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Per-Olav Moksnes

Researcher and lecturer in marine ecology, Department of Marine Ecology and Marine Environmental Coordinator at the Swedish Institute for the Marine Environment

My research interests are:


Professional history


Ongoing Research Activities

Larval dispersal and the design of marine reserve networks in Sweden (2009-)

Creation of marine reserves or marine protected areas (MPA) is an important instrument for mitigation of biodiversity loss and the management of natural resources. However, at present the effects of larval dispersal and population connectivity for optimal MPA design are largely neglected. The aim of the project is to assess how marine organism in Skagerrak and the Baltic Sea are connected through larval dispersal and identifying optimal designs of marine reserve networks in Sweden. The project is multidisciplinary including larval ecologists, biological modelers, oceanographers, spatial planners, managers of biodiversity and fish resources, and using a combination oceanographic and biological modeling producing dispersal probabilities. Critical data on vertical behavior for important species are collected through discrete plankton sampling at multiple depths along the Swedish coasts. The goal is to deliver tools to include dispersal and connectivity into spatial planning and management and to facilitate the development of an efficient and sustainable network of marine reserves in the Baltic Sea-Kattegatt-Skagerrak area.
Coordinator: Prof. Per Jonsson
Collaboration: Prof. Per Jonsson and Dr. Per Nilsson, Dept of Marine Ecology, Univ. of Gothenburg.
Prof. Kristofer Döös and Dr. Anders Engqvist, Department of Meteorology, Stockholm University
Prof. Joakim Hjelm and Dr. Mattias Sköld, Swedish Board of Fisheries.
Dr. Cecilia Lindblad, Swedish Environmental Protection Agency.
Funding: The Swedish Research Council FORMAS, Swedish Environmental Protection Agency, Swedish Board of Fisheries, Länsstyrelsen i Västra Götalands Län, Västra Götalandsregionen.

Larval behavior and dispersal in a microtidal system (2005-2009)

The majority of marine animals have aLarval crab on eelgrass. Photo by Per Moksnes planktonic larval stage that can disperse large distances. Our poor understanding of the processes affecting this dispersal pose a serious impediment to comprehending the ecology and evolution of marine species. The central hypothesis of this project is that larval behavior plays a critical role for the dispersal and recruitment success in marine animals, and that different tidal environments within the distribution of a species can result in different larval adaptations within a species. The general aim of the project is to investigate how larval behavior and oceanographic features interact to transport pelagic larvae in the Skagerrak-Kattegat system, and specifically to assess if species of the Swedish west coast have developed unique larval behaviors in adaptations to the microtidal conditions. Using dispersal of shore crab larvae Carcinus maenas as a model system, the questions is assessed with a multidisciplinary approach in collaboration with theoretical and empirical oceanographers, and molecular biologists, using a combination of larval behavioral studies in the laboratory, field studies using stratified plankton net sampling and continuous current measurements, and oceanographic modeling studies.
Coordinator: Per Moksnes
Dr. Bengt Liljebladh, Department of Earth Sciences, Gothenburg University.
Dr. Lennart Funkquist Swedish Meteorological and Hydrological Institute (SMHI)
Dr. Henrique Queiroga, University of Aveiro, Portugal
Master students: Olof Lang (2006), Ifan Arfandy (2009)
Funding: The Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS)

Restoration of eelgrass ecosystems in Sweden
(2010- )

Eelgrass beds play a key role in Swedish coastal ecosystems for marine biodiversity and natural resources by providing habitat and food for a number of organisms, including several commercial species. These ecosystems are presently impacted by eutrophication, and over 50% of the eelgrass has been lost from the Swedish NW coast. Because of slow horizontal growth and possibly due to local regime shifts, natural recovery of eelgrass may not occur even if growing conditions improve. The main goal of the proposed project is to assess if transplantation of live eelgrass could be used for restoration of eelgrass ecosystems in Sweden, both to restore eelgrass in areas where it has been lost, and to establish eelgrass in new areas to compensate for habitat lost to coastal exploitation. Using a multidisciplinary team of scientist and managers, and a combination of model and empirical studies, we aim to (1) identify environmental threshold conditions for eelgrass survival, and potential feed-back mechanism that prevent the return of eelgrass, and (2) evaluate a number transplantation methods successfully used in other parts of the world to find the best methods for Swedish conditions. Based on these results, and in dialog with coastal managers, we will develop a detailed management guideline regarding methods for site-selection, transplantation and evaluation of results for eelgrass restoration in Sweden.
Coordinator: Per Moksnes
Collaboration: Dr. Ingela Isaksson, Länsstyrelsen i Västra Götalands Län, Dr. Fredrik Larsson, National Board of Fisheries, and Mats Lindegarth, Dept of Marine Ecology, University of Gotheburg.
Funding: Swedish Environmental Protection Agency (Naturvårdsverket), Länsstyrelsen i Västra Götalands län.

