The osmoregulatory ability of the invasive species sunbleak Leucaspius delineatus and topmouth gudgeon Pseudorasbora parva at elevated salinities, and their likely dispersal via brackish waters

The European invasive species sunbleak Leucaspius delineatus and topmouth gudgeon Pseudorasbora parva, previously thought to be stenohaline freshwater fishes, were shown to tolerate salinities of 10.8 and 13.7 for up to 4 days. The increased plasma osmolality and ion concentrations, and decreased body water content, however, indicated that they are unable to hypo-osmoregulate. Therefore there is limited potential for these species to disperse into new river systems via brackish waters with a salinity > 13.7.