School of Ocean Sciences, College of Natural Sciences, Bangor University, Askew Street, Menai Bridge, Anglesey LL59 5AB, United Kingdom.
Mar Environ Res. 2012 Feb;73:85-95. doi: 10.1016/j.marenvres.2011.11.009. Epub 2011 Nov 15.
The negative impact of demersal fishing gears on the marine environment may be mitigated by utilizing less damaging fishing gears. Within this context three queen scallop fishing gears were tested for their catch efficiencies and their environmental impact on benthos: a traditional 'Newhaven' dredge, a new dredge design with a rubber lip instead of the traditional teeth as its main new design feature and an otter trawl. Both, the new dredge and the otter trawl showed high catches and relatively low by-catches. Catches made with the traditional dredge were lower and contained larger amounts of non-target species. Both dredges primarily caught invertebrate species, while by-catches of the otter trawl were dominated by demersal fish. The impact of these gears on the benthic biota demonstrated that while no effects were detected for the otter trawl both dredges showed similar negative effects. Clear negative effects were evident for the brittlestar Ophiura ophiura while positive trends for the common starfish Asterias rubens and the hermit crab Pagurus bernhardus indicated scavenging effects. Due to its higher catch efficiency the new dredge caused less damage per unit catch compared to the traditional dredge, yet compared to the otter trawl it appears less environmentally friendly. However, the new dredge may be an alternative to the otter trawls for fisheries where the by-catch of demersal fish has been identified as a significant problem.
底拖网渔具对海洋环境的负面影响可以通过使用破坏性更小的渔具来减轻。在这方面，我们测试了三种女王扇贝捕捞渔具的捕捞效率及其对底栖生物的环境影响：一种传统的“纽黑文”拖网、一种新型拖网，其主要新设计特点是用橡胶唇而不是传统的牙齿、一种鼬鱼拖网。新型拖网和鼬鱼拖网的捕捞量都很高，兼捕量相对较低。传统拖网的捕捞量较低，且包含更多的非目标物种。两种拖网主要捕捞无脊椎动物，而鼬鱼拖网的兼捕物主要是底栖鱼类。这些渔具对底栖生物群的影响表明，虽然鼬鱼拖网没有检测到任何影响，但两种拖网都显示出类似的负面影响。对脆弱星 Ophiura ophiura 的影响明显是负面的，而对常见的海星 Asterias rubens 和寄居蟹 Pagurus bernhardus 的影响则呈积极趋势，表明存在清道夫效应。由于新型拖网的捕捞效率更高，因此每单位捕捞量造成的破坏比传统拖网小，但与鼬鱼拖网相比，它对环境的影响似乎较小。然而，对于底栖鱼类兼捕量已被确定为一个重大问题的渔业来说，新型拖网可能是鼬鱼拖网的一种替代选择。
