Metazoan parasites of Neogobius species, invasive fishes of the Slovak Danube River.
|Year of publication||2004|
|Type||Article in Proceedings|
|Conference||Abstract volume of the XI European Congress of Ichthyology|
|MU Faculty or unit|
|Description||During few recent years, the expansion of gobiid fish in waters of Slovak Danube River was registered. In present, Neogobius kessleri represents a dominant fish species in several localities of the Danube River basin in Slovak Republic. Other Neogobius fishes were also introduced in this region and their impacton natural fish assemblagesis increased due to their high population densities. Escapement from the effects of natural predators and parasites is a frequent explanation given for the success of invasive species. In this preliminary study, metazoan parasites of three Neogobius species were examined (N. kessleri, N. melanostomus, N. fluviatilis). Fish were collected from the Danube River (old and new channel), adjacent backwaters (N.k., resp. N.m.) and from the confluence of the Hron and Danube Rivers (N.f.) during 2002 and 2003. With the exception of two juvenile N. fluviatilis, all fish were parasitized. Glochidia of Anodonta anatina reached a maximum abundance (869 glochidia per fish) in all three fish species. Other ectoparasites (Monogenea, Copepoda) occured rarely. Trematoda were dominant endoparasites of N. kessleri and N. melanostomus, and Acanthocephala dominated in N. fluviatilis. In the case of endoparasites, Neogobius fishes were mostly intermediate (digenean, cestodes) or paratenic (cestodes, acanthocephalan, nematodes) hosts. he parasite species found are common parasites in the central Danube River region. No Neogobius-specific parasites known from their native populations were found.|