The aim of this study was to evaluate the material about the asp Leuciscus aspius (L., 1758) from the dam Želivka - Švihov in the years 1971 - 2014. Main emphasis was put on the analysis of the flock spawning from 2008 - 2014. Here, basic abiotic conditions were monitored at the time of the spawning and growth and population characteristics were calculated. Spawning took place at two locations, at 4 - 10 0 C, the asp showed a spawning site accuracy. Males predominated on the spawning grounds in the overall ratio of 1,22 : 1. The age of the fish examined ranged from 3+ to 13+. The average mortality of adults is about 0,4. Additional flock spawning ranges from 20 to 50%. The length at which scales begin to form (SL = 29,7 mm), was determined by using the rate between the body length and scale radius. Differences in the growth rates between males a females are minimal, only from the third to the fifth age group, males showed a higher growth rates. The length - weight relationship can be described as W = 0,0153. L3,19 .
| Identifer | oai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:337625 |
| Date | January 2014 |
| Creators | Bouše, Eduard |
| Contributors | Švátora, Miroslav, Pivnička, Karel |
| Source Sets | Czech ETDs |
| Language | Czech |
| Detected Language | English |
| Type | info:eu-repo/semantics/masterThesis |
| Rights | info:eu-repo/semantics/restrictedAccess |
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