Bottom-up and top-down control in eelgrass and Fucus communities (2003- )

Cage experiment in eelgrass bedEutrophication was long considered to be the only explanation for vegetation changes in shallow coastal communities in Sweden where ephemeral algae have displaced eelgrass and Fucus-algae in many areas. In the last years we have tested and found support for the hypothesis that overfishing and the loss of large fish predators from the coastal systems has contributed to the loss of perennial vegetation by causing a trophic cascade that has decreased the biomass of algal mesograzers and released the ephemeral algae from grazing control. We are using a combination of empirical field experiments and theoretical models to assess how nutrient pollution, grazing and predation interact and affect the abundance of fouling organisms, the production of eelgrass and Fucus, and the diversity of organisms in the communities along the Swedish west coast and in the Baltic Sea. The studies are part of a wide collaboration between several different scientists at the department of marine Ecology as well as with scientist from Stockholm University, the Linnaeus University, the Åbo Academy University in Finland and the University of Southern Denmark in Denmark.
Collaboration: Prof. Susanne Baden, Prof. Per Åberg and Dr. Carl-Johan Svensson Dept of Marine Ecology, University of Gothenburg. Prof. Lena Kautsky and Sonja Råberg, Stockholm University, Stefan Tobiasson, the Linnaeus University, Dr. Christoffer Boström, Åbo Akademi University, Finland and Prof. Marianne Holmer, University of Southern Denmark, Denmark
PhD-student: Martin Gullström (2006)
Master-students: Malin Persson, Sandra Andersson (2005), Therese Jephson (2006)
Funding: Swedish Environmental Protection Agency (Naturvårdsverket) and the research program Marine Biodiversity Patterns and Processes (MARBIPP)

Small-scale aquacultures of mud crabs as a sustainable livelihood in East Africa (2009- )

Per Moksnes in mangroveA rapid increase of coastal populations in East Africa and impoverishments of coastal resources increase the need for livelihood options. The goal of the project is to develop small-scale, grow-out aquaculture of mud crabs as an alternative source of income for resource-poor coastal communities in East Africa. Specific aims are to increase the understanding of the juvenile ecology of mud crabs, and to develop new methods for obtaining mud crab seeds without negative impact on wild populations, to secure sustainable local resources for crab feed, and to develop new methodologies to grow mud juvenile crabs to commercial size that is environmentally, economically and culturally sustainable. The project use an interdisciplinary approach to (1) increase our understanding of key ecological processes of early life-stages of mud crabs, (2) develop low technology, extensive methods to farm mud crabs with minimum impact on local resources and the environment, and (3) evaluate the potential for mud crab aquaculture in a socio-economic context. The studies are carried out in both Tanzania and Kenya.
Coordinator: Per Moksnes
Collaboration: Dr. Max Troell, The Beijer Institute, Stockholm University
Prof. Narriman Jiddawi, Inst. of Marine Sciences, Zanzibar, Univ. of Dar Es Salaam, Tanzania.
Dr. Razack Lokina, Department of Economics, University of Dar Es Salaam, Tanzania.
Dr. Jacob Ochiewo and David Mirera, Kenya Marine and Fisheries Research Institute, Kenya.
Humphrey Mahudi, Mafia Island Marine Park, Tanzania.
PhD-student: David Mirera (2009- )
Master-students: Louise Karlsson, Kajsa Palmqvist (2009), Emma Björkvik (2010)
Funding: Western Indian Ocean Marine Science Association (WIOMSA; MASMA-grant), SIDA (Minor Field Study grants).

