Search Results - "Hjelm, Joakim"

Multi-level trophic cascades in a heavily exploited open marine ecosystem by Casini, Michele, Lövgren, Johan, Hjelm, Joakim, Cardinale, Massimiliano, Molinero, Juan-Carlos, Kornilovs, Georgs

“…) population directly affected its main prey, the zooplanktivorous sprat (…”
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Trophic Cascades Promote Threshold-Like Shifts in Pelagic Marine Ecosystems by Casini, Michele, Hjelm, Joakim, Molinero, Juan-Carlos, Lövgren, Johan, Cardinale, Massimiliano, Bartolino, Valerio, Belgrano, Andrea, Kornilovs, Georgs, Paine, Robert T.

“…Fisheries can have a large impact on marine ecosystems, because the effects of removing large predatory fish may cascade down the food web. The implications of…”
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Eastern Baltic cod in distress: biological changes and challenges for stock assessment by Eero, Margit, Hjelm, Joakim, Behrens, Jane, Buchmann, Kurt, Cardinale, Massimiliano, Casini, Michele, Gasyukov, Pavel, Holmgren, Noel, Horbowy, Jan, Huessy, Karin, Kirkegaard, Eskild, Kornilovs, Georgs, Krumme, Uwe, Koster, Friedrich W, Oeberst, Rainer, Plikshs, Maris, Radtke, Krzysztof, Raid, Tiit, Schmidt, Jorn, Tomczak, Maciej T, Vinther, Morten, Zimmermann, Christopher, Storr-Paulsen, Marie

“…Abstract The eastern Baltic (EB) cod (Gadus morhua) stock was depleted and overexploited for decades until the mid-2000s, when fishing mortality rapidly…”
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Hypoxic areas, density-dependence and food limitation drive the body condition of a heavily exploited marine fish predator by Casini, Michele, Käll, Filip, Hansson, Martin, Plikshs, Maris, Baranova, Tatjana, Karlsson, Olle, Lundström, Karl, Neuenfeldt, Stefan, Gårdmark, Anna, Hjelm, Joakim

“…Investigating the factors regulating fish condition is crucial in ecology and the management of exploited fish populations. The body condition of cod (Gadus…”
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Inter-annual variation in herring, Clupea harengus, and sprat, Sprattus sprattus, condition in the central Baltic Sea: what gives the tune? by Casini, Michele, Cardinale, Massimiliano, Hjelm, Joakim

“…The Baltic Sea ecosystem has undergone large changes during the last two decades, including a severe reduction in cod and herring biomass but, at the same…”
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Two- and three-dimensional maturation reaction norms for the eastern Baltic cod, Gadus morhua by Vainikka, Anssi, Gårdmark, Anna, Bland, Barbara, Hjelm, Joakim

“…Vainikka, A., Gårdmark, A., Bland, B., and Hjelm, J. 2009. Two- and three-dimensional maturation reaction norms for the eastern Baltic cod, Gadus morhua. –…”
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Diet-dependent body morphology and ontogenetic reaction norms in Eurasian perch by Hjelm, Joakim, Svanbäck, Richard, Byström, Pär, Persson, Lennart, Wahlström, Eva

“…Individual morphology and performance are directly or indirectly under the influence of variation in resource levels. To study the effects of different…”
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Trends in cpue and related changes in spatial distribution of demersal fish species in the Kattegat and Skagerrak, eastern North Sea, between 1981 and 2003 by Casini, Michele, Cardinale, Massimiliano, Hjelm, Joakim, Vitale, Francesca

“…We explored the trends in ln-transformed catch per unit effort, defined as average weight (kg) per 1 h trawling, and the spatial distribution of 32 demersal…”
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Temporal variation in feeding morphology and size–structured population dynamics in fishes by Hjelm, Joakim, Johansson, Frank

“…Considerable variation in morphology associated with resource use is a classic example of local adaptation to the environment. We demonstrate that a temporal…”
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Comments on Local cod (Gadus morhua) revealed by egg surveys and population genetic analysis after longstanding depletion on the Swedish Skagerrak Coast by Svedäng et al by Cardinale, Massimiliano, Mariani, Stefano, Hjelm, Joakim

“…Abstract Svedäng et al. (2018) concluded that “the occurrence of locally spawned cod eggs suggests that spawning on the Swedish Skagerrak coast takes place,…”
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The “easy restriction” syndrome drive local fish stocks to extinction: The case of the management of Swedish coastal populations by Cardinale, Massimiliano, Svenson, Anders, Hjelm, Joakim

“…Spatially sensitive management built on detailed biological and socio-economic knowledge is required to establish sound fishing regulations and to avoid…”
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Regime shifts in exploited marine food webs: detecting mechanisms underlying alternative stable states using size-structured community dynamics theory by Gårdmark, Anna, Casini, Michele, Huss, Magnus, van Leeuwen, Anieke, Hjelm, Joakim, Persson, Lennart, de Roos, André M.

