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Akoglu E. Ecological indicators reveal historical regime shifts in the Black Sea ecosystem. PeerJ 2023; 11:e15649. [PMID: 37456881 PMCID: PMC10348305 DOI: 10.7717/peerj.15649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 06/06/2023] [Indexed: 07/18/2023] Open
Abstract
Background The Black Sea is one of the most anthropogenically disturbed marine ecosystems in the world because of introduced species, fisheries overexploitation, nutrient enrichment via pollution through river discharge, and the impacts of climate change. It has undergone significant ecosystem transformations since the 1960s. The infamous anchovy and alien warty comb jelly Mnemiopsis leidyi shift that occurred in 1989 is the most well-known example of the drastic extent of anthropogenic disturbance in the Black Sea. Although a vast body of literature exists on the Black Sea ecosystem, a holistic look at the multidecadal changes in the Black Sea ecosystem using an ecosystem- and ecology-based approach is still lacking. Hence, this work is dedicated to filling this gap. Methods First, a dynamic food web model of the Black Sea extending from 1960 to 1999 was established and validated against time-series data. Next, an ecological network analysis was performed to calculate the time series of synthetic ecological indicators, and a regime shift analysis was performed on the time series of indicators. Results The model successfully replicated the regime shifts observed in the Black Sea. The results showed that the Black Sea ecosystem experienced four regime shifts and was reorganized due to effects instigated by overfishing in the 1960s, eutrophication and establishment of trophic dead-end organisms in the 1970s, and overfishing and intensifying interspecies trophic competition by the overpopulation of some r-selected organisms (i.e., jellyfish species) in the 1980s. Overall, these changes acted concomitantly to erode the structure and function of the ecosystem by manipulating the food web to reorganize itself through the introduction and selective removal of organisms and eutrophication. Basin-wide, cross-national management efforts, especially with regard to pollution and fisheries, could have prevented the undesirable changes observed in the Black Sea ecosystem and should be immediately employed for management practices in the basin to prevent such drastic ecosystem fluctuations in the future.
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Novotny A, Serandour B, Kortsch S, Gauzens B, Jan KMG, Winder M. DNA metabarcoding highlights cyanobacteria as the main source of primary production in a pelagic food web model. SCIENCE ADVANCES 2023; 9:eadg1096. [PMID: 37126549 PMCID: PMC10132751 DOI: 10.1126/sciadv.adg1096] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Models that estimate rates of energy flow in complex food webs often fail to account for species-specific prey selectivity of diverse consumer guilds. While DNA metabarcoding is increasingly used for dietary studies, methodological biases have limited its application for food web modeling. Here, we used data from dietary metabarcoding studies of zooplankton to calculate prey selectivity indices and assess energy fluxes in a pelagic resource-consumer network. We show that food web dynamics are influenced by prey selectivity and temporal match-mismatch in growth cycles and that cyanobacteria are the main source of primary production in the investigated coastal pelagic food web. The latter challenges the common assumption that cyanobacteria are not supporting food web productivity, a result that is increasingly relevant as global warming promotes cyanobacteria dominance. While this study provides a method for how DNA metabarcoding can be used to quantify energy fluxes in a marine food web, the approach presented here can easily be extended to other ecosystems.
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Affiliation(s)
- Andreas Novotny
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden
| | - Baptiste Serandour
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden
| | - Susanne Kortsch
- Spatial Foodweb Ecology Group, Department of Agricultural Sciences, University of Helsinki, Helsinki, Finland
- Environmental and Marine Biology, Åbo Akademi University, Turku 20500, Finland
| | - Benoit Gauzens
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
- Institute of Biodiversity, Friedrich Schiller University, Jena, Germany
| | - Kinlan M G Jan
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden
| | - Monika Winder
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden
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Stock A, Murray CC, Gregr EJ, Steenbeek J, Woodburn E, Micheli F, Christensen V, Chan KMA. Exploring multiple stressor effects with Ecopath, Ecosim, and Ecospace: Research designs, modeling techniques, and future directions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 869:161719. [PMID: 36693571 DOI: 10.1016/j.scitotenv.2023.161719] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 01/04/2023] [Accepted: 01/15/2023] [Indexed: 06/17/2023]
Abstract
Understanding the cumulative effects of multiple stressors is a research priority in environmental science. Ecological models are a key component of tackling this challenge because they can simulate interactions between the components of an ecosystem. Here, we ask, how has the popular modeling platform Ecopath with Ecosim (EwE) been used to model human impacts related to climate change, land and sea use, pollution, and invasive species? We conducted a literature review encompassing 166 studies covering stressors other than fishing mostly in aquatic ecosystems. The most modeled stressors were physical climate change (60 studies), species introductions (22), habitat loss (21), and eutrophication (20), using a range of modeling techniques. Despite this comprehensive coverage, we identified four gaps that must be filled to harness the potential of EwE for studying multiple stressor effects. First, only 12% of studies investigated three or more stressors, with most studies focusing on single stressors. Furthermore, many studies modeled only one of many pathways through which each stressor is known to affect ecosystems. Second, various methods have been applied to define environmental response functions representing the effects of single stressors on species groups. These functions can have a large effect on the simulated ecological changes, but best practices for deriving them are yet to emerge. Third, human dimensions of environmental change - except for fisheries - were rarely considered. Fourth, only 3% of studies used statistical research designs that allow attribution of simulated ecosystem changes to stressors' direct effects and interactions, such as factorial (computational) experiments. None made full use of the statistical possibilities that arise when simulations can be repeated many times with controlled changes to the inputs. We argue that all four gaps are feasibly filled by integrating ecological modeling with advances in other subfields of environmental science and in computational statistics.
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Affiliation(s)
- A Stock
- Institute for Resources, Environment and Sustainability, University of British Columbia, AERL Building, 429-2202 Main Mall, Vancouver V6T 1Z4, BC, Canada.
