Occurrence of exotic Russian sturgeons, Acipenser gueldenstaedtii Brandt et Ratzeburg, 1833 (Actinopterygii: Acipenseridae) in the Baltic Sea

Abstract

The occurrence of non-indigenous sturgeon species in the Baltic Sea is currently discussed in relation to plans for the re-establishing of the native A. sturio L. Introduced fishes must be considered competitors with regard to the utilisation of the habitat and food resources as well as to the potential risk of interference with the gene pool of the native species (Gessner et al. 1999). Therefore, any information on the biology of sturgeons acquired from open waters can be valuable. The first sturgeon was caught 800 m offshore in the Baltic Sea (Pomeranian Bay) near the village of UnieÊcie, on 17 December 2000. The fish weighed 549 g (before gutting) and its standard length was 38.2 cm (Fig.1). The second fish was caught 3 km offshore near the village of Gàski (Pomeranian coast between Ko∏obrzeg and Dar∏owo), on 20 October 2001. After gutting the fish weighed 1092 g and its standard length was 49.8 cm (Fig. 2).

Atlantic sturgeon Acipenser oxyrinchus and alien sturgeon species in Polish waters: can biometric analysis assist species discrimination and restoration?

“…In the sample, the number of scutes ranged from 21 to 30, with a mean of 25.22. The value was lower than that observed for A. oxyrinchus in the St Lawrence River in Canada (28.67) (Artiukhin, Vecsei, 1999) and considerably lower than found for exotic species occurring in Polish waters (Keszka, Heese, 2003;Keszka, Krzykawski, 2008;Keszka et al, 2009). Low variability of the countable characters in A. oxyrinchus specimens in the present study might be due to the limited number of broodstock used to produce stocking material as well as to an effect of artificial rearing conditions on juvenile fish, as had been noted in the case of other cultured sturgeon species (Ruban, Sokolov, 1986).…”

“…708/2007 concerning use of alien and locally absent species in aquaculture, a fourth source of exotic sturgeon introduction involves artificial breeding and release (Britton, Davis, 2006). The occurrence of non-native sturgeon species in German and Polish coastal waters and river estuaries has been growing since the beginning of the 1990s (Spratte, Rosenthal, 1996;Keszka, Stepanowska, 1997;Arndt et al, 2000Arndt et al, , 2002Keszka, Heese, 2003;Keszka et al, 2011). The presence of exotic sturgeon species was also observed in the Gironde River in France in 1999 after a period of storms that caused water levels to rise and resulted in the escape of several thousand A. baerii from fish farms.…”

Three new records of fishes and their parasite fauna from Pomeranian Bay, Baltic Sea

“…This could have happened, for example, when ponds were damaged during a severe thunderstorm, such as that reported in August 2017, when dozens of brook trout and sturgeon escaped into the Baltic Sea through the Pomeranian Grabowa River. Similarly, Keszka and Heese (2003) described two specimens of Acipenser gueldenstaedtii Brandt et Ratzeburg, 1833 in Pomeranian Bay that were likely escapees from fish farming facilities.…”

Theoretical Estimate of Energy Balance and Nutritional Needs of the Population of Russian Sturgeon Acipenser gueldenstaedtii in the Caspian Sea

“…In addition to the Caspian Sea Russian sturgeon (Acipenser gueldenstaedtii) population, this species is native to the Black Sea, Sea of Azov, entering all main rivers that empty into them (Sokolov and Berdicheskii, 1989;Kolman and Zarkua, 2002). The appearance of Russian sturgeon in the Baltic Sea basin may be explained by accidental escape of some young individuals from fish farms or purposely released by fishermen or aquarists (Keszka and Heese, 2003;Skora and Arciszewski, 2013). Russian sturgeon is one of the most important representatives of valuable commercial fish of the sturgeon family (Acipenseridae).…”