Ichthyofauna of Wrocław - the Odra River, its tributaries and the selected city reservoirs

Abstract

Abstract:The ichthyofauna o f the O dra River, its m ajor tributaries (Oława, Widawa, Bystrzyca, Ślęza) and selected reservoirs (sand and clay pits, city park ponds, recreational reservoirs, city m oat) within the city o f W rocław is described on the basis o f data obtained in our ow n studies (electrofishing and net-catching), quality control catches o f the Polish Angling Association, analysis o f stocking registers, control and analysis o f angling inquiries and interviewing anglers in 1980-2010. Forty six fish and lamprey species were recorded: 42 in the Odra River, and 41 in its tributaries. Twenty eight species were recorded from the city reservoirs; they represented euryoecious and stagnophilous ecological groups. The study area holds nine species w hich are legally protected in Poland (Lampetra planeri, Acipenser oxirynchus, Gobi о albipinnatus, Rhodeus sericeus, Eupallasella percnurus, Cobitis taenia, Sabanejewia baltica (=aurata), Misgurnus fossilis, Barbatula barbatula) and five species regarded as endangered in the country {Barbus barbus, Vimba vimba, Chondrostoma nasus, Hucho hucho, Salmo salar). Eleven species occurring in the w ater courses and reservoirs o f W roclaw are protected within the EU Habitats Directive (92/43/EW G). Ten species introduced accidentally or on purpose occur in the city. Despite the high anthropopressure, including intensive angling, the W roclaw waters still hold diverse, and the O dra River itself -even rich -fish communities.

Diversity of Fish and Zoobenthic Communities in Lowland River Related to the Factors of Hydromorphological, River Continuum and Pollution Disturbances

“…The ichthyofauna was dominated by the gudgeon, and in the mostchanged sections almost exclusively this species was found, with only a small contribution of the stickelback and stone loach. This corresponds to the results of Witkowski et al (2007) who noted the dominance of the gudgeon in all sub-basins of the Oder, in particular those degraded anthropogenically. According to many authors, the occurrence of only a few psammophilic species is a phenomenon typical of small rivers, organically polluted (Marszał et al 2014, Mueller et al 2020, Penczak et al 1991, Prus et al 2016.…”

Genetic diversity and population structure of burbot Lota lota in Germany: Implications for conservation and management

“…In Europe, haplotypes of the BE clade have been detected only in Finland so far (Van Houdt et al, ), but were also found in the River Irtysh, China (Fang et al, ; Khrunyk, Koporikov, Bogdanov, & Borodin, ). An introduction of the H4a haplotype into the Odra could have occurred via stocking of burbot, which took place in the Odra basin in Poland from 1999 until 2010 (Witkowski et al, ). However, Van Houdt et al () found specimens of the EA clade only in the River Vistula in Poland, which is connected to the Odra via the Bydgoszcz Canal.…”

“…As burbot populations have declined during recent decades, it is important to maintain spawning grounds (Worthington et al, 2011) and to ascertain winter migration opportunities to allow for natural gene flow between populations and to preserve their adaptive potential. In recent decades, burbot have also been increasingly stocked into some German rivers, that is the Main, Ems, Vechte (Bosveld et al, 2015), the River Odra in Poland (Witkowski et al, 2012), the River Morava, Czech Republic (Adámek et al, 2013) and the rivers Grote Nete and Bosbeek in Belgium (Dillen et al, 2008). However, overall genetic structure of German burbot seems to be less affected by stocking than other commercial freshwater fishes such as brown trout Salmo trutta L. (Berrebi, Poteaux, Fissier, & Cattaneo-Berrebi, 2000;Vera, Martinez, & Bouza, 2017).…”

“…introduction of the H4a haplotype into the Odra could have occurred via stocking of burbot, which took place in the Odra basin in Poland from 1999 until 2010(Witkowski et al, 2012). However, Van Houdt et al (2005 found specimens of the EA clade only in the River Vistula in Poland, which is connected to the Odra via the Bydgoszcz Canal.…”