Climate Change and Predatory Invasion of the Antarctic Marine Environment (2010- )

Global climate change is altering polar marine ecosystems through rising temperatures. As the Southern Ocean warms, the physiological barriers to invasion by predatory crabs are disappearing, which could have catastrophic implications for the endemic shelf fauna of Antarctica. The goal of the study, a collaborative research effort between scientists from Sweden, the USA and the United Kingdom, is to assess the status of predatory invasions and its effect on the benthic shelf fauna of Antarctica. Specific aims are to assess the distributions of larvae, juveniles, and adults of invasive predators on the slope and shelf of western Antarctica, to identify mesoscale oceanographic features that can facilitate the invasion of predatory larvae, and to document possible changes in the endemic benthic shelf fauna following the invasion of predators. The methods will involve plankton sampling at multiple depth, sampling demersal crab larvae and juveniles with benthic sledges, and sampling the macrobenthic assemblages photographically using the an Autonomous Underwater Vehicle (AUV). The study will be carried out on the Oden and NB Palmer Southern Ocean Cruise 2010-2011.
Coordinator: Per Moksnes
Collaboration: Prof. Richard Aronson, Florida Institute of Technology, USA,
Prof. James McClintock, Dept of Polar Marine Biology, Bruce Univ of Alabama at Birmingham.
Prof. Sven Thatje, National Oceanography Centre, University of Southampton, UK
Prof. Jon Havenhand and Kajsa Tönnesson Dept of Marine Ecology, Univ. of Gothenburg
Funding: The Swedish Research Council VR, Swedish Polar Research Secretariat,
US National Science Foundation Office of Polar Programs (NSF/OPP).

Professional history

2009- Permanent researcher and lecturer, Department of Marine Ecology,
Environmental Coordinator at the Swedish Institute for the Marine
Environment, University of Gothenburg
2004-2009 Assistant professor, Dep. of Marine Ecology, University of Gothenburg
2005 Docent in Marine Ecology, University of Gothenburg
2005-2006 Coordinating lecturer in marine biology, Lunds University
2003-2004 Researcher Dep. of Marine Ecology, University of Gothenburg
2001-2002 Post Doc. with Prof. Ken Heck, Dauphin Island Sea Lab, AL, USA
1999-2000 Lecturer and researcher, University of Gothenburg
1999 Ph.D. Marine Zoology, Dep. of Marine Ecology, University of Gothenburg,
1994 M.Sc. Marine Biology, University of Gothenburg

Peer-review publications

1. Moksnes P-O, Lindahl U, and C. Haux. 1995.  Metallothionein as a bioindicator of heavy metal exposure in the tropical shrimp, Penaeus vannamei: A study of dose-dependent induction. Marine Environmental Research. 39:143-146

2. Pihl L, Isaksson I, Wennhage H, and P-O. Moksnes. 1995.  Recent increase of filamentous algae in shallow Swedish bays: Effects on the community structure of epibenthic fauna and fish.  Netherland Journal of Aquatic Ecology. 29:349-358

3. Moksnes P-O, Lipcius R, Pihl L. and J. van Montfrans. 1997.  Cannibal-prey dynamics in young juveniles and postlarvae of the blue crab. Journal of Experimental Marine Biology Ecology. 215:157-187

4. Moksnes P-O, Pihl L. and J. van Montfrans. 1998.  Predation on postlarvae and juveniles of the shore crab Carcinus maenas: Importance of shelter, size and cannibalism.  Marine Ecology Progress Series. 166:211-225

5. Hedvall O, Moksnes P-O, and L. Pihl 1998.  Active habitat selection of postlarvae and juvenile shore crabs Carcinus maenas: A laboratory study in an annular flume. Hydrobiologia. 373/375: 89-100

6. Pihl L, Svensson A, Moksnes P-O, and H. Wennhage. 1999.  Distribution and production of ephemeral algae in shallow coastal areas on the Swedish west coast. Journal of Sea Research. 41:281-294

7. Moksnes P-O, and H. Wennhage. 2001.  Methods for estimating decapod larval supply and settlement: Importance of larval behavior and development stage. Marine Ecology Progress Series. 209:257-273.

8. Moksnes P-O. 2002. The relative importance of habitat specific settlement, predation and juvenile movements for distribution and abundance of young juvenile shore crabs Carcinus maenas. Journal of Experimental Marine Biology Ecology. 271:41-73.

