Extremely shallow spawning of perch (Perca fluviatilis L.): the roles of sheltered bays, dense semi-terrestrial vegetation and low visibility in deeper water

0385527 - BC 2013 RIV FR eng J - Článek v odborném periodiku
Čech, Martin - Peterka, Jiří - Říha, Milan - Vejřík, Lukáš - Jůza, Tomáš - Kratochvíl, Michal - Draštík, Vladislav - Muška, Milan - Znachor, Petr - Kubečka, Jan
Extremely shallow spawning of perch (Perca fluviatilis L.): the roles of sheltered bays, dense semi-terrestrial vegetation and low visibility in deeper water.
Knowledge and Management of Aquatic Ecosystems. Roč. 406, December (2012), 09p1-09p12. ISSN 1961-9502. E-ISSN 1961-9502
Grant CEP: GA ČR(CZ) GA206/06/1371; GA ČR(CZ) GP206/09/P266; GA MZe(CZ) QH81046
Institucionální podpora: RVO:60077344
Klíčová slova: Římov Reservoir * Chabařovice Lake * SCUBA diving * Reed Canarygrass Phalaris arudinacea * Goat Willow Salix caprea * egg strands
Kód oboru RIV: EG - Zoologie
Impakt faktor: 0.467, rok: 2012

The roles of wind protected bays, presence of littoral vegetation and light attenuation in the water column on spawning site selection and depth of egg strands deposition by perch Perca fluviatilis was studied in Římov Reservoir, Czech Republic, in the years 2007 and 2011 using boat observation and SCUBA divers. The data were compared with results from Chabařovice Lake, Czech Republic, where similar monitoring took place in 2007-2010 and 2012. In shallow water of Římov Reservoir, the density of egg strands was significantly higher in grass bays compared to rocky bays and in the main reservoir. Most egg strands were deposited in water less than 0.5 m deep on reed canarygrass Phalaris arudinacea. In year when the littoral vegetation was absent perch were forced to spawn significantly deeper on various types of woody structures. In Římov Reservoir, which is less vulnerable to wind, 91.1% of egg strands were spawned in water less than 3 m deep. In contrast, in the wind exposed Chabařovice Lake, even in the presence of littoral vegetation, 90.5% of egg strands were found at depths greater than 3 m. In Chabařovice Lake, the light penetrated to three times greater depth compared to Římov Reservoir and, similarly, the depth limit to which 95% of egg strands were spawned was three times greater in this lake compared to Římov Reservoir. This study is the first contribution showing the role of water transparency in controlling the depth distribution of perch egg strands in lakes and reservoirs.
Trvalý link: http://hdl.handle.net/11104/0214735