A1 Journal article (refereed)
The crayfish distribution, feeding plasticity, seasonal isotopic variation and trophic role across ontogeny and habitat in a canyon-shaped reservoir (2020)


Veselý, L., Ercoli, F., Ruokonen, T. J., Bláha, M., Kubec, J., Buřič, M., Hämäläinen, H., & Kouba, A. (2020). The crayfish distribution, feeding plasticity, seasonal isotopic variation and trophic role across ontogeny and habitat in a canyon-shaped reservoir. Aquatic Ecology, 54(4), 1169-1183. https://doi.org/10.1007/s10452-020-09801-w


JYU authors or editors


Publication details

All authors or editors: Veselý, Lukáš; Ercoli, Fabio; Ruokonen, Timo J.; Bláha, Martin; Kubec, Jan; Buřič, Miloš; Hämäläinen, Heikki; Kouba, Antonín

Journal or series: Aquatic Ecology

ISSN: 1386-2588

eISSN: 1573-5125

Publication year: 2020

Volume: 54

Issue number: 4

Pages range: 1169-1183

Publisher: Springer

Publication country: Netherlands

Publication language: English

DOI: https://doi.org/10.1007/s10452-020-09801-w

Publication open access: Not open

Publication channel open access:


Abstract

Man-made reservoirs are important freshwater ecosystems as they are globally common and share features of both standing and running waters. In streams and lakes, crayfish are an important component of freshwater ecosystems due to their habitat-modifying behaviour, substantial size, omnivorous feeding and often high abundance; however, their trophic role in reservoirs is not known. We evaluated the distribution and diet of noble crayfish (Astacus astacus) in the canyon-shaped, oligotrophic Nýrsko reservoir in West Bohemia region, Czech Republic. Using stable isotope analysis, we quantified the trophic level of all major components of the reservoir food web and investigated seasonal isotopic variation and how the trophic role of noble crayfish varied with habitat and ontogeny. Crayfish were an important food source for both predatory and omnivorous fish and consumed food sources from multiple trophic levels, including detritus, algae, zoobenthos and other crayfish. Throughout ontogeny, crayfish had similar levels of carnivory, but cannibalism was more prevalent in adult crayfish, while juveniles and sub-adults fed more on other zoobenthos. Moreover, crayfish had high feeding plasticity in time, as the relative importance of dominant food sources varied with season. Their feeding plasticity was especially evident in crayfish populations from different habitats, which adapted their feeding strategy to local resources. In addition, pelagic source usage increased with the depth as detritus and algae usage decreased. Proportion of females increased with the depth, while population density showed a unimodal response to the depth gradient. These findings indicate that crayfish are indeed ecologically important species with both direct and indirect roles in the trophic web of this reservoir ecosystem.


Keywords: aquatic ecosystems; food webs; reservoirs; Astacus astacus; isotope analysis; habitat; seasons

Free keywords: stable isotopes; reservoir; trophic chain; depth distribution; season; habitat; astacus astacus


Contributing organizations


Ministry reporting: Yes

Reporting Year: 2020

JUFO rating: 1


Last updated on 2021-07-07 at 21:33