The University of British Columbia, Centre for Aquaculture and Environmental Research, 4160 Marine Drive, West Vancouver, BC, Canada.
J Fish Biol. 2011 Feb;78(2):624-34. doi: 10.1111/j.1095-8649.2010.02882.x. Epub 2011 Jan 7.
The early marine migratory behaviour of two populations of hatchery-reared Atlantic salmon Salmo salar was compared in a common-garden experiment. Post-smolts from a river in a long fjord (Laerdal River, 144 km from the open coastline, n = 79) and a short fjord (Flekke River, 20 km from the open coastline, n = 80) in western Norway were tagged with acoustic transmitters and released during the spring of 2005 and 2006 in the inner part of the Hardangerfjord system (Opo River mouth, 179 km from the open coastline). The migratory behaviour of the tagged fish was monitored by acoustic listening stations in the fjord system up to 167 km from the release site. The Laerdal fish began migrating before the Flekke fish and had higher progression rates in the middle part of the fjord system. A greater number of Laerdal fish was detected along the most direct migratory route and in the outermost part of the Hardangerfjord system, which is indicative of a higher survival. The results from this study demonstrate differences in early marine migratory behaviour between S. salar from two different stocks and suggest that the distance a S. salar population travels to reach the open coastline may influence its early marine migratory behaviour and performance. The selective pressures of marine predation and arrival time at feeding areas in the ocean may be stronger for stocks with a longer inshore migration, creating more efficient migrants over time.
在一项对比实验中，研究人员比较了两个人工养殖大西洋鲑种群的早期海洋洄游行为。来自长峡湾（拉达尔河，距离开阔海岸线 144 公里，n = 79）和短峡湾（弗莱克河，距离开阔海岸线 20 公里，n = 80）的幼鲑被贴上声学标签，并于 2005 年和 2006 年春季在哈当厄尔峡湾系统内部（奥普河河口，距离开阔海岸线 179 公里）释放。通过峡湾系统中的声学监听站监测标记鱼的洄游行为，直到距离释放点 167 公里处。拉达尔鱼比弗莱克鱼更早开始洄游，并且在峡湾系统的中部区域具有更高的迁移速度。更多的拉达尔鱼被检测到沿着最直接的洄游路线和哈当厄尔峡湾系统的最外部分，这表明它们的存活率更高。这项研究的结果表明，来自两个不同种群的大西洋鲑的早期海洋洄游行为存在差异，并表明鲑鱼种群到达开阔海岸线的距离可能会影响其早期海洋洄游行为和表现。海洋捕食和到达海洋觅食区的时间等选择性压力对于具有较长近岸迁移距离的种群更强，随着时间的推移，会产生更高效的洄游者。
