Armstrong J D, McKelvey S, Smith G W, Rycroft P, Fryer R J
Freshwater Fisheries Laboratory, Marine Scotland Science Faskally, Pitlochry, Perthshire, PH16 5LB, U.K.
Cromarty Firth Fishery Trust, CKD Galbraith, Reay House, 17 Old Edinburgh Road, Inverness, IV2 3HF, U.K.
J Fish Biol. 2018 Mar;92(3):569-578. doi: 10.1111/jfb.13548.
Groups of wild-reared Atlantic salmon Salmo salar smolts were captured during their seaward migration on a tributary of the River Conon, Scotland, U.K., from 1999 to 2014 and tagged with passive integrated transponders (PIT). Fish that subsequently returned to the river after growing at sea were recorded automatically by a PIT-detector in a fish pass. Return rate was related directly to length and condition and inversely to day of the year that the smolt was tagged. Over years, as the study progressed, there was a significant increase in the proportion of smolts returning after two or more years at sea and no trend in returns of salmon having spent one winter at sea. There was no trend in the date of return of salmon across the study period. Fish that had spent more winters at sea returned earlier in the year.
1999年至2014年期间，在英国苏格兰科农河的一条支流上，对洄游入海的野生大西洋鲑（Salmo salar）幼鱼进行分组捕获，并用无源集成应答器（PIT）进行标记。在海里生长后返回河流的鱼，会被鱼道中的PIT探测器自动记录下来。洄游率与鱼的长度和健康状况直接相关，与幼鱼被标记的日期呈负相关。多年来，随着研究的进行，在海上生活两年或更长时间后返回的幼鱼比例显著增加，而在海上度过一个冬天的鲑鱼的洄游率没有趋势变化。在整个研究期间，鲑鱼的返回日期没有趋势变化。在海上度过更多冬天的鱼在一年中更早返回。
