Length-weight relationships (LWRs) are useful for calculating weight based on measurements of length. Here we provide LWRs 17 species fish from the rivers Vltava and Elbe in Czech Republic, Central Europe. The samples were collected by electrofishing May 2016 to August 2019. There far fewer riverine than lotic fish. All significant with r2 values ranging 0.99 European barbel (Barbus barbus) 0.9...

Lead (Pb), cadmium (Cd) and mercury (Hg) concentrations on liver and kidney of Sotalia fluviatilis (Cetacea: Delphinidae) stranded in the coast of Ceará, Brazil, were studied from 1996 to 1999. Pb levels were usually lower than the detection limit (0.1 microg/g). Concentrations of Cd were significantly higher in kidney than liver, averaging 0.8 microg/g. Mercury accumulation took place mainly i...

Freshwater ecosystems are increasingly impacted by alien invasive species which have the potential to alter various ecological interactions like predator-prey and host-parasite relationships. Here, we simultaneously examined predator-prey interactions and parasitization patterns of the highly invasive round goby (Neogobius melanostomus) in the rivers Rhine and Main in Germany. A total of 350 N....

  Neogobius caspius is an endemic species of the Caspian Sea which plays an important role in food chain as a predatory fish. The main aim of this study was to investigate selected feeding characteristics of Neogobius caspius in the south west coasts of the Caspian Sea. Monthly sampling was carried out using a bottom trawler at three stations (Astara, Anzali and Chabuksar) in three depths (0-5,...

The ecological impact of invasive species is likely to be modulated by human-induced alterations in habitats, which represents another driver biodiversity loss. We tested the effect soundscape degradation on predation round goby Neogobius melanostomus, one Europe’s “worst species”. For this, we compared relationship between per capita rate and prey density (i.e., functional response) presence o...