“…Many marine ecosystems have undergone ‘regime shifts’, i.e. abrupt reorganizations across trophic levels. Establishing whether these constitute shifts between…”
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A no-take zone and partially protected areas are not enough to save the Kattegat cod, but enhance biomass and abundance of the local fish assemblage by Sköld, Mattias, Börjesson, Patrik, Wennhage, Håkan, Hjelm, Joakim, Lövgren, Johan, Ringdahl, Katja

“…Abstract To supplement catch and effort regulations with the purpose to rebuild the cod (Gadus morhua) stock in Kattegat, Sweden and Denmark established a…”
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Food for Thought Eastern Baltic cod in distress: biological changes and challenges for stock assessment by Eero, Margit, Hjelm, Joakim, Behrens, Jane, Buchmann, Kurt, Cardinale, Massimiliano, Casini, Michele, Gasyukov, Pavel, Holmgren, Noel, Horbowy, Jan, Hussy, Karin, Kirkegaard, Eskild, Kornilovs, Georgs, Krumme, Uwe, Koster, Friedrich W., Oeberst, Rainer, Plikshs, Maris, Radtke, Krzysztof, Raid, Tiit, Schmidt, Joern, Tomczak, Maciej T., Vinther, Morten, Zimmermann, Christopher, Storr-Paulsen, Marie

“…The eastern Baltic (EB) cod (Gadus morhua) stock was depleted and overexploited for decades until the mid-2000s, when fishing mortality rapidly declined and…”
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The first large-scale assessment of three-spined stickleback (Gasterosteus aculeatus) biomass and spatial distribution in the Baltic Sea by Olsson, Jens, Jakubavičiūtė, Eglė, Kaljuste, Olavi, Larsson, Niklas, Bergström, Ulf, Casini, Michele, Cardinale, Massimiliano, Hjelm, Joakim, Byström, Pär

“…Abstract Declines in predatory fish in combination with the impact of climate change and eutrophication have caused planktivores, including three-spined…”
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Size matters: Short term loss and long term gain in a size-selective fishery by Cardinale, Massimiliano, Hjelm, Joakim

“…The maximum sustainable yield concept (MSY) and the ecosystem approach to fisheries management (EAFM) have been recently adopted by the European Commission…”
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Which factors can affect the productivity and dynamics of cod stocks in the Baltic Sea, Kattegat and Skagerrak? by Bryhn, Andreas C., Bergek, Sara, Bergström, Ulf, Casini, Michele, Dahlgren, Elin, Ek, Caroline, Hjelm, Joakim, Königson, Sara, Ljungberg, Peter, Lundström, Karl, Lunneryd, Sven Gunnar, Ovegård, Maria, Sköld, Mattias, Valentinsson, Daniel, Vitale, Francesca, Wennhage, Håkan

“…Stocks of Atlantic cod (Gadus morhua) in the Baltic Sea, Kattegat and Skagerrak (N. Europe) have been strongly exploited for decades bringing them into an…”
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Predators with Multiple Ontogenetic Niche Shifts Have Limited Potential for Population Growth and Top-Down Control of Their Prey by van Leeuwen, Anieke, Huss, Magnus, Gårdmark, Anna, Casini, Michele, Vitale, Francesca, Hjelm, Joakim, Persson, Lennart, de Roos, André M.

“…Catastrophic collapses of top predators have revealed trophic cascades and community structuring by top-down control. When populations fail to recover after a…”
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Unexpected fish and squid in the central Arctic deep scattering layer by Snoeijs-Leijonmalm, Pauline, Flores, Hauke, Sakinan, Serdar, Hildebrandt, Nicole, Svenson, Anders, Castellani, Giulia, Vane, Kim, Mark, Felix C, Heuzé, Céline, Tippenhauer, Sandra, Niehoff, Barbara, Hjelm, Joakim, Hentati Sundberg, Jonas, Schaafsma, Fokje L, Engelmann, Ronny

“…The retreating ice cover of the Central Arctic Ocean (CAO) fuels speculations on future fisheries. However, very little is known about the existence of…”
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Seal exclusion devices in cod pots prevent seal bycatch and affect their catchability of cod by Königson, Sara, Lövgren, Johan, Hjelm, Joakim, Ovegård, Mikael, Ljunghager, Fredrik, Lunneryd, Sven-Gunnar

“…In order to maintain a viable inshore fishing industry, it is important to limit the incidence of seal-inflicted damage to static fishing gear and additional…”
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