As already mentioned in the ‘Introduction’, these authors found both gravid females and larvae and juveniles in Kiel Fjord and in the eastern Kiel Canal, where the salinity is 12–30 PSU.

It is assumed that this population may be a donor area for the crabs found in the southern and eastern Baltic Sea. Based on these studies it might be assumed that females of E. sinensis follow a regular life cycle in the southern Baltic Sea, reaching sexual maturity, copulating and PS-341 cell line placing eggs on pleopods. But it is not clear whether the eggs undergo complete development and hence, whether the Chinese mitten crab is able to reproduce in the southern Baltic Sea. On the one hand there is no evidence of any larval stages, but this may be due to the lack of appropriate zooplankton studies (i.e. the use of inappropriate sampling gear at the wrong time and/or place). On the other hand, the latest studies of Otto & Brandis (2011) have shown that there is probably a chance of the larval cycle reaching completion in the Baltic Sea, because E. sinensis larvae can live and develop in extreme conditions as far as their physiology is concerned. Moreover, CHIR-99021 non-native species evolve quickly and are able, even in the short term, to adapt to new conditions, which may significantly differ from those in their native regions ( Sax & Gaines 2003). A spectacular example is the calanoid copepod Eurytemora affinis. During

one century the evolution of ionic regulation in this Atlantic species has enabled it to colonise fresh waters in North America ( Lee et al. 2007, Lee & Gelembiuk 2008). E. sinensis has inhabited the southern Baltic Sea for almost 100 years and maybe this species too, with its high phenotypic plasticity, has evolved mechanisms which in the age of global warming enable larvae to tolerate less saline waters. To confirm these assumptions more detailed studies are required: in the environment (a search for larvae) and in the laboratory (on selection response). “
“Baltic herring (Clupea harengus membras L.) is one of

the dominant fish species in the Baltic Sea ( Rajasilta et al. 2006). This makes it not only an important resource for commercial fishing ( Cardinale & Arrhenius 2000) but also an important part of the pelagic ecosystem. MG-132 mouse Baltic herring spawn throughout the Baltic, and as a result of the strong environmental gradients different populations have unique biological and spawning characteristics ( Geffen 2009). In the period from 1991 to 2010 Baltic herring catches in the Lithuanian economic zone varied from 0.7 to 6.5 thousand tons per year, making it the most important fish resource (Fedotova 2010). However, Baltic herring stocks are constantly changing, owing to anthropogenic impact and natural hydrological regime shifts in the Baltic Sea and the North Atlantic region (ICES 2008), indicating that careful management is needed for this species.