J 2019

When a river is affected by a reservoir: Trophic interactions and flexibility in feeding strategies of alpine bullhead (Cottus poecilopus) and European bullhead (Cottus gobio)

STEVOVE, Barbora, Miroslava BABELOVA, Danka HARUŠTIAKOVÁ and Vladimir KOVAC

Basic information

Original name

When a river is affected by a reservoir: Trophic interactions and flexibility in feeding strategies of alpine bullhead (Cottus poecilopus) and European bullhead (Cottus gobio)

Authors

STEVOVE, Barbora (703 Slovakia), Miroslava BABELOVA (703 Slovakia), Danka HARUŠTIAKOVÁ (703 Slovakia, guarantor, belonging to the institution) and Vladimir KOVAC (703 Slovakia)

Edition

Science of the Total Environment, Amsterdam, Elsevier Science, 2019, 0048-9697

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10511 Environmental sciences

Country of publisher

Netherlands

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

Impact factor

Impact factor: 6.551

RIV identification code

RIV/00216224:14310/19:00108987

Organization unit

Faculty of Science

UT WoS

000450551600025

Keywords in English

Montane river; Anthropogenic disturbance; Fish; Competition for food; Altitudinal distribution

Tags

International impact, Reviewed
Změněno: 13/3/2020 10:53, Mgr. Marie Šípková, DiS.

Abstract

V originále

The alpine bullhead and European bullhead are benthic fish species protected by law in several European countries. One of the problems of European rivers is the ever-increasing number of reservoirs, which has adverse impacts on aquatic ecosystems. Feeding ecology of both species evaluated separately has been a subject of several studies, however, none of the studies paid attention to feeding interactions between them. Thus, the aims of the study were to evaluate trophic interactions of the two bullhead species and to assess their ability to cope with environmental disturbances caused by a reservoir. The study area consisted of three sites on the river Cierny Vah (Slovakia) that differed from each other by the intensity of pressures posed by the reservoir. The two species were found to coexist at two sites below the reservoir, because the reservoir affected their distribution along the river. For alpine bullhead, chironomid, hydropsychid and baetid larvae were the most important prey items, whereas the diet spectrum of European bullhead contained hydropsychid, chironomid larvae and detritus. Differences in diet composition were found among sampling sites. Temporal variations in the diet composition demonstrated that alpine bullhead is a more flexible feeder than European bullhead. Being predominantly food generalists, both species were able to shift their feeding strategies towards specialization when exposed to environmental disturbances at the most affected site. The reservoir increased the diet overlap between the two species, and thus changed their trophic interactions. Both alpine bullhead and European bullhead managed to cope with environmental disturbances caused by the reservoir, however, in lower population densities. Moreover, the reduced diversity of resources increased the potential for trophic competition between them.