Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Fishfauna from the lowland Mureș river (Romania) and the Floodplain Natural Park area (Western Romania).

Abstract

The lowland Mureș river in Romania is approximately 120 km in length. More than 80 km are comprised of the Mureș Floodplain Natural Park that was established since the year 2007. This river stretch has different biotopes with lotic or lentic semblances with very characteristic and diverse fish fauna. Along the lowland main stream a system of canals, marshes and pools are connected. The results of repeated ichthyological surveys carried out during the years 1998-2001 and 2004 revealed that 48 fish species live in this river sector and the other 2 species have an uncertain presence. Most of the species from the river mainstream maintained their former abundance (24 species), while the other 16 increased in abundance. The burbot Lota lota and Zingel zingel became frequent in the lowland Mureș, probably as consequence of their population renewal. The number of fish species that have undergone regression is less (4 species) and the exotic species present here are limited to 8 species. The major threatening factors in the lowland Mureș include the mineral aggregate extractions directly from the riverbed and the waste water spillage. Subsequently, shortening the meanders and backwaters has a negative impact on these fish populations.