The role of dimethyl sulfide (DMS) in pelagic tritrophic interactions


 nerc funded research project investigating The role of  dimethyl sulfide (DMS) in pelagic tritrophic interactions



The oceans contain only about 0.5% of total global biomass of primary producers. However, they provide a similar amount of total annual production to that on land and turnover times for organic matter is 1000-times faster in marine in comparison to terrestrial ecosystems. Therefore grazing by zooplankton is disproportionally important and competition among grazers is high.


Image by Glynn Gorick


All organisms release chemicals into the surrounding environment and at small spatial scales the high viscosity aqueous environment allows the persistence of chemical gradients and the reliable transmission of chemical cues. As a consequence chemosensory systems have evolved in a diverse range of marine taxa. in the vast 3D marine environment non-visual planktonic-grazers rely on infochemical (information conveying chemical) signals to locate prey or mates. Conversely, intense grazing pressure has lead to the evolution of defence mechanisms in phytoplankton.


Dimethylsulphoniopropionate (DMSP) is an abundant intracellular metabolite found in many phytoplankton. Algal DMSP can be converted into the climatically-relevant trace gas dimethyl sulfide (DMS), a process accelerated by natural senescence, viral lysis or grazing.


DMS and DMSP have been shown to act as infochemicals in a wide variety of species across a range of spatial and temporal scales from bacteria to seabirds. Microzooplankton and copepods are important grazers of phytoplankton primary productivity. The ability to detect and respond to DMS and DMSP, associated with rich prey patches, may provide vital foraging cues.


In this project we will assess the role of DMS and related compounds in mediating trophic interactions between small phytoplankton, microzooplankton and copepods. A series of laboratory and field experiments will determine grazing rates and DMS-production following microzooplankton grazing on different  phytoplankton species. The foraging responses of carnivorous copepods to the release of these infochemicals will be assessed.


The project includes a tied PhD Studentship aiming to mathematically model DMS-mediated trophic interactions. 



Algae & Grazers Gallery

 Research Team

Dr. Mark Breckels

Postdoctoral Researcher

Nicola Lewis

Nicola Lewis

Ph.D. Student




Steve Archer, Mark Breckels, Michael Steinke & Edd Codling









RESearch Information



Research Team


PI: Dr Michael Steinke



Dr Stephen D. Archer

Dr Edward A. Codling

Dr Susan Kimmance


PDRA: Dr Mark N. Breckels

Ph.D student: Nicola Lewis


RESEARCH Affiliations


Copyright (c) 2012 site maintained by Mark Breckels (mbreck -at- Plankton images courtesy of Glynn Gorick