Harrington Peter D, Cantrell Danielle L, Foreman Michael G G, Guo Ming, Lewis Mark A
Department of Mathematical and Statistical Sciences, University of Alberta, Edmonton, Alberta, Canada.
California Department of Fish and Wildlife, Marine Region's Fisheries Analytics Project, 20 Lower Ragsdale Drive, Suite 100, Monterey, CA 93940, USA.
R Soc Open Sci. 2023 Feb 8;10(2):220853. doi: 10.1098/rsos.220853. eCollection 2023 Feb.
Sea lice are a threat to the health of both wild and farmed salmon and an economic burden for salmon farms. With a free-living larval stage, sea lice can disperse tens of kilometres in the ocean between salmon farms, leading to connected sea louse populations that are difficult to control in isolation. In this paper, we develop a simple analytical model for the dispersal of sea lice () between two salmon farms. From the model, we calculate the arrival time distribution of sea lice dispersing between farms, as well as the level of cross-infection of sea lice. We also use numerical flows from a hydrodynamic model, coupled with a particle tracking model, to directly calculate the arrival time of sea lice dispersing between two farms in the Broughton Archipelago, British Columbia, in order to fit our analytical model and find realistic parameter estimates. Using the parametrized analytical model, we show that there is often an intermediate interfarm spacing that maximizes the level of cross-infection between farms, and that increased temperatures will lead to increased levels of cross-infection.
海虱对野生和养殖鲑鱼的健康都构成威胁，也是鲑鱼养殖场的经济负担。由于海虱有一个自由生活的幼虫阶段，它们可以在海洋中在鲑鱼养殖场之间扩散数十公里，导致海虱种群相互关联，难以单独控制。在本文中，我们开发了一个简单的分析模型，用于模拟海虱在两个鲑鱼养殖场之间的扩散情况。通过该模型，我们计算了海虱在养殖场之间扩散的到达时间分布，以及海虱的交叉感染水平。我们还使用水动力模型的数值流，并结合粒子跟踪模型，直接计算不列颠哥伦比亚省布劳顿群岛两个养殖场之间海虱的到达时间，以拟合我们的分析模型并找到实际的参数估计值。使用参数化的分析模型，我们表明，通常存在一个中间的养殖场间距，可使养殖场之间的交叉感染水平最大化，而且温度升高会导致交叉感染水平增加。
