Spawning migration of brown trout, Salmo trutta, in the Moravka reservoir
2007
Piecuch, J.,Ostravska Univ. (Czech Republic). Prirodovedecka Fakulta | Lojkasek, B.,Ostravska Univ. (Czech Republic). Prirodovedecka Fakulta | Lusk, S.,Akademie Ved, Brno (Czech Republic). Ustav Biologie Obratlovcu | Marek, T.,Povodi Odry, Frydek-Mistek (Czech Republic)
The spawning migration from Moravka reservoir to the Moravka river tributary of brown trout in autumn (October-November) lasted 22, 24, and 27 days, respectively, in the seasons 2002-2004. In 2002, 187 fish were trapped, whereas the number of trapped spawners increased to 447 in 2003 and 2,230 in 2004. Spawning males were significantly longer than females. In 2002, more females than males migrated. The sex ratio in the following seasons did not significantly differ from 1:1. Spawning migration started under the conditions of increasing water levels, when the water temperature decreased below 8 deg C in the reservoir. The peak of spawning, in all three seasons, took place between 28 October and 3 November, the river temperature varied from 6 to 8 deg C. The spawning in 2002 was more nocturnal than diurnal and the diel activity showed a multimodal distribution. The different environmental variables and their interactions were significantly related to the spawning migration only in 2003 and 2004.
显示更多 [+] 显示较少 [-]