| | - C C Murray
- Fisheries and Oceans Canada, Institute of Ocean Sciences, 9860 West Saanich Road, Sidney, BC V8L 5T5, Canada
| | - E J Gregr
- Institute for Resources, Environment and Sustainability, University of British Columbia, AERL Building, 429-2202 Main Mall, Vancouver V6T 1Z4, BC, Canada; SciTech Environmental Consulting, Vancouver, BC, Canada
| | - J Steenbeek
- Ecopath International Initiative (EII) Research Association, Barcelona, Spain
| | - E Woodburn
- Institute for Resources, Environment and Sustainability, University of British Columbia, AERL Building, 429-2202 Main Mall, Vancouver V6T 1Z4, BC, Canada
| | - F Micheli
- Hopkins Marine Station, Oceans Department, Stanford University, Pacific Grove, CA 93950, USA; Stanford Center for Ocean Solutions, Pacific Grove, CA 93950, USA
| | - V Christensen
- Ecopath International Initiative (EII) Research Association, Barcelona, Spain; Institute for the Oceans and Fisheries, University of British Columbia, Vancouver, BC, Canada
| | - K M A Chan
- Institute for Resources, Environment and Sustainability, University of British Columbia, AERL Building, 429-2202 Main Mall, Vancouver V6T 1Z4, BC, Canada; Institute for the Oceans and Fisheries, University of British Columbia, Vancouver, BC, Canada
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4
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Korpinen S, Uusitalo L, Nordström MC, Dierking J, Tomczak MT, Haldin J, Opitz S, Bonsdorff E, Neuenfeldt S. Food web assessments in the Baltic Sea: Models bridging the gap between indicators and policy needs. AMBIO 2022; 51:1687-1697. [PMID: 35092571 PMCID: PMC9110573 DOI: 10.1007/s13280-021-01692-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 10/22/2021] [Accepted: 12/13/2021] [Indexed: 06/14/2023]
Abstract
Ecosystem-based management requires understanding of food webs. Consequently, assessment of food web status is mandatory according to the European Union's Marine Strategy Framework Directive (MSFD) for EU Member States. However, how to best monitor and assess food webs in practise has proven a challenging question. Here, we review and assess the current status of food web indicators and food web models, and discuss whether the models can help addressing current shortcomings of indicator-based food web assessments, using the Baltic Sea as an example region. We show that although the MSFD food web assessment was designed to use food web indicators alone, they are currently poorly fit for the purpose, because they lack interconnectivity of trophic guilds. We then argue that the multiple food web models published for this region have a high potential to provide additional coherence to the definition of good environmental status, the evaluation of uncertainties, and estimates for unsampled indicator values, but we also identify current limitations that stand in the way of more formal implementation of this approach. We close with a discussion of which current models have the best capacity for this purpose in the Baltic Sea, and of the way forward towards the combination of measurable indicators and modelling approaches in food web assessments.
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Affiliation(s)
- Samuli Korpinen
- Finnish Environment Institute, Latokartanonkaari 11, 00790 Helsinki, Finland
| | - Laura Uusitalo
- Finnish Environment Institute, Latokartanonkaari 11, 00790 Helsinki, Finland
| | | | - Jan Dierking
- GEOMAR, Helmholtz Centre for Ocean Research Kiel, Duesternbrooker Weg 20, 24105 Kiel, Germany
| | | | - Jannica Haldin
- HELCOM Secretariat, Katajanokanlaituri 6B, 00160 Helsinki, Finland
| | - Silvia Opitz
- GEOMAR, Helmholtz Centre for Ocean Research Kiel, Duesternbrooker Weg 20, 24105 Kiel, Germany
| | | | - Stefan Neuenfeldt
- National Institute of Aquatic Resources, Technical University of Denmark (DTU Aqua), Kemitorvet, 2800 Kgs. Lyngby, Denmark
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Giralt Paradell O, Methion S, Rogan E, Díaz López B. Modelling ecosystem dynamics to assess the effect of coastal fisheries on cetacean species. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 285:112175. [PMID: 33607562 DOI: 10.1016/j.jenvman.2021.112175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 01/26/2021] [Accepted: 02/08/2021] [Indexed: 06/12/2023]
Abstract
The expansion of fisheries and its increased efficiency are causing severe detrimental impacts on marine species and ecosystems, that can be categorised into operational and ecological effects. While impacts directly caused by fishing activities have been extensively documented, it is difficult to set an empirical link between fisheries and changes in predator biomass and abundance. Therefore, exploring the functioning of ecosystems as a whole, the interactions between the different species within them and the impact of human activities, is key to understanding the ecological effects of fisheries on top predators and ecosystems, and to develop effective conservation measures, while ensuring a more sustainable exploitation of fishing resources. For instance, mass balance models, such as Ecopath with Ecosim, have proven to be a useful tool to develop more holistic fisheries management and conservation strategies. In this study, Ecopath with Ecosim was used to investigate the temporal dynamics of the Rías Baixas shelf ecosystem (North-West Spain) between 2005 and 2017. Additionally, nine 30-year forward projecting simulations covering the period 2018-2047 were developed to examine the effects of differing fisheries management strategies on common dolphins (Delphinus delphis), bottlenose dolphins (Tursiops truncatus) and harbour porpoises (Phocoena phocoena). Results from these models suggest that when intense fishing increases it poses a major threat to the conservation of these top predators in the area, by reducing the variety of their available prey and potentially enhancing competition amongst them. The study highlights the applicability of Ecopath with Ecosim to develop cetacean conservation measures and despite its small spatial scale, it provides a general framework that can be used to assess cetacean conservation in larger and impacted areas.
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Affiliation(s)
- Oriol Giralt Paradell
- The Bottlenose Dolphin Research Institute - BDRI. Av Beiramar 192, 36980, O Grove, Pontevedra, Spain; School of Biological, Earth and Environmental Sciences, University College Cork. Address: Distillery Fields, North Mall, Cork, T23 N73K, Ireland.
| | - Séverine Methion
- The Bottlenose Dolphin Research Institute - BDRI. Av Beiramar 192, 36980, O Grove, Pontevedra, Spain.
| | - Emer Rogan
- School of Biological, Earth and Environmental Sciences, University College Cork. Address: Distillery Fields, North Mall, Cork, T23 N73K, Ireland.
| | - Bruno Díaz López
- The Bottlenose Dolphin Research Institute - BDRI. Av Beiramar 192, 36980, O Grove, Pontevedra, Spain.
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Funk S, Frelat R, Möllmann C, Temming A, Krumme U. The forgotten feeding ground: patterns in seasonal and depth-specific food intake of adult cod Gadus morhua in the western Baltic Sea. JOURNAL OF FISH BIOLOGY 2021; 98:707-722. [PMID: 33200410 DOI: 10.1111/jfb.14615] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 11/05/2020] [Accepted: 11/15/2020] [Indexed: 06/11/2023]
Abstract
This study presents the diet composition of western Baltic cod Gadus morhua based on 3150 stomachs sampled year-round between 2016 and 2017 using angling, gillnetting and bottom trawling, which enhanced the spatio-temporal coverage of cod habitats. Cod diet composition in shallow areas (<20 m depth) was dominated by benthic invertebrate species, mainly the common shore crab Carcinus maneas. Compared to historic diet data from the 1960s and 1980s (limited to depth >20 m), the contribution of herring Clupea harengus decreased and round goby Neogobius melanostomus occurred as a new prey species. Statistical modelling revealed significant relationships between diet composition, catch depth, fish length and season. Generalized additive modelling identified a negative relationship between catch depth and stomach content weight, suggesting reduced food intake in winter when cod use deeper areas for spawning and during peak summer when cod tend to avoid high water temperatures. The results of this study highlight the importance of shallow coastal areas as major feeding habitats of adult cod in the western Baltic Sea, which were previously unknown because samples were restricted to deeper trawlable areas. The results strongly suggest that historic stomach analyses overestimated the role of forage fish and underestimated the role of invertebrate prey. Eventually, this study shows the importance of a comprehensive habitat coverage for unbiased stomach sampling programmes to provide a more reliable estimation of top predator diet, a key information for food web analyses and multispecies models.
