Nelson E J, Robinson S M C, Feindel N, Sterling A, Byrne A, Pee Ang K
Fisheries and Oceans Canada, St. Andrews, NB, Canada.
Department of Fisheries and Aquaculture, Shelburne, NS, Canada.
J Fish Dis. 2018 Jun;41(6):885-899. doi: 10.1111/jfd.12692. Epub 2017 Nov 21.
The sea louse, Lepeophtheirus salmonis, is parasitic to salmonid species in the Northern Hemisphere and has become a widespread biological and economic problem for the salmon farming industry. A better understanding is needed of their spatial distribution and early life history to disrupt the life cycle of the sea louse. In this study, sea lice larval densities within salmon farms, between salmon farms and reference sites, and at various depths were quantified using both plankton pumps and plankton nets. Farm sites exhibited significantly higher densities than reference sites; however, these densities dropped an order of magnitude at a distance of 100 m from the cages. The majority of the larvae captured in the study were nauplii (93%), and densities ranged from 0 to 10 larvae/m . Free-swimming sea lice larvae were found to exhibit a diel cycle where nauplii larvae were in deeper waters (10-17 m) during the day and in surface waters (1-6 m) during the night. The results of this study suggest that the early life-history stages of sea lice originate from and may remain close to active salmon farms, creating a self-sustaining population.
海虱（Lepeophtheirus salmonis）寄生于北半球的鲑科鱼类，已成为鲑鱼养殖业广泛存在的生物学和经济问题。需要更好地了解它们的空间分布和早期生活史，以破坏海虱的生命周期。在本研究中，使用浮游生物泵和浮游生物网对鲑鱼养殖场内、鲑鱼养殖场与参考站点之间以及不同深度的海虱幼虫密度进行了量化。养殖场的密度显著高于参考站点；然而，在距离网箱100米处，这些密度下降了一个数量级。研究中捕获的大多数幼虫是无节幼体（93%），密度范围为0至10只幼虫/立方米。发现自由游动的海虱幼虫呈现出昼夜周期，无节幼体幼虫白天在较深水域（10 - 17米），夜间在表层水域（1 - 6米）。本研究结果表明，海虱的早期生活史阶段起源于活跃的鲑鱼养殖场并可能在其附近，从而形成自我维持的种群。
