© 2004 by ICES/CIEM International Council for the Exploration of the Sea/Conseil International pour l'Exploration de la Mer
Survival of reared and wild Atlantic salmon smolts: size matters more in bad years
a University of Turku, Department of Biology, Section of Ecology FIN-20014 Turku, Finland
b Finnish Game and Fisheries Research Institute Bothnian Bay Fisheries Research Station, Jenssintie 2, FIN-95200 Simo, Finland
c Finnish Game and Fisheries Research Institute Quark Fisheries Research Station, Korsholmanpuistikko 16, FIN-65100 Vaasa, Finland
d Finnish Game and Fisheries Research Institute PO Box 6, FIN-00721 Helsinki, Finland
e Finnish Game and Fisheries Research Institute Taivalkoski Game and Fisheries Research, Ohtaojantie 19, FIN-93400 Taivalkoski, Finland
*Correspondence to I. Saloniemi. e-mail: irsalon{at}utu.fi.
We compared the marine survival of Carlin-tagged wild and hatchery-reared Atlantic salmon smolts of the Simojoki river, northern Baltic Sea. All the reared and released smolts were the offspring of native spawners returning to the river. Reared smolts were adipose-fin-clipped and released from the hatchery several weeks before tagging. The wild and reared smolts were simultaneously caught and tagged at a smolt trap located at the Simojoki river mouth. The study was conducted in two years, 1991 and 1993, when post-smolt survival in the Baltic Sea was different. Tags were returned by fishermen and return rates were used to estimate the survival of the smolt groups. We applied generalized linear models with survival as response variable and the year, origin, and smolt size as explanatory variables. On average, wild smolts had a 4.5 times higher survival rate than reared fish of the same smolt size. The difference in observed tag recovery rates as such was only about twofold or less, as the larger size of the reared smolts compared with the wild ones compensated for their lower survival rate. The better survival of wild than reared smolts was more pronounced in the low-survival year (1993 smolt year class) than in the high-survival year (1991 smolt year class).
Keywords: hatchery reared, salmon, smolt size, survival, tagging, wild
Received 21 August 2003; accepted 29 March 2004.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  S. D. McCormick Evolution of the hormonal control of animal performance: Insights from the seaward migration of salmon Integr. Comp. Biol., October 1, 2009; 49(4): 408 - 422. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. Jonsson and N. Jonsson Cultured Atlantic salmon in nature: a review of their ecology and interaction with wild fish ICES J. Mar. Sci., January 1, 2006; 63(7): 1162 - 1181. [Abstract] [Full Text] [PDF]
|
|