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Affiliation(s)
- Steffen Funk
- Department of Biology, Institute of Marine Ecosystem and Fishery Science, Centre for Earth System Research and Sustainability (CEN), University of Hamburg, Hamburg, Germany
| | - Romain Frelat
- Department of Biology, Institute of Marine Ecosystem and Fishery Science, Centre for Earth System Research and Sustainability (CEN), University of Hamburg, Hamburg, Germany
- Aquaculture and Fisheries Group, Wageningen University, Wageningen, The Netherlands
| | - Christian Möllmann
- Department of Biology, Institute of Marine Ecosystem and Fishery Science, Centre for Earth System Research and Sustainability (CEN), University of Hamburg, Hamburg, Germany
| | - Axel Temming
- Department of Biology, Institute of Marine Ecosystem and Fishery Science, Centre for Earth System Research and Sustainability (CEN), University of Hamburg, Hamburg, Germany
| | - Uwe Krumme
- Thünen Institute of Baltic Sea Fisheries, Rostock, Germany
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Kadin M, Frederiksen M, Niiranen S, Converse SJ. Linking demographic and food-web models to understand management trade-offs. Ecol Evol 2019; 9:8587-8600. [PMID: 31410264 PMCID: PMC6686646 DOI: 10.1002/ece3.5385] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 05/13/2019] [Accepted: 05/18/2019] [Indexed: 11/17/2022] Open
Abstract
Alternatives in ecosystem-based management often differ with respect to trade-offs between ecosystem values. Ecosystem or food-web models and demographic models are typically employed to evaluate alternatives, but the approaches are rarely integrated to uncover conflicts between values. We applied multistate models to a capture-recapture dataset on common guillemots Uria aalge breeding in the Baltic Sea to identify factors influencing survival. The estimated relationships were employed together with Ecopath-with-Ecosim food-web model simulations to project guillemot survival under six future scenarios incorporating climate change. The scenarios were based on management alternatives for eutrophication and cod fisheries, issues considered top priority for regional management, but without known direct effects on the guillemot population. Our demographic models identified prey quantity (abundance and biomass of sprat Sprattus sprattus) as the main factor influencing guillemot survival. Most scenarios resulted in projections of increased survival, in the near (2016-2040) and distant (2060-2085) future. However, in the scenario of reduced nutrient input and precautionary cod fishing, guillemot survival was projected to be lower in both future periods due to lower sprat stocks. Matrix population models suggested a substantial decline of the guillemot population in the near future, 24% per 10 years, and a smaller reduction, 1.1% per 10 years, in the distant future. To date, many stakeholders and Baltic Sea governments have supported reduced nutrient input and precautionary cod fishing and implementation is underway. Negative effects on nonfocal species have previously not been uncovered, but our results show that the scenario is likely to negatively impact the guillemot population. Linking model results allowed identifying trade-offs associated with management alternatives. This information is critical to thorough evaluation by decision-makers, but not easily obtained by food-web models or demographic models in isolation. Appropriate datasets are often available, making it feasible to apply a linked approach for better-informed decisions in ecosystem-based management.
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Affiliation(s)
- Martina Kadin
- School of Aquatic and Fishery SciencesUniversity of WashingtonSeattleWashingtonUSA
- Swedish Museum of Natural HistoryStockholmSweden
| | | | - Susa Niiranen
- Stockholm Resilience CentreStockholm UniversityStockholmSweden
| | - Sarah J. Converse
- U.S. Geological SurveyWashington Cooperative Fish and Wildlife Research Unit, School of Environmental and Forest Sciences (SEFS) and School of Aquatic and Fishery Sciences (SAFS)University of WashingtonSeattleWashingtonUSA
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8
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Jagers SC, Matti S, Crépin AS, Langlet D, Havenhand JN, Troell M, Filipsson HL, Galaz VR, Anderson LG. Societal causes of, and responses to, ocean acidification. AMBIO 2019; 48:816-830. [PMID: 30430407 PMCID: PMC6541573 DOI: 10.1007/s13280-018-1103-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 05/11/2018] [Accepted: 09/11/2018] [Indexed: 05/19/2023]
Abstract
Major climate and ecological changes affect the world's oceans leading to a number of responses including increasing water temperatures, changing weather patterns, shrinking ice-sheets, temperature-driven shifts in marine species ranges, biodiversity loss and bleaching of coral reefs. In addition, ocean pH is falling, a process known as ocean acidification (OA). The root cause of OA lies in human policies and behaviours driving society's dependence on fossil fuels, resulting in elevated CO2 concentrations in the atmosphere. In this review, we detail the state of knowledge of the causes of, and potential responses to, OA with particular focus on Swedish coastal seas. We also discuss present knowledge gaps and implementation needs.
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Affiliation(s)
- Sverker C. Jagers
- Department of Political Science, University of Gothenburg, Box 711, Sprängkullsgatan 19, 405 30 Göteborg, Sweden
| | - Simon Matti
- Department of Political Science, University of Gothenburg, Box 711, Sprängkullsgatan 19, 405 30 Göteborg, Sweden
- Political Science Unit, Luleå University of Technology, 97187 Luleå, Sweden
| | - Anne-Sophie Crépin
- The Beijer Institute of Ecological Economics, The Royal Swedish Academy of Science, Lilla Frescativägen 4, 104 05 Stockholm, Sweden
- Stockholm Resilience Centre, Stockholm University, Kräftriket 2 B, 10691 Stockholm, Sweden
| | - David Langlet
- Department of Law, University of Gothenburg, Box 650, 40530 Göteborg, Sweden
| | - Jonathan N. Havenhand
- Department of Marine Sciences-Tjärnö, Tjärnö Marine Laboratory, University of Gothenburg, 45296 Strömstad, Sweden
| | - Max Troell
- The Beijer Institute of Ecological Economics, The Royal Swedish Academy of Science, Lilla Frescativägen 4, 104 05 Stockholm, Sweden
- Stockholm Resilience Centre, Stockholm University, Kräftriket 2 B, 10691 Stockholm, Sweden
| | | | - Victor R. Galaz
- Stockholm Resilience Centre, Stockholm University, Kräftriket 2 B, 10691 Stockholm, Sweden
| | - Leif G. Anderson
- Department of Marine Sciences, University of Gothenburg, Box 461, 40530 Göteborg, Sweden
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Costalago D, Bauer B, Tomczak MT, Lundström K, Winder M. The necessity of a holistic approach when managing marine mammal-fisheries interactions: Environment and fisheries impact are stronger than seal predation. AMBIO 2019; 48:552-564. [PMID: 30536186 PMCID: PMC6486897 DOI: 10.1007/s13280-018-1131-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 07/07/2018] [Accepted: 11/13/2018] [Indexed: 06/09/2023]
Abstract
Seal populations are recovering in many regions around the world and, consequently, they are increasingly interacting with fisheries. We used an Ecopath with Ecosim model for the offshore Central Baltic Sea to investigate the interactions between the changes in fish stocks and grey seal (Halichoerus grypus) population under different fishing and environmental scenarios for the twenty-first century. The assumed climate, eutrophication and cod (Gadus morhua) fisheries scenarios modified seal predation impacts on fish. Fish biomass and catches are more affected by fishing mortality and the environment than by seal predation. Our results highlight that the impacts of the increasing seal population on lower trophic levels are complex; thus, we emphasize the need to consider a range of possible ecosystem contexts when evaluating potential impacts of top predators. Finally, we suggest that an increasing seal population is not likely to hinder the preservation of the main Baltic fish stocks.
