. Commercial fisheries review. Fisheries; Fish trade. Fig. 1 - Diagram of design and rigging for the 5-meter lift net (N) and the underwater lamp and echo-sounder transducer mounting platform (L), during fishing. The net was rigged with 3 separate lift lines because a bridle caused a fright response and the fish evaded capture. The 3 lift lines produced some vibrations during a lift, but they did not elicit fright re- actions - -and the fish were not much disturbed before visually detecting the net. The visual fright stimulus produced by the net's ap- proach was reduced by makingthe top 10-foo
. Commercial fisheries review. Fisheries; Fish trade. Fig. 1 - Diagram of design and rigging for the 5-meter lift net (N) and the underwater lamp and echo-sounder transducer mounting platform (L), during fishing. The net was rigged with 3 separate lift lines because a bridle caused a fright response and the fish evaded capture. The 3 lift lines produced some vibrations during a lift, but they did not elicit fright re- actions - -and the fish were not much disturbed before visually detecting the net. The visual fright stimulus produced by the net's ap- proach was reduced by makingthe top 10-foot section of webbing hang straight down from hoop before tapering to cod end. Although pressure wave that precedes rising net was not measured, the straight-side design also may have reduced this pressure wave, or lowered it to within the net opening. LIFT NET HOOP DESIGN The lift net hoop was made by rolling a 2- by 2- by ^-inch angle iron and a 1-inch iron pipe to a 5-meter ( feet) diameter circle and welding the iron pipe to the angle iron. The hoop was constructed in 2 equal parts bolted together with overlapping angle-iron stiffeners (Fig. 2). This construction per- mits hoop to be dismantled for easy storing. &"bolt Tlj. â CONT. WELD. ^ s 9 9 9 « % ⢠9 9 "V 9\ 9 9 9 9 9 9 9 9 9 -^ jCONT WELD SECTION - AA. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original United States. National Marine Fisheries Service; U. S. Fish and Wildlife Service; United States. Bureau of Commericial Fisheries. [Washington] : National Marine Fisheries Service; [for sale by the Supt. of Docs. , U. S. Govt. Print. Off. ]
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Keywords: ., book, bookcentury1900, booksubjectfisheries, booksubjectfishtrade
