Norwegian Veterinary Institute, PO Box 750 Sentrum, 0106 Oslo, Norway.
Proc Biol Sci. 2012 Jun 22;279(1737):2330-8. doi: 10.1098/rspb.2012.0084. Epub 2012 Feb 8.
Fisheries catches worldwide have shown no increase over the last two decades, while aquaculture has been booming. To cover the demand for fish in the growing human population, continued high growth rates in aquaculture are needed. A potential constraint to such growth is infectious diseases, as disease transmission rates are expected to increase with increasing densities of farmed fish. Using an extensive dataset from all farms growing salmonids along the Norwegian coast, we document that densities of farmed salmonids surrounding individual farms have a strong effect on farm levels of parasitic sea lice and efforts to control sea lice infections. Furthermore, increased intervention efforts have been unsuccessful in controlling elevated infection levels in high salmonid density areas in 2009-2010. Our results emphasize host density effects of farmed salmonids on the population dynamics of sea lice and suggest that parasitic sea lice represent a potent negative feedback mechanism that may limit sustainable spatial densities of farmed salmonids.
在过去的二十年中,全球渔业捕捞量没有增加,而水产养殖业却蓬勃发展。为了满足不断增长的人口对鱼类的需求,水产养殖业需要继续保持高速增长。这种增长的一个潜在限制因素是传染病,因为随着养殖鱼类密度的增加,疾病传播的速度预计会加快。利用来自挪威沿海所有养殖鲑鱼的大量数据,我们记录了养殖场周围养殖鲑鱼的密度对养殖场寄生虫性海虱的水平以及控制海虱感染的努力有很大的影响。此外,在 2009-2010 年,增加干预措施也未能成功控制高密度鲑鱼区的高感染水平。我们的研究结果强调了养殖鲑鱼的宿主密度对海虱种群动态的影响,并表明寄生虫性海虱代表了一种强大的负反馈机制,可能限制了养殖鲑鱼的可持续空间密度。