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Affiliation(s)
- David Costalago
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Campus Frescati, Svante Arrhenius väg 20 F, 106 91 Stockholm, Sweden
- Institute for the Oceans and Fisheries, University of British Columbia, UBC-AERL, 2202 Main Mall, Vancouver, BC V6T 1Z4 Canada
| | - Barbara Bauer
- Baltic Sea Centre, Stockholm University, Campus Frescati, Svante Arrhenius väg 20 F, 106 91 Stockholm, Sweden
| | - Maciej T. Tomczak
- Baltic Sea Centre, Stockholm University, Campus Frescati, Svante Arrhenius väg 20 F, 106 91 Stockholm, Sweden
| | - Karl Lundström
- Department of Aquatic Resources, Swedish University of Agricultural Sciences (SLU), Turistgatan 5, 45330 Lysekil, Sweden
| | - Monika Winder
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Campus Frescati, Svante Arrhenius väg 20 F, 106 91 Stockholm, Sweden
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Complementary methods assessing short and long-term prey of a marine top predator ‒ Application to the grey seal-fishery conflict in the Baltic Sea. PLoS One 2019; 14:e0208694. [PMID: 30601857 PMCID: PMC6314633 DOI: 10.1371/journal.pone.0208694] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 11/22/2018] [Indexed: 11/22/2022] Open
Abstract
The growing grey seal (Halichoerus grypus) population in the Baltic Sea has created conflicts with local fisheries, comparable to similar emerging problems worldwide. Adequate information on the foraging habits is a requirement for responsible management of the seal population. We investigated the applicability of available dietary assessment methods by comparing morphological analysis and DNA metabarcoding of gut contents (short-term diet; n = 129/125 seals, respectively), and tissue chemical markers i.e. fatty acid (FA) profiles of blubber and stable isotopes (SIs) of liver and muscle (mid- or long-term diet; n = 108 seals for the FA and SI markers). The methods provided complementary information. Short-term methods indicated prey species and revealed dietary differences between age groups and areas but for limited time period. In the central Baltic, herring was the main prey, while in the Gulf of Finland percid and cyprinid species together comprised the largest part of the diet. Perch was also an important prey in the western Baltic Proper. The DNA analysis provided firm identification of many prey species, which were neglected or identified only at species group level by morphological analysis. Liver SIs distinguished spatial foraging patterns and identified potentially migrated individuals, whereas blubber FAs distinguished individuals frequently utilizing certain types of prey. Tissue chemical markers of adult males suggested specialized feeding to certain areas and prey, which suggest that these individuals are especially prone to cause economic losses for fisheries. We recommend combined analyses of gut contents and tissue chemical markers as dietary monitoring methodology of aquatic top predators to support an optimal ecosystem-based management.
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Bossier S, Palacz AP, Nielsen JR, Christensen A, Hoff A, Maar M, Gislason H, Bastardie F, Gorton R, Fulton EA. The Baltic Sea Atlantis: An integrated end-to-end modelling framework evaluating ecosystem-wide effects of human-induced pressures. PLoS One 2018; 13:e0199168. [PMID: 30028849 PMCID: PMC6054375 DOI: 10.1371/journal.pone.0199168] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 06/01/2018] [Indexed: 12/03/2022] Open
Abstract
Achieving good environmental status in the Baltic Sea region requires decision support tools which are based on scientific knowledge across multiple disciplines. Such tools should integrate the complexity of the ecosystem and enable exploration of different natural and anthropogenic pressures such as climate change, eutrophication and fishing pressures in order to compare alternative management strategies. We present a new framework, with a Baltic implementation of the spatially-explicit end-to-end Atlantis ecosystem model linked to two external models, to explore the different pressures on the marine ecosystem. The HBM-ERGOM initializes the Atlantis model with high-resolution physical-chemical-biological and hydrodynamic information while the FISHRENT model analyses the fisheries economics of the output of commercial fish biomass for the Atlantis terminal projection year. The Baltic Atlantis model composes 29 sub-areas, 9 vertical layers and 30 biological functional groups. The balanced calibration provides realistic levels of biomass for, among others, known stock sizes of top predators and of key fish species. Furthermore, it gives realistic levels of phytoplankton biomass and shows reasonable diet compositions and geographical distribution patterns for the functional groups. By simulating several scenarios of nutrient load reductions on the ecosystem and testing sensitivity to different fishing pressures, we show that the model is sensitive to those changes and capable of evaluating the impacts on different trophic levels, fish stocks, and fisheries associated with changed benthic oxygen conditions. We conclude that the Baltic Atlantis forms an initial basis for strategic management evaluation suited for conducting medium to long term ecosystem assessments which are of importance for a number of pan-Baltic stakeholders in relation to anthropogenic pressures such as eutrophication, climate change and fishing pressure, as well as changed biological interactions between functional groups.
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Affiliation(s)
- Sieme Bossier
- National Institute of Aquatic Resources, Technical University of Denmark, Lyngby, Denmark
- * E-mail:
| | - Artur P. Palacz
- International Ocean Carbon Coordination Project, Institute of Oceanology of the Polish Academy of Sciences, Sopot, Poland
| | - J. Rasmus Nielsen
- National Institute of Aquatic Resources, Technical University of Denmark, Lyngby, Denmark
| | - Asbjørn Christensen
- National Institute of Aquatic Resources, Technical University of Denmark, Lyngby, Denmark
| | - Ayoe Hoff
- Department of Food and Resource Economics, Copenhagen University, Copenhagen, Denmark
| | - Marie Maar
- Department of Bioscience, Aarhus University, Roskilde, Denmark
| | - Henrik Gislason
- National Institute of Aquatic Resources, Technical University of Denmark, Lyngby, Denmark
| | - François Bastardie
- National Institute of Aquatic Resources, Technical University of Denmark, Lyngby, Denmark
| | | | - Elizabeth A. Fulton
- CSIRO Oceans & Atmosphere, Hobart, Australia
- Centre for Marine Socioecology, University of Tasmania, Battery Point, Tasmania, Australia
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13
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Karlsson K, Puiac S, Winder M. Life-history responses to changing temperature and salinity of the Baltic Sea copepod Eurytemora affinis. MARINE BIOLOGY 2018; 165:30. [PMID: 29391649 PMCID: PMC5773643 DOI: 10.1007/s00227-017-3279-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 12/22/2017] [Indexed: 06/03/2023]
Abstract
To understand the effects of predicted warming and changing salinity of marine ecosystems, it is important to have a good knowledge of species vulnerability and their capacity to adapt to environmental changes. In spring and autumn of 2014, we conducted common garden experiments to investigate how different populations of the copepod Eurytemora affinis from the Baltic Sea respond to varying temperatures and salinity conditions. Copepods were collected in the Stockholm archipelago, Bothnian Bay, and Gulf of Riga (latitude, longitude: 58°48.19', 17°37.52'; 65°10.14', 23°14.41'; 58°21.67', 24°30.83'). Using individuals with known family structure, we investigated within population variation of the reaction norm (genotype and salinity interaction) as a means to measure adaptive capacity. Our main finding was that low salinity has a detrimental effect on development time, the additive effects of high temperature and low salinity have a negative effect on survival, and their interaction has a negative effect on hatching success. We observed no variation in survival and development within populations, and all genotypes had similar reaction norms with higher survival and faster development in higher salinities. This suggests that there is no single genotype that performs better in low salinity or high salinity; instead, the best genotype in any given salinity is best in all salinities. Genotypes with fast development time also had higher survival compared to slow developing genotypes at all salinities. Our results suggest that E. affinis can tolerate close to freshwater conditions also in high temperatures, but with a significant reduction in fitness.
