Disturbed fish fauna zonation as an indicator of large-scale human impact: A case study (2011-2012) of the large, lowland Warta River, Poland

• DOI: 10.1111/jai.13297
• Publication Date: 2017-02-28T06:18:28Z
• Authors: A. Kruk; M. Ciepłucha; G. Zięba; D. Błońska; L. Marszał; S. Tybulczuk; M. Tszydel; T. Penczak
• Keywords: Barbel; Ecotone; Grayling

The aim of the study was to assess whether ichthyofauna variability follows natural downstream gradient or degradation gradient, and bioindication potential fish zonation. conducted along entire length (795 km) lowland Warta River, Poland, wherein complexity ecotone zone availability hiding places for decreased downstream. catchment middle course carried a heavy load pollutants. In lower course, groynes were common, channel width exceeded 100 m mean discharge reached 210 m3/s. 2011–2012, single-run electrocatches lampreys performed at 73 sites, generally while wading long reaches both riverbanks (farthest upper depth ≤ 0.6 m) drifting in boat 500 riverbank stretch (in remaining river parts). An indicator species analysis allowed identification associated significantly with particular sections: one (a rheophil) source fragment (S1), seven (all rheophilic) (S2), three (S3), nine (including rheophils) (S4). On this basis, S1 classified as an impoverished grayling zone, S2 barbel S4 bream zone. Section S3 remained unclassified, its worst condition due to: (i) strong destabilizing upstream impact Jeziorsko dam reservoir, (ii) large amounts wastewater discharged from towns located area section (iii) lack unpolluted tributaries that could serve sources recolonizers. summary, human-modified assemblages followed which also reflected disturbed Consequently, confirms usefulness fauna zonation large-scale human impacts rivers.