I am an aquatic ecologist and did my PhD (University of Potsdam/Germany) by studying the nutrition of Daphnia (Cladocera, freshwater zooplankton species) and its physiological responses to changing environmental conditions. I also started developing my theory on resource co-limitation (i.e. the simultaneous limitation of organisms by multiple resources) using simple mathematical models, which were tested experimentally using Daphnia as model system. During my postdocs in Bergen/Norway, Sydney/Australia, and Stechlin/Germany I have studied potential effects of ocean acidification on marine macro-zooplankton (krill and mysids), theoretical aspects of resource co-limitation (development of a generally applicable framework), and changes in zooplankton community composition in response to multiple stressors (increasing humic substance concentration and nutrient load), respectively. From June 2016 onwards I joined CEES as a researcher involved in the EVODEF project (The evolution of defence systems: theory and experiment, led by Øistein Holen), where I will study inducible defence traits of Daphnia in the laboratory, thereby testing predictions of theoretical models.
I have a broad interest in general ecological concepts and theories with the focus on aquatic food webs and the interactions of their organisms. I am particularly interested in the interactions between phytoplankton, zooplankton and their predators as well as the effects of changing food quality on fitness and body composition of zooplankton. I am also interested in the limitation of consumers by multiple resources as well as the effects of changing environmental conditions (e.g. temperature or predation threat) on aquatic organisms. My research is guided by a special interest in identifying underlying mechanisms that drive an organism’s physiology and adaptation potential or observed changes in species interactions. I like to use multi-factorial experiments in combination with well-founded ecological theory as one of my aims is to generate data that can be integrated into mathematical models, which are indispensable to analyse and understand multi-factorial dependencies in nature.
- Halvorson, Halvor M.; Sperfeld, Erik & Evans-White, Michelle, A. (2017). Quantity and quality limit detritivore growth: mechanisms revealed by ecological stoichiometry and co-limitation theory. Ecology. ISSN 0012-9658. 98(12), s 2995- 3002 . doi: 10.1002/ecy.2026 Full text in Research Archive.
- Santonja, Mathieu; Minguez, Laetitia; Gessner, Mark O. & Sperfeld, Erik (2017). Predator–prey interactions in a changing world: humic stress disrupts predator threat evasion in copepods. Oecologia. ISSN 0029-8549. 183(3), s 887- 898 . doi: 10.1007/s00442-016-3801-4
- Sperfeld, Erik; Mangor-Jensen, Anders & Dalpadado, Padmini (2017). Effects of increasing pCO2 on life history traits and feeding of the littoral mysid Praunus fexuosus. Marine Biology. ISSN 0025-3162. 164(173), s 1- 12 . doi: 10.1007/s00227-017-3203-0 Full text in Research Archive.
- Dalpadado, Padmini; Hop, Haakon; Rønning, Jon S.; Pavlov, Vladimir; Sperfeld, Erik; Buchholz, Friedrich; Rey, Alina & Wold, Anette (2016). Distribution and abundance of euphausiids and pelagic amphipods in Kongsfjorden, Isfjorden and Rijpfjorden (Svalbard) and changes in their relative importance as key prey in a warming marine ecosystem. Polar Biology. ISSN 0722-4060. 39(10), s 1765- 1784 . doi: 10.1007/s00300-015-1874-x
- Kalinkat, Gregor; Cabral, Juliano S.; Darwall, William; Ficetola, G. Francesco; Fisher, Judith L.; Giling, Darren P.; Gosselin, Marie-Pierre; Grossart, Hane-Peter; Jähnig, Sonja C.; Jeschke, Jonathan M.; Knopf, Klaus; Larsen, Stefano; Onandia, Gabriela; Pätzig, Marlene; Saul, Wolf-Christian; Singer, Gabriel; Sperfeld, Erik & Jaric, Ivan (2016). Flagship umbrella species needed for the conservation of overlooked aquatic biodiversity. Conservation Biology. ISSN 0888-8892. 31(2), s 481- 485 . doi: 10.1111/cobi.12813
- Dalpadado, Padmini; Arrigo, Kevin R.; Hjøllo, Solfrid Sætre; Rey, Francisco; Ingvaldsen, Randi; Sperfeld, Erik; van Dijken, Gert L.; Stige, Leif Christian; Olsen, Are & Ottersen, Geir (2014). Productivity in the Barents Sea - Response to recent climate variability. PLoS ONE. ISSN 1932-6203. 9(5) . doi: 10.1371/journal.pone.0095273 Full text in Research Archive.
- Sperfeld, Erik; Mangor-Jensen, Anders & Dalpadado, Padmini (2014). Effect of increasing sea water pCO2 on the northern Atlantic krill species Nyctiphanes couchii. Marine Biology. ISSN 0025-3162. . doi: 10.1007/s00227-014-2511-x
- Sperfeld, Erik (2016). Studying nutritional ecology and the evolution of inducible defences using Daphnia as model organism.