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Affiliation(s)
- Konrad Karlsson
- Department of Ecology, Environment, and Plant Sciences, Stockholm University, 10691 Stockholm, Sweden
| | - Simona Puiac
- Department of Ecology, Environment, and Plant Sciences, Stockholm University, 10691 Stockholm, Sweden
| | - Monika Winder
- Department of Ecology, Environment, and Plant Sciences, Stockholm University, 10691 Stockholm, Sweden
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14
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Griffiths JR, Kadin M, Nascimento FJA, Tamelander T, Törnroos A, Bonaglia S, Bonsdorff E, Brüchert V, Gårdmark A, Järnström M, Kotta J, Lindegren M, Nordström MC, Norkko A, Olsson J, Weigel B, Žydelis R, Blenckner T, Niiranen S, Winder M. The importance of benthic-pelagic coupling for marine ecosystem functioning in a changing world. GLOBAL CHANGE BIOLOGY 2017; 23:2179-2196. [PMID: 28132408 DOI: 10.1111/gcb.13642] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 12/22/2016] [Accepted: 01/06/2017] [Indexed: 05/12/2023]
Abstract
Benthic-pelagic coupling is manifested as the exchange of energy, mass, or nutrients between benthic and pelagic habitats. It plays a prominent role in aquatic ecosystems, and it is crucial to functions from nutrient cycling to energy transfer in food webs. Coastal and estuarine ecosystem structure and function are strongly affected by anthropogenic pressures; however, there are large gaps in our understanding of the responses of inorganic nutrient and organic matter fluxes between benthic habitats and the water column. We illustrate the varied nature of physical and biological benthic-pelagic coupling processes and their potential sensitivity to three anthropogenic pressures - climate change, nutrient loading, and fishing - using the Baltic Sea as a case study and summarize current knowledge on the exchange of inorganic nutrients and organic material between habitats. Traditionally measured benthic-pelagic coupling processes (e.g., nutrient exchange and sedimentation of organic material) are to some extent quantifiable, but the magnitude and variability of biological processes are rarely assessed, preventing quantitative comparisons. Changing oxygen conditions will continue to have widespread effects on the processes that govern inorganic and organic matter exchange among habitats while climate change and nutrient load reductions may have large effects on organic matter sedimentation. Many biological processes (predation, bioturbation) are expected to be sensitive to anthropogenic drivers, but the outcomes for ecosystem function are largely unknown. We emphasize how improved empirical and experimental understanding of benthic-pelagic coupling processes and their variability are necessary to inform models that can quantify the feedbacks among processes and ecosystem responses to a changing world.
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Affiliation(s)
- Jennifer R Griffiths
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 10691, Stockholm, Sweden
| | - Martina Kadin
- Stockholm Resilience Centre, Stockholm University, 10691, Stockholm, Sweden
| | - Francisco J A Nascimento
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 10691, Stockholm, Sweden
| | - Tobias Tamelander
- Tvärminne Zoological Station, University of Helsinki, J.A. Palméns väg 260, 10900, Hangö, Finland
| | - Anna Törnroos
- Environmental and Marine Biology, Åbo Akademi University, FI-20500, Turku, Finland
- Centre for Ocean Life, National Institute of Aquatic Resources, Technical University of Denmark, Kavalergården 6, 2920, Charlottenlund, Denmark
| | - Stefano Bonaglia
- Department of Geological Sciences, Stockholm University, 10691, Stockholm, Sweden
- Department of Geology, Lund University, 22362, Lund, Sweden
| | - Erik Bonsdorff
- Environmental and Marine Biology, Åbo Akademi University, FI-20500, Turku, Finland
| | - Volker Brüchert
- Department of Geological Sciences, Stockholm University, 10691, Stockholm, Sweden
| | - Anna Gårdmark
- Department of Aquatic Resources, Swedish University of Agricultural Sciences, Skolgatan 6, 74242, Öregrund, Sweden
| | - Marie Järnström
- Environmental and Marine Biology, Åbo Akademi University, FI-20500, Turku, Finland
| | - Jonne Kotta
- Estonian Marine Institute, University of Tartu, Mäealuse 14, 12618, Tallinn, Estonia
| | - Martin Lindegren
- Centre for Ocean Life, National Institute of Aquatic Resources, Technical University of Denmark, Kavalergården 6, 2920, Charlottenlund, Denmark
| | - Marie C Nordström
- Environmental and Marine Biology, Åbo Akademi University, FI-20500, Turku, Finland
| | - Alf Norkko
- Tvärminne Zoological Station, University of Helsinki, J.A. Palméns väg 260, 10900, Hangö, Finland
- Baltic Sea Centre, Stockholm University, Stockholm, 106 91, Sweden
| | - Jens Olsson
- Department of Aquatic Resources, Swedish University of Agricultural Sciences, Skolgatan 6, 74242, Öregrund, Sweden
| | - Benjamin Weigel
- Environmental and Marine Biology, Åbo Akademi University, FI-20500, Turku, Finland
| | | | - Thorsten Blenckner
- Stockholm Resilience Centre, Stockholm University, 10691, Stockholm, Sweden
| | - Susa Niiranen
- Stockholm Resilience Centre, Stockholm University, 10691, Stockholm, Sweden
| | - Monika Winder
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 10691, Stockholm, Sweden
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15
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Heymans JJ, Coll M, Link JS, Mackinson S, Steenbeek J, Walters C, Christensen V. Best practice in Ecopath with Ecosim food-web models for ecosystem-based management. Ecol Modell 2016. [DOI: 10.1016/j.ecolmodel.2015.12.007] [Citation(s) in RCA: 268] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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16
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Weigel B, Blenckner T, Bonsdorff E. Maintained functional diversity in benthic communities in spite of diverging functional identities. OIKOS 2016. [DOI: 10.1111/oik.02894] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Benjamin Weigel
- Environmental and Marine Biology, Åbo Akademi University; FI-20520 Turku Finland
| | - Thorsten Blenckner
- Stockholm Resilience Centre, Stockholm University; SE-10691 Stockholm Sweden
| | - Erik Bonsdorff
- Environmental and Marine Biology, Åbo Akademi University; FI-20520 Turku Finland
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17
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An empirical model of the Baltic Sea reveals the importance of social dynamics for ecological regime shifts. Proc Natl Acad Sci U S A 2015; 112:11120-5. [PMID: 26283344 DOI: 10.1073/pnas.1504954112] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Regime shifts triggered by human activities and environmental changes have led to significant ecological and socioeconomic consequences in marine and terrestrial ecosystems worldwide. Ecological processes and feedbacks associated with regime shifts have received considerable attention, but human individual and collective behavior is rarely treated as an integrated component of such shifts. Here, we used generalized modeling to develop a coupled social-ecological model that integrated rich social and ecological data to investigate the role of social dynamics in the 1980s Baltic Sea cod boom and collapse. We showed that psychological, economic, and regulatory aspects of fisher decision making, in addition to ecological interactions, contributed both to the temporary persistence of the cod boom and to its subsequent collapse. These features of the social-ecological system also would have limited the effectiveness of stronger fishery regulations. Our results provide quantitative, empirical evidence that incorporating social dynamics into models of natural resources is critical for understanding how resources can be managed sustainably. We also show that generalized modeling, which is well-suited to collaborative model development and does not require detailed specification of causal relationships between system variables, can help tackle the complexities involved in creating and analyzing social-ecological models.
