Fate of discards from deep water crustacean trawl fishery off the south coast of Portugal
Fate of discards from deep water crustacean trawl fishery off the south coast of Portugal
复制标题
DOI：
10.1080/00288330.2005.9517323
复制
发表时间：
2005-01-01
影响因子：
1.6
通讯作者：
Monteiro, P
中科院分区：
文献类型：
--
作者：
Castro, M;Araújo, A;Monteiro, P
在葡萄牙南海岸 200 至 800 m 的深度进行拖网捕捞甲壳类动物。大量丢弃物被释放回大海，到达拖网作业区域的底部。这项工作的目的是研究丢弃物分解所需的时间，确定所涉及的最重要的清除物种，并评估对渔业目标物种的影响。我们使用用丢弃物样本作为诱饵的陷阱进行了 22 次系列试验。浸泡时间在 1 小时到 40 小时之间变化。从丢弃物中取出的组织量按 1-3 的定性等级进行评估，并进行定量评估。陷阱中捕获的物种已被识别。浸泡5小时后，饵料已被大量消耗。浸泡24小时后只剩下鱼刺； 40小时过去，消耗完毕。海鳗（Conger conger）是陷阱中最常见的鱼类。端足类 Scopelocheirus Hopei 和等脚类 Natatolana (Cirolana) borealis 两个物种被认为对系统中有机物的回收最重要。对拖网捕获的物种样本的胃内容物进行了分析，以确定是否存在小型食腐动物。初步结果表明，希望虾和北极虾是该渔业的一些目标物种的饮食的一部分，例如挪威龙虾、挪威龙虾和玫瑰虾长对虾。
Trawling for crustaceans takes place on the south coast of Portugal at depths between 200 and 800 m. Large amounts of discards are released back to sea, reaching the bottom in the general area where trawling occurs. The objective of this work was to study the time taken for decomposition of the discards, to identify the most important scavenging species involved, and to evaluate the impact on the species targeted by the fishery. We conducted a series of 22 trials, using traps baited with samples of the discards. The time of immersion varied between I and 40 h. The amount of tissue removed from the discards was evaluated on a qualitative scale of 1-3, and quantitatively. The species caught in the traps were identified. Considerable consumption of the bait had occurred after 5 h of immersion. After 24 h of immersion only fish bones were left; past 40 h, consumption was complete. The conger eel (Conger conger) was the most common fish species present in the traps. Two species, the amphipod Scopelocheirus hopei and the isopod Natatolana (Cirolana) borealis, were identified as most important for the recycling of organic matter in the system. The stomach contents of a sample of species caught in trawls were analysed for the presence of small scavengers. Preliminary results show that S. hopei and N. (C.) borealis are part of the diet of some of the target species of this fishery, such as the Norway lobster, Nephrops norvegicus and the rose shrimp Parapenaeus longirostris.