overlook during the era of cheap energy. Bottom friction (large and unwieldy doors often get caught up in the shrimp nets or hung up on the ocean floor) and drag from the considerable weight and size of the doors can add up to a hefty fuel bill. Smith's beam trawl is designed to do the same job as the otter doors, but in a way that is more energy- and cost-efficient. His first design was a 45-foot beam with two 13-foot movable staffs attached to each end. The staffs can spread the net open to twice the height reached by the 6-foot-high doors. Although it performed well, getting the beam on and off the boat was a problem because the open net caused resistance in the water, and the long beam was unwieldy. An alternative design was a "box" beam that could be "folded" in the middle, reducing net resistance and making the beam easier to handle. Unfortunately, this one was also too big and bulky. The third time around. Smith designed a sliding beam that does not have the problems of the first two. The net is attached to a staff permanently secured to one end of the beam. The staff on the other end is connected to the beam by a collar with a spring-loaded catch (see diagram). When the catch is released, the collar slides along the beam, like a ring on a finger, bringing the two staffs together and collapsing the net. The shrimper then lifts the net with a hook and hauls the beam on board where it is stored standing upright. The sliding beam has several advantages over the conventional otter doors. First, it costs about half as much as the doors. Second, because of its reduced size and weight (200-lb. beam vs. 1600-lb. doors), it causes less drag and therefore cuts fuel costs by 25 to 30 percent (saving about $7500/yr. on an average boat). Third, the beam doesn't require a traditional net designed to open in the water since the staffs keep the net open. Consequently, a "sack" net is sufficient, and it costs less to purchase and repair. Fourth, a 45-foot beam has a 45foot net that opens to its full width of 45 feet. In contrast, a set of otter doors with a 90-foot net gets a maximum net spread of 45 feet. Fifth, the beam requires fewer floats to keep the net open since the beam is doing most of the work. Finally, the beam can be easily stored on the boat. It is lighter, and, because it is stored upright, it leaves more deck space for storage of gear and shrimp. The challenge at this point is to convince shrimpers that it is worth their while to switch to the beam trawl; it means scrapping the effective, but costly, otter doors and learning about an unfamiliar technology. In order to demonstrate the safety and technique of handling the beam on an average-sized (65- to 90-foot) boat, a leading shrimper ocean-tested the beam against his otter doors with their 90-foot net. He set up the beam on one side of the boat and the otter doors on the other. The results? The beam caught the same amount of shrimp as the door but caused much less drag; however, it was still a bit difficult to handle out of water. Such positive results suggest that commercial application of the design should follow naturally. However, as previously noted. Smith has found that shrimpers are reluctant to make the switch from otter doors to the beam trawl—an example of proven tradition winning out over promising innovation. Yaquina Boat Works continues to use the beam on one of its boats, but Smith realizes it will be a long time before his local and international colleagues will consider a switch. He plans to keep testing and modifying the beam so that it can be easily used on the larger boats. The beam trawl has been used in the Gulf of Mexico and is easily adapted to net fishing anywhere in the world; it offers both economic incentives and conservation benefits to fishing operations. With continued demonstration and testing, the beam trawl is bound to catch on in time. (Paul Smith, Yaquina Boat Works, Inc., 508 Butler Bridge Rd., Toledo, OR 97391.) □ □ Oct./Nov. 1983 RAIN Page 47
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