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18
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Blenckner T, Llope M, Möllmann C, Voss R, Quaas MF, Casini M, Lindegren M, Folke C, Chr Stenseth N. Climate and fishing steer ecosystem regeneration to uncertain economic futures. Proc Biol Sci 2015; 282:20142809. [PMID: 25694626 PMCID: PMC4345453 DOI: 10.1098/rspb.2014.2809] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2014] [Accepted: 01/19/2015] [Indexed: 11/12/2022] Open
Abstract
Overfishing of large predatory fish populations has resulted in lasting restructurings of entire marine food webs worldwide, with serious socio-economic consequences. Fortunately, some degraded ecosystems show signs of recovery. A key challenge for ecosystem management is to anticipate the degree to which recovery is possible. By applying a statistical food-web model, using the Baltic Sea as a case study, we show that under current temperature and salinity conditions, complete recovery of this heavily altered ecosystem will be impossible. Instead, the ecosystem regenerates towards a new ecological baseline. This new baseline is characterized by lower and more variable biomass of cod, the commercially most important fish stock in the Baltic Sea, even under very low exploitation pressure. Furthermore, a socio-economic assessment shows that this signal is amplified at the level of societal costs, owing to increased uncertainty in biomass and reduced consumer surplus. Specifically, the combined economic losses amount to approximately 120 million € per year, which equals half of today's maximum economic yield for the Baltic cod fishery. Our analyses suggest that shifts in ecological and economic baselines can lead to higher economic uncertainty and costs for exploited ecosystems, in particular, under climate change.
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Affiliation(s)
- Thorsten Blenckner
- Stockholm Resilience Centre, Stockholm University, Kräftriket 2B, Stockholm 106 91, Sweden
| | - Marcos Llope
- Instituto Español de Oceanografía, Centro Oceanográfico de Cádiz, Puerto Pesquero, Muelle de Levante, Cadiz 11006, Spain Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, PO Box 1066 Blindern, Oslo 0316, Norway
| | - Christian Möllmann
- Institute of Hydrobiology and Fisheries Sciences, Center for Earth System Research and Sustainability, University of Hamburg, Grosse Elbstrasse 133, Hamburg 22767, Germany
| | - Rudi Voss
- Department of Economics, Christian Albrechts Universität zu Kiel, Olshausenstraße 40, Kiel 24118, Germany
| | - Martin F Quaas
- Department of Economics, Christian Albrechts Universität zu Kiel, Olshausenstraße 40, Kiel 24118, Germany
| | - Michele Casini
- Swedish University of Agricultural Sciences, Department of Aquatic Resources, Institute of Marine Research, Turistgatan 5, Lysekil 45330, Sweden
| | - Martin Lindegren
- Centre for Ocean Life, National Institute of Aquatic Resources, Technical University of Denmark, Charlottenlund Castle, Charlottenlund 2920, Denmark
| | - Carl Folke
- Stockholm Resilience Centre, Stockholm University, Kräftriket 2B, Stockholm 106 91, Sweden Beijer Institute of Ecological Economics, Royal Swedish Academy of Sciences, PO Box 50005, Stockholm 104 05, Sweden
| | - Nils Chr Stenseth
- Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, PO Box 1066 Blindern, Oslo 0316, Norway
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19
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van Leeuwen A, Huss M, Gårdmark A, de Roos AM. Ontogenetic specialism in predators with multiple niche shifts prevents predator population recovery and establishment. Ecology 2014. [DOI: 10.1890/13-0843.1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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20
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Meier HEM, Andersson HC, Arheimer B, Donnelly C, Eilola K, Gustafsson BG, Kotwicki L, Neset TS, Niiranen S, Piwowarczyk J, Savchuk OP, Schenk F, Węsławski JM, Zorita E. Ensemble modeling of the Baltic Sea ecosystem to provide scenarios for management. AMBIO 2014; 43:37-48. [PMID: 24414803 PMCID: PMC3888662 DOI: 10.1007/s13280-013-0475-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We present a multi-model ensemble study for the Baltic Sea, and investigate the combined impact of changing climate, external nutrient supply, and fisheries on the marine ecosystem. The applied regional climate system model contains state-of-the-art component models for the atmosphere, sea ice, ocean, land surface, terrestrial and marine biogeochemistry, and marine food-web. Time-dependent scenario simulations for the period 1960-2100 are performed and uncertainties of future projections are estimated. In addition, reconstructions since 1850 are carried out to evaluate the models sensitivity to external stressors on long time scales. Information from scenario simulations are used to support decision-makers and stakeholders and to raise awareness of climate change, environmental problems, and possible abatement strategies among the general public using geovisualization. It is concluded that the study results are relevant for the Baltic Sea Action Plan of the Helsinki Commission.
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Affiliation(s)
- H. E. Markus Meier
- Swedish Meteorological and Hydrological Institute, 601 76 Norrköping, Sweden
| | - Helén C. Andersson
- Swedish Meteorological and Hydrological Institute, 601 76 Norrköping, Sweden
| | - Berit Arheimer
- Swedish Meteorological and Hydrological Institute, 601 76 Norrköping, Sweden
| | - Chantal Donnelly
- Swedish Meteorological and Hydrological Institute, 601 76 Norrköping, Sweden
| | - Kari Eilola
- Swedish Meteorological and Hydrological Institute, 426 71 Västra Frölunda, Sweden
| | - Bo G. Gustafsson
- Baltic Nest Institute, Stockholm University, 106 91 Stockholm, Sweden
| | - Lech Kotwicki
- Department of Marine Ecology, Institute of Oceanology, Polish Academy of Sciences, 55 Powstancow Warszawy Street, 81-712 Sopot, Poland
| | - Tina-Simone Neset
- Centre for Climate Science and Policy Research, Department of Water and Environmental Studies, Linköping University, 601 74 Norrköping, Sweden
| | - Susa Niiranen
- Stockholm Resilience Centre, Stockholm University, 106 91 Stockholm, Sweden
| | - Joanna Piwowarczyk
- Department of Marine Ecology, Institute of Oceanology, Polish Academy of Sciences, 55 Powstancow Warszawy Street, 81-712 Sopot, Poland
| | - Oleg P. Savchuk
- Baltic Nest Institute, Stockholm University, 106 91 Stockholm, Sweden
| | - Frederik Schenk
- Institute of Coastal Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Str. 1, 21481 Geesthacht, Germany
| | - Jan Marcin Węsławski
- Department of Marine Ecology, Institute of Oceanology, Polish Academy of Sciences, 55 Powstancow Warszawy Street, 81-712 Sopot, Poland
| | - Eduardo Zorita
- Institute of Coastal Research, Helmholtz-Zentrum Geesthacht, 21502 Geeshacht, Germany
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21
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Lindegren M, Andersen KH, Casini M, Neuenfeldt S. A metacommunity perspective on source–sink dynamics and management: the Baltic Sea as a case study. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2014; 24:1820-1832. [PMID: 29210240 DOI: 10.1890/13-0566.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The degree to which metapopulation processes influence fish stock dynamics is a largely unresolved issue in marine science and management, especially for highly mobile species such as Atlantic cod (Gadus morhua) and herring (Clupea harengus). The Baltic Sea comprises a heterogeneous oceanographic environment that structures the spatial and temporal distribution of the dominant species cod, herring, and sprat (Sprattus sprattus). Despite local differences, the stocks are traditionally managed as homogeneous units. Here, we present a metacommunity-perspective on source–sink dynamics of Baltic Sea fish stocks by using a spatially disaggregated statistical food web model. The model is fitted to area-specific time series of multiple abiotic and biotic variables using state-space methods. Our analysis reveals pronounced net fluxes between areas, indicative of source–sink dynamics, as well as area-specific differences in species interactions (i.e., density dependence, competition, and predator–prey) and the degree of fishing and climate impact on survival and recruitment. Furthermore, model simulations show that decreasing exploitation pressure in the source area for cod (without reallocating fishing effort) produces an increase in neighboring sink habitats, but a decline of prey species in response to increased predation. Our approach provides valuable insight concerning metacommunity-structuring of marine fish and may serve as an important tool for implementing sustainable management strategies under the ecosystem approach to marine and fisheries management.
