摘要
The timing of the smolt run in the Dale River in western Norway was monitored from 2002 to 2007 after annual stocking in late autumn 2000 to 2005 with 5000-10800, 11-16 g, Atlantic salmon, Salmo salar L., parr. The releases yielded an annual smolt production of 1000-2000 individuals, mainly 1+ smolts. Almost 5700 stocked smolts were trapped during smolt migration and 60% of these were genotyped for family identification. The date for 50% descent varied by 14 days from year to year. For the most part, however, the 2+ stocked smolts and the majority of the wild smolts left the river in May, while the 1+ stocked smolts migrated 23-26 days later in June. It was concluded that the strategy of stocking large parr in late autumn may conflict with the natural timing of smolt migration the following spring.
- 出版日期2010-12