Seasonal dynamics in population characteristics of European bitterling Rhodeus amarus in a small lowland river

0358427 - ÚBO 2012 RIV GB eng J - Journal Article
Konečná, Markéta - Reichard, Martin
Seasonal dynamics in population characteristics of European bitterling Rhodeus amarus in a small lowland river.
Journal of Fish Biology. Roč. 78, č. 1 (2011), s. 227-239. ISSN 0022-1112. E-ISSN 1095-8649
R&D Projects: GA ČR GA206/09/1163
Institutional research plan: CEZ:AV0Z60930519
Keywords : bitterling * annual life cycle * ecophysiology * gonado-somatic index * lipid content * somatic condition
Subject RIV: EG - Zoology
Impact factor: 1.685, year: 2011

The seasonal dynamics of biological traits in a population of European bitterling Rhodeus amarus from a small river in central Europe (River Kyjovka) were investigated from April 2007 to March 2008. The reproductive season lasted from early April to mid-June, with a peak in late April when >50% of females possessed ripe eggs in their ovaries. The sex ratio was female-biased, with a higher bias following the peak in reproduction, suggesting higher mortality of males than females over the reproductive period. The population was effectively annual, with a major decrease in adult fish abundance at the end of the reproductive period. Highest relative lipid content and condition factor were observed in February, both decreasing with an increase in investment into gonads. Seasonal dynamics in somatic condition, relative lipid content and gonad mass, and their comparison with other R. amarus populations, suggest that the study population allocated a disproportionally high level of resources to reproduction.
Permanent Link: http://hdl.handle.net/11104/0196479