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22
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Niiranen S, Yletyinen J, Tomczak MT, Blenckner T, Hjerne O, Mackenzie BR, Müller-Karulis B, Neumann T, Meier HEM. Combined effects of global climate change and regional ecosystem drivers on an exploited marine food web. GLOBAL CHANGE BIOLOGY 2013; 19:3327-42. [PMID: 23818413 DOI: 10.1111/gcb.12309] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Accepted: 05/30/2013] [Indexed: 05/11/2023]
Abstract
Changes in climate, in combination with intensive exploitation of marine resources, have caused large-scale reorganizations in many of the world's marine ecosystems during the past decades. The Baltic Sea in Northern Europe is one of the systems most affected. In addition to being exposed to persistent eutrophication, intensive fishing, and one of the world's fastest rates of warming in the last two decades of the 20th century, accelerated climate change including atmospheric warming and changes in precipitation is projected for this region during the 21st century. Here, we used a new multimodel approach to project how the interaction of climate, nutrient loads, and cod fishing may affect the future of the open Central Baltic Sea food web. Regionally downscaled global climate scenarios were, in combination with three nutrient load scenarios, used to drive an ensemble of three regional biogeochemical models (BGMs). An Ecopath with Ecosim food web model was then forced with the BGM results from different nutrient-climate scenarios in combination with two different cod fishing scenarios. The results showed that regional management is likely to play a major role in determining the future of the Baltic Sea ecosystem. By the end of the 21st century, for example, the combination of intensive cod fishing and high nutrient loads projected a strongly eutrophicated and sprat-dominated ecosystem, whereas low cod fishing in combination with low nutrient loads resulted in a cod-dominated ecosystem with eutrophication levels close to present. Also, nonlinearities were observed in the sensitivity of different trophic groups to nutrient loads or fishing depending on the combination of the two. Finally, many climate variables and species biomasses were projected to levels unseen in the past. Hence, the risk for ecological surprises needs to be addressed, particularly when the results are discussed in the ecosystem-based management context.
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Affiliation(s)
- Susa Niiranen
- Stockholm Resilience Centre, Stockholm University, Stockholm, SE-106 91, Sweden; Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, SE-106 91, Sweden
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23
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Tomczak MT, Heymans JJ, Yletyinen J, Niiranen S, Otto SA, Blenckner T. Ecological network indicators of ecosystem status and change in the Baltic Sea. PLoS One 2013; 8:e75439. [PMID: 24116045 PMCID: PMC3792121 DOI: 10.1371/journal.pone.0075439] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 08/15/2013] [Indexed: 11/18/2022] Open
Abstract
Several marine ecosystems under anthropogenic pressure have experienced shifts from one ecological state to another. In the central Baltic Sea, the regime shift of the 1980s has been associated with food-web reorganization and redirection of energy flow pathways. These long-term dynamics from 1974 to 2006 have been simulated here using a food-web model forced by climate and fishing. Ecological network analysis was performed to calculate indices of ecosystem change. The model replicated the regime shift. The analyses of indicators suggested that the system’s resilience was higher prior to 1988 and lower thereafter. The ecosystem topology also changed from a web-like structure to a linearized food-web.
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Affiliation(s)
| | - Johanna J. Heymans
- Scottish Association for Marine Science, Scottish Marine Institute, Dunbeg, Oban, United Kingdom
| | - Johanna Yletyinen
- Nordic Centre for Research on Marine Ecosystems and Resources under Climate Change (NorMER), Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden
- Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden
| | - Susa Niiranen
- Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden
| | - Saskia A. Otto
- Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden
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24
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Gårdmark A, Lindegren M, Neuenfeldt S, Blenckner T, Heikinheimo O, Müller-Karulis B, Niiranen S, Tomczak MT, Aro E, Wikström A, Möllmann C. Biological ensemble modeling to evaluate potential futures of living marine resources. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2013; 23:742-54. [PMID: 23865226 DOI: 10.1890/12-0267.1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Natural resource management requires approaches to understand and handle sources of uncertainty in future responses of complex systems to human activities. Here we present one such approach, the "biological ensemble modeling approach," using the Eastern Baltic cod (Gadus morhua callarias) as an example. The core of the approach is to expose an ensemble of models with different ecological assumptions to climate forcing, using multiple realizations of each climate scenario. We simulated the long-term response of cod to future fishing and climate change in seven ecological models ranging from single-species to food web models. These models were analyzed using the "biological ensemble modeling approach" by which we (1) identified a key ecological mechanism explaining the differences in simulated cod responses between models, (2) disentangled the uncertainty caused by differences in ecological model assumptions from the statistical uncertainty of future climate, and (3) identified results common for the whole model ensemble. Species interactions greatly influenced the simulated response of cod to fishing and climate, as well as the degree to which the statistical uncertainty of climate trajectories carried through to uncertainty of cod responses. Models ignoring the feedback from prey on cod showed large interannual fluctuations in cod dynamics and were more sensitive to the underlying uncertainty of climate forcing than models accounting for such stabilizing predator-prey feedbacks. Yet in all models, intense fishing prevented recovery, and climate change further decreased the cod population. Our study demonstrates how the biological ensemble modeling approach makes it possible to evaluate the relative importance of different sources of uncertainty in future species responses, as well as to seek scientific conclusions and sustainable management solutions robust to uncertainty of food web processes in the face of climate change.
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Affiliation(s)
- Anna Gårdmark
- Swedish University of Agricultural Sciences, Department of Aquatic Resources, Institute of Coastal Research, Skolgatan 6, SE-742 42 Oregrund, Sweden.