9. Queiroga H, Moksnes P-O, and S. Meireles. 2002. Vertical migration behavior in the larvae of the common shore crab Carcinus maenas (L.), from a micro-tidal fjord in Sweden. Marine Ecology Progress Series. 237:195-207.

10. Moksnes P-O, Hedvall O, and T. Reinvald. 2003.  Swimming and settlement behavior in shore crab megalopae: Why do postlarvae emigrate from nursery habitats? Marine Ecology Progress Series. 250:215-230.

11. Moksnes P-O. 2004 Self-regulating mechanisms in cannibalistic populations of juvenile shore crabs Carcinus maenas. Ecology. 85:1343-1354.

12. Moksnes P-O. 2004. Interference competition for space in nursery habitats: density-dependent effects on growth and dispersal in juvenile shore crabs Carcinus maenas. Marine Ecology Progress Series. 281:181-191.

13. Moksnes P-O, and KL Heck Jr. 2006. The relative importance of habitat selection and predation for the distribution of blue crab megalopae and young juveniles. Marine Ecology Progress Series 308:165-181.

14. Jephsson T, P Nyström, P-O Moksnes and S Baden. 2008. Trophic interactions within Zostera marina beds along the Swedish coast. Marine Ecology Progress Series 369: 63-76.

15. Persson M., S. Andersson, S. Baden and P-O Moksnes. 2008. Trophic role of the omnivorous grass shrimp Palaemon elegans (Rathke) in a Swedish eelgrass system. Marine Ecology Progress Series 371: 203–212.

16. Moksnes P-O, Gullström M, Tryman K. and S. Baden. 2008. Trophic cascades in a temperate seagrass community. Oikos 117: 763-777.

17. Andersson S., M. Persson, P-O Moksnes and S. Baden. 2009. The role of the amphipod Gammarus locusta as a grazer on macroalgae in Swedish seagrass meadows. Marine Biology. 156:969-981.

18. Holmer, M, Baden S., Moksnes P-O., Boström, C. 2009. Regional variation in stable sulfur isotopic composition of eelgrass (Zostera marina) along a salinity gradient from the Baltic Sea to Skagerrak. Aquatic Botany. 91:303-310.

19. Baden S., Boström, C., Tobiasson S, Arponen, H and Moksnes P-O. (in press). Relative importance of trophic interactions and nutrient enrichment in seagrass ecosystems: A broad-scale experimental assessment. Limnology and Oceanography.

(publications cited 425 times in April 2010; ISI Web of Knowledge)

Popular science publications and reports

1. Moksnes, P-O. and L. Pihl. 1995.  Distribution and production of ephemeral algae in shallow coastal areas in Göteborg och Bohus län. State Department of Göteborg and Bohus län, Environmental Division. 10:1- 22.

2. Pihl, L., Svensson A., Moksnes, P-O. and H. Wennhage. 1999.  Distribution and production of ephemeral algae in shallow coastal areas in Göteborg och Bohus län 1994-1996.  State Department of Göteborg and Bohus län, Environmental  Division. 22:1-18.

3. Moksnes, P-O. 1999.  Fintrådiga alger hjälper strandkrabban genom flaskhalsen. HavsUtsikt-om havsforskning och marin utvecklingsverksamhet i Sverige. 2/99.

4. Baden S. and P-O. Moksnes 2005.  Gödning och överfiske förstör fiskens barnkammare. Miljöforskning för ett uthålligt samhälle (FORMAS tidning). 4/05.

5. Eklöf J, Gullström M, Moksnes P-O, Baden S 2009. Sjögräsängar - hotade av både övergödning och överfiske? HavsUtsikt No. 1.

6. 1. Moksnes P-O. 2009. Restaurering av ålgräsängar i Sverige. Länsstyrelsen Västra Götalands län. Rapport 2009:26

7. Moksnes P-O Går det att restaurera ålgräsängar? Västerhavet 2010.

8. Moksnes P-O, S Råberg, S Baden, and L Kautsky. (in press) Rovfiskars betydelse för vegetationen längs Sveriges kuster. Havet Rapporten 2010.

Contact information

Per-Olav Moksnes

University of Gothenburg
Department of Biological and Environmental Sciences
Box 461

Visiting address
Carl Skottbergs gata 22B


+46 (0)31-786 27 10


+46 (0)31-786 27 27



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