Home About Browse Search

Understanding the spatiotemporal dynamics of demersal fish species in the Baltic Sea

Orio, Alessandro (2019). Understanding the spatiotemporal dynamics of demersal fish species in the Baltic Sea. Diss. (sammanfattning/summary) Lysekil : Sveriges lantbruksuniv., Acta Universitatis Agriculturae Sueciae, 1652-6880 ; 2019:7
ISBN 978-91-7760-332-0
eISBN 978-91-7760-333-7
[Doctoral thesis]

[img] PDF


Species are not homogeneously distributed and the interdependencies between trophic interactions, environmental factors and anthropogenic forcing determine how their distribution changes over time. Hence taking into account both the spatial and temporal components of the dynamics of potentially interacting species is essential in management and conservation.

Cod and flounder are two key fish species of the Baltic Sea, both ecologically and commercially. However, their dynamics and interactions in the offshore demersal habitat have been largely neglected in the past. Therefore, the objective of this thesis was to obtain further knowledge on how their dynamics have changed in space and time in this region. This was achieved by investigating the long-term changes in the horizontal and vertical distribution of cod and flounder, and by quantifying their spatial overlap and potential interactions.

The results show that large changes have occurred in the demersal fish community of the Baltic Sea during the past four decades. Cod collapsed and contracted to the south, while flounder increased both in abundance and extent of distribution in the central Baltic. A contraction in the vertical distribution have been shown for both species from the early 1990s, possibly due to a combination of expanded areas of hypoxia in deep waters and an increase in predation risk in shallow waters. These changes have increased the spatial overlap between life-stages and species, which may have amplified the interaction strength between cod and flounder. The changes in predator-prey and competitive interactions between cod and flounder are hypothesised to have contributed to the low abundances of flounder during the “cod outburst” in the early 1980s, and to the low condition and feeding level of juvenile cod in the last decades.

These results are highly relevant both for fisheries management and marine spatial planning as they can be implemented in multispecies models or directly used to protect important areas and habitats. Moreover, the results could be used in stock assessments and management to take into account more realistically the dynamics of cod and flounder in the Baltic Sea.

Authors/Creators:Orio, Alessandro
Title:Understanding the spatiotemporal dynamics of demersal fish species in the Baltic Sea
Series Name/Journal:Acta Universitatis Agriculturae Sueciae
Year of publishing :2019
Number of Pages:64
IOrio, A., Florin, A.-B., Bergström, U., Šics, I., Baranova, T. and Casini, M. (2017). Modelling indices of abundance and size-based indicators of cod and flounder stocks in the Baltic Sea using newly standardized trawl survey data. ICES Journal of Marine Science, 74 (5), 1322-1333, doi:10.1093/icesjms/fsx005.
IIOrio, A., Bergström, U., Florin, A.-B., Lehmann, A., Šics, I. and Casini, M. (2019). Spatial contraction of demersal fish populations in a large marine ecosystem. Journal of Biogeography, doi:10.1111/jbi.13510.
IIIOrio, A., Bergström, U., Casini, M., Erlandsson, M., Eschbaum, R., Hüssy, K., Lehmann, A., Ložys, L., Ustups, D. and Florin, A.-B. (2017). Characterizing and predicting the distribution of Baltic Sea flounder (Platichthys flesus) during the spawning season. Journal of Sea Research, 126, 46-55, doi:10.1016/j.seares.2017.07.002.
IVOrio, A., Bergström, U., Florin, A.-B., Lehmann, A., Šics, I. and Casini, M. (2019). Long-term changes in spatial overlap between interacting demersal fish: a Baltic Sea case study. (manuscript)
Place of Publication:Lysekil
Publisher:Department of Aquatic Resources, Swedish University of Agricultural Sciences
ISBN for printed version:978-91-7760-332-0
ISBN for electronic version:978-91-7760-333-7
Publication Type:Doctoral thesis
Article category:Other scientific
Full Text Status:Public
Agris subject categories.:M Aquatic sciences and fisheries > M01 Fisheries and aquaculture - General aspects
M Aquatic sciences and fisheries > M40 Aquatic ecology
Subjects:(A) Swedish standard research categories 2011 > 4 Agricultural Sciences > 401 Agricultural, Forestry and Fisheries > Fish and Aquacultural Science
Keywords:Baltic Sea, cod, flounder, spatial distribution, species interaction
Permanent URL:
ID Code:15925
Faculty:NJ - Fakulteten för naturresurser och jordbruksvetenskap
Department:(NL, NJ) > Department of Aquatic Resources
Deposited By: SLUpub Connector
Deposited On:21 Feb 2019 11:01
Metadata Last Modified:01 Apr 2019 11:04

Repository Staff Only: item control page


Downloads per year (since September 2012)

View more statistics