Wittmann 2011
Wittmann 2011
WITTMANN, K.J., 2011. Limnomysis benedeni [original text 29 pp., 10/06/2009 by K.J. WITTMANN]. In: CABI, Invasive Species Compendium (Beta), (CAB International, Wallingford, UK).
http://www.cabi.org/isc [21.10.2011]
Spread in the Danube system
In 1946, L. benedeni surprisingly appeared in the winter harbor of Budapest at Danube-km 1644 (first record for Hungary; Dudich, 1947; Woynárovich, 1955), this was almost 1200 km above the previously known, native distribution range. In 1950, specimens from the newly discovered populations near Danube-km 1623 were successfully transplanted to seven stations in Lake Balaton in order to enrich the basis of fish food (Woynárovich, 1955). During the following five decades, L. benedeni expanded its upstream distribution in 14 documented steps (Wittmann, 2007) up to the root of the Main-Danube-Channel in Kelheim at km 2410 in 1998. These expansions were probably not influenced by intentional transfers and yielded the first records for Slovakia (Brtek, 1953), Austria (Weish and Türkay, 1975), and Germany (Wittmann, 1995). The city of Kelheim marks the end of the navigable reach in the main course of this river, and remarkably this species did not expand further upstream in this course, so far documented up to 2008 (Wittmann and Ariani, 2009; additional sampling stations summarized in Wittmann, 2008). Most Danubian expansions are attributed to unintentional transport by ships (Wittmann, 1995, 2007; Reinhold and Tittizer, 1997). Molecular genetic data by Audzijonyte et al. (2009) suggest at least three westward invasion waves through the middle and upper reaches of the Danube from differentiated sources in the delta area.
Spread to and within the Rhine system
Probably shortly before 1997, L. benedeni transgressed the Main-Danube-Channel (officially opened 1992) where it was first recorded in 1998 by Reinhold and Tittizer (1998). In 1997-1998 it suddenly appeared in vast areas of the Rhine system probably by downstream expansion (drift) from this channel within the Main-Rhine system (first record for the Netherlands in 1997 by Kelleher et al., 1999). By subsequent upstream spread it appeared already in 1998 in the French reach (Wittmann and Ariani, 2000) and 2005 in the Swiss reach (Wittmann, 2007) of River Rhine. Further expansions within and from the Rhine system continued into tributaries and navigation canals in France (Wittmann and Ariani, 2009), Germany (Wittmann, 2007), and the Netherlands (Usseglio-Polatera and Beisel, 2003), yielding 2005 the first record for Belgium (Vercauteren and Wouters, 2008). A recent surprise in the Rhine system was the appearance in Lake Constance, marking the common borders of Austria, Germany, and Switzerland, in 2006 (Fritz et al., 2006; ANEBO, 2007). Most range expansions to, within, and from the Rhine system are attributed to the break-up of natural hydrographic barriers by construction of waterways in combination with ship traffic and passive drift, but also other modes of transfer may have played some role (Tittizer, 1997; Reinhold and Tittizer, 1997; Kelleher et al., 1999; Tittizer et al., 2000; Van der Velde et al., 2000; Wittmann and Ariani, 2000, 2009; Bij de Vaate et al., 2002; Dumont, 2006; Wittmann, 2007). Three major corridors were discussed for the unintentional anthropogenic spread of Ponto-Caspian aquatic species to western Europe (Schleuter et al., 1998; Bij de Vaate et al., 2002). Before the availability of genetic data it was not clear (Wittmann, 2007) whether the Limnomysis populations in NW Germany originate from invasions only along the southern corridor via Danube, Main-Danube-Channel, and Rhine or in part also from non-indigenous populations in tributaries of the Baltic. Molecular genetic data by Audzijonyte et al. (2009) finally indicated that western Europe was so far invaded only along the southern corridor.
Spread in eastern Europe
Starting in 1947 with a hydropower reservoir of the Dnieper River (Ukraine), a great number of water bodies in the former Soviet Union were intentionally stocked with L. benedeni in order to enrich the food supply for fish (Zhuravel, 1950; 1959; Ioffe, 1968; Grigorovich et al., 2002; Minchin and Rosenthal, 2002). Populations taken 1960 from the introduced population in the Dnieper hydropower reservoir and stocked in the Kaunas reservoir (Lithuania) spread along River Neman down to the Curonian Lagoon at the Baltic coast (Olenin and Leppäkoski, 1999; Arbaciauskas, 2002). Molecular genetic data by Audzijonyte et al. (2009) confirmed the supposed origin of the Curonian population from the Dnieper reservoir. This clade was so far not found anywhere in western Europe. Surprisingly, the Limnomysis taken 2004 in the Tsymliansk reservoir, this is above the native range of this species in River Don (Azov Sea drainage), belong genetically to a Caspian clade (Audzijonyte et al., 2006, 2009). Spread from populations in River Volga via the Volga-Don canal (finished 1951-1952) could plausibly explain this case. In 2003, the first finding for Poland was made in River Odra by Michels (2005). As shown in Fig. 2, these stations are almost equidistant from known populations in Lithuania and NW-Germany, therefore possible source areas of the Polish population cannot be judged unless genetic data are available. In 2007, L. benedeni appeared at three stations along River Pripyat (first records for Belarus by Semenchenko et al., 2007) where it may have spread via the central corridor from introduced populations in hydropower reservoirs of River Dnieper.
Europe; freshwater; rivers; range expansion; distribution; neobiota; environmental effects
Limnomysis benedeni