A1 Journal article (refereed)
Effects of top predator re-establishment and fishing on a simulated food web : Allometric Trophic Network model for Lake Oulujärvi (2024)

Kokkonen, E., Kuisma, M., Hyvärinen, P., Vainikka, A., Vuorio, K., Perälä, T., Härkönen, L. S., Estlander, S., & Kuparinen, A. (2024). Effects of top predator re-establishment and fishing on a simulated food web : Allometric Trophic Network model for Lake Oulujärvi. Ecological Modelling, 492, Article 110715. https://doi.org/10.1016/j.ecolmodel.2024.110715

JYU authors or editors

Kokkonen, Eevi
Kuisma, Mikael
Perälä, Tommi
Kuparinen, Anna

Publication details

All authors or editors: Kokkonen, Eevi; Kuisma, Mikael; Hyvärinen, Pekka; Vainikka, Anssi; Vuorio, Kristiina; Perälä, Tommi; Härkönen, Laura S.; Estlander, Satu; Kuparinen, Anna

Journal or series: Ecological Modelling

ISSN: 0304-3800

eISSN: 1872-7026

Publication year: 2024

Volume: 492

Article number: 110715

Publisher: Elsevier

Publication country: Netherlands

Publication language: English

DOI: https://doi.org/10.1016/j.ecolmodel.2024.110715

Publication open access: Openly available

Publication channel open access: Partially open access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/94357

Abstract

Fish communities face changes in environmental conditions and fishing that affects the abundances and structures of the populations. Before 1960s there were abundant stocks of both pikeperch (Stizostedion lucioperca) and whitefish (Coregonus lavaretus) in Lake Oulujärvi, but in 1960s–1970s the stock of pikeperch declined to very low levels while whitefish stock remained abundant. Due to massive re-introductions, pikeperch recovered since 1999 and is again common while whitefish stock has declined. To understand the ecosystem-level changes observed along the recovery of the pikeperch stock, we constructed a food web model capturing the two most recent states of pikeperch abundance in Lake Oulujärvi. We used Allometric Trophic Network (ATN) model to simulate the pelagic food web in the presence and absence of pikeperch and in the presence and absence of fishing. To parametrize ATN model based on body masses and food web interactions, we used data collections of fish cohort analyses, fish individuals, fish stomach contents, zooplankton, and phytoplankton in Lake Oulujärvi. Pikeperch decreased the biomasses of its planktivorous prey. Fishing truncated the age distribution of planktivorous fish. Pikeperch and fishing had synergistic negative effects on vendace (Coregonus albula) and smelt (Osmerus eperlanus) percentages of fish biomass, and antagonistic negative effect on whitefish and brown trout (Salmo trutta) percentages of fish biomass. Mysis relicta, Chaoborus flavicans, Leptodora and other predatory zooplankton, and Cyclopoida zooplankton guilds increased with fishing and pikeperch. Fishing, and pikeperch in the presence of fishing, increased biomass of Crustacean zooplankton guild. There were marked differences between the ATN model simulations and empirically observed time series of fish stock abundances suggesting that the observed changes are partially caused by environmental or fishing-related factors that were not included in the model.

Keywords: food webs; ecosystems (ecology); fishing; fishes; pike-perch; Coregonus lavaretus

Free keywords: species re-establishment; fishing mortality; food web; ecosystem change; top predator

Fields of science: