl floats that provide 220 kg of 

 total lift. The webbing is hung from a 24.9-m bolsh 

 line consisting of 0.95-cm diameter bare stranded wire 

 wrapped with 0.95-cm diameter polypropylene rope, that 

 attaches to a 24.7-m chain (1.6-cm long-link) fishing line. 

 The 24.2-m, 1.9-cm diameter stranded-wire footrope is 

 rigged with three sections of roller gear that attach to 

 the fishing line with 25-cm pieces of 0.95-cm chain. The 

 12.2-m center section of the roller gear consists of eight 

 36-cm rubber bobbins separated by 10-cm rubber disks. 

 To either side of the center segment is a 6.0-m section 

 that consists of four 36-cm rubber bobbins separated 

 by pieces of rubber hose to protect the wire footrope. 

 In addition, 5.9-m footrope wing extensions consisting 

 of 1.9-cm diameter stranded-wire rope with 10-cm and 

 20-cm rubber disks span the lower "flying" wing section 

 on each side of the net. Riblines, constructed of 1.9-cm 

 diameter Duralon 2 in 1 braided rope (Samson Inc., 

 Ferndale, WA), are hung along 98% of the stretched 

 length of the netting. 



The net is connected to a pair of 1.8x2.7 m steel "V" 

 doors, weighing approximately 816 kg each, by two 3-m 

 door legs, consisting of 1.6-cm long-link chain; a 12.2-m 

 door leg extension, consisting of 1.9-cm diameter bare 

 stranded wire; and triple 54.9-m bridles, consisting of 

 1.6-cm diameter bare stranded wire, on each side of the 

 net. Additional 46-cm and 23-cm-long extensions, con- 

 sisting of 1.3-cm long-link chain, connect the upper and 

 middle bridles to the respective wing tips of the trawl. 



Auxiliary net for Poly Nor'eastern trawl gear The aux- 

 iliary net is a 2-seam trawl fitted with small side panels 

 designed to help maintain steady footrope contact with 

 the bottom during periods of intermittent contact by 

 the Poly Nor'eastern footrope; it also fitted with three 

 codends for catch retention should the net sustain dam- 

 ages (Appdx. Fig. 2). The 24.8-m headrope, constructed 

 of 1.9-cm diameter double braid polyester rope, is lashed 

 to the survey trawl bolsh line. The 28.0-m footrope, 

 constructed of 1.3-cm long-link chain passing through 

 12.7-cm diameter rubber disks, is lashed to the 1.9-cm 

 diameter double braid polyester fishing line from which 

 the netting is hung. A delta plate located just aft of each 

 survey trawl wing extension is used to connect both the 

 front ends of the headrope and the fishing line to the 

 trawl footrope. 



With the exception of the 8.9-cm stretched-mesh co- 

 dends, the net is constructed of 10.2-cm stretched-mesh 

 polyethylene web (4 mm in body and codend and 5 mm 

 in the wings and mouth area of the lower panel). For 

 added protection, netting was doubled on the leading 

 wing edges of the upper panel, the wings and mouth 

 areas of the lower panel, the forward meshes of the side 

 panels, the aft 10 meshes of the intermediate section, 

 and throughout the codends. Riblines, constructed of 

 1.6-cm diameter poly dacron twisted rope, were hung 

 along 92.5% of the stretched length of the netting. 