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25
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van Leeuwen A, Huss M, Gårdmark A, Casini M, Vitale F, Hjelm J, Persson L, de Roos AM. Predators with multiple ontogenetic niche shifts have limited potential for population growth and top-down control of their prey. Am Nat 2013; 182:53-66. [PMID: 23778226 DOI: 10.1086/670614] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Catastrophic collapses of top predators have revealed trophic cascades and community structuring by top-down control. When populations fail to recover after a collapse, this may indicate alternative stable states in the system. Overfishing has caused several of the most compelling cases of these dynamics, and in particular Atlantic cod stocks exemplify such lack of recovery. Often, competition between prey species and juvenile predators is hypothesized to explain the lack of recovery of predator populations. The predator is then considered to compete with its prey for one resource when small and to subsequently shift to piscivory. Yet predator life history is often more complex than that, including multiple ontogenetic diet shifts. Here we show that no alternative stable states occur when predators in an intermediate life stage feed on an additional resource (exclusive to the predator) before switching to piscivory, because predation and competition between prey and predator do not simultaneously structure community dynamics. We find top-down control by the predator only when there is no feedback from predator foraging on the additional resource. Otherwise, the predator population dynamics are governed by a bottleneck in individual growth occurring in the intermediate life stage. Therefore, additional resources for predators may be beneficial or detrimental for predator population growth and strongly influence the potential for top-down community control.
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Affiliation(s)
- Anieke van Leeuwen
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94248, 1090 GE Amsterdam, The Netherlands.
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26
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Niiranen S, Blenckner T, Hjerne O, Tomczak MT. Uncertainties in a Baltic sea food-web model reveal challenges for future projections. AMBIO 2012; 41:613-25. [PMID: 22926883 PMCID: PMC3428477 DOI: 10.1007/s13280-012-0324-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Models that can project ecosystem dynamics under changing environmental conditions are in high demand. The application of such models, however, requires model validation together with analyses of model uncertainties, which are both often overlooked. We carried out a simplified model uncertainty and sensitivity analysis on an Ecopath with Ecosim food-web model of the Baltic Proper (BaltProWeb) and found the model sensitive to both variations in the input data of pre-identified key groups and environmental forcing. Model uncertainties grew particularly high in future climate change scenarios. For example, cod fishery recommendations that resulted in viable stocks in the original model failed after data uncertainties were introduced. In addition, addressing the trophic control dynamics produced by the food-web model proved as a useful tool for both model validation, and for studying the food-web function. These results indicate that presenting model uncertainties is necessary to alleviate ecological surprises in marine ecosystem management.
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Affiliation(s)
- Susa Niiranen
- />Baltic Nest Institute, Stockholm Resilience Centre, Stockholm University, 106 91 Stockholm, Sweden
| | - Thorsten Blenckner
- />Baltic Nest Institute, Stockholm Resilience Centre, Stockholm University, 106 91 Stockholm, Sweden
| | - Olle Hjerne
- />Department of Systems Ecology, Stockholm University, 106 91 Stockholm, Sweden
| | - Maciej T. Tomczak
- />Baltic Nest Institute, Stockholm Resilience Centre, Stockholm University, 106 91 Stockholm, Sweden
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27
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MacKenzie BR, Meier HEM, Lindegren M, Neuenfeldt S, Eero M, Blenckner T, Tomczak MT, Niiranen S. Impact of climate change on fish population dynamics in the Baltic sea: a dynamical downscaling investigation. AMBIO 2012; 41:626-36. [PMID: 22926884 PMCID: PMC3428476 DOI: 10.1007/s13280-012-0325-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Understanding how climate change, exploitation and eutrophication will affect populations and ecosystems of the Baltic Sea can be facilitated with models which realistically combine these forcings into common frameworks. Here, we evaluate sensitivity of fish recruitment and population dynamics to past and future environmental forcings provided by three ocean-biogeochemical models of the Baltic Sea. Modeled temperature explained nearly as much variability in reproductive success of sprat (Sprattus sprattus; Clupeidae) as measured temperatures during 1973-2005, and both the spawner biomass and the temperature have influenced recruitment for at least 50 years. The three Baltic Sea models estimate relatively similar developments (increases) in biomass and fishery yield during twenty-first century climate change (ca. 28 % range among models). However, this uncertainty is exceeded by the one associated with the fish population model, and by the source of global climate data used by regional models. Knowledge of processes and biases could reduce these uncertainties.
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Affiliation(s)
- Brian R. MacKenzie
- />Center for Macroecology, Evolution and Climate, National Institute for Aquatic Resources, Technical University of Denmark (DTU Aqua), Charlottenlund Castle, 2920 Charlottenlund, Denmark
| | - H. E. Markus Meier
- />Swedish Meteorological and Hydrological Institute, 60176 Norrköping, Sweden
| | - Martin Lindegren
- />National Institute for Aquatic Resources, Technical University of Denmark (DTU Aqua), Charlottenlund Castle, 2920 Charlottenlund, Denmark
| | - Stefan Neuenfeldt
- />National Institute for Aquatic Resources, Technical University of Denmark (DTU Aqua), Charlottenlund Castle, 2920 Charlottenlund, Denmark
| | - Margit Eero
- />National Institute for Aquatic Resources, Technical University of Denmark (DTU Aqua), Charlottenlund Castle, 2920 Charlottenlund, Denmark
| | - Thorsten Blenckner
- />Baltic Nest Institute, Stockholm Resilience Centre, Stockholm University, 106 91 Stockholm, Sweden
| | - Maciej T. Tomczak
- />Baltic Nest Institute, Stockholm Resilience Centre, Stockholm University, 106 91 Stockholm, Sweden
| | - Susa Niiranen
- />Baltic Nest Institute, Stockholm Resilience Centre, Stockholm University, 106 91 Stockholm, Sweden
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Havenhand JN. How will ocean acidification affect Baltic sea ecosystems? an assessment of plausible impacts on key functional groups. AMBIO 2012; 41:637-44. [PMID: 22926885 PMCID: PMC3428480 DOI: 10.1007/s13280-012-0326-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Increasing partial pressure of atmospheric CO₂ is causing ocean pH to fall-a process known as 'ocean acidification'. Scenario modeling suggests that ocean acidification in the Baltic Sea may cause a ≤ 3 times increase in acidity (reduction of 0.2-0.4 pH units) by the year 2100. The responses of most Baltic Sea organisms to ocean acidification are poorly understood. Available data suggest that most species and ecologically important groups in the Baltic Sea food web (phytoplankton, zooplankton, macrozoobenthos, cod and sprat) will be robust to the expected changes in pH. These conclusions come from (mostly) single-species and single-factor studies. Determining the emergent effects of ocean acidification on the ecosystem from such studies is problematic, yet very few studies have used multiple stressors and/or multiple trophic levels. There is an urgent need for more data from Baltic Sea populations, particularly from environmentally diverse regions and from controlled mesocosm experiments. In the absence of such information it is difficult to envision the likely effects of future ocean acidification on Baltic Sea species and ecosystems.
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Affiliation(s)
- Jonathan N Havenhand
- Department of Biological & Environmental Sciences - Tjärnö, University of Gothenburg, Sweden.
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