My research deals with causes and consequences of migration and dispersal in freshwater organisms. A major focus is on seasonal migration in cyprinid fishes that leave their lake and move into streams and wetlands during winter. We believe that this is due to seasonal changes in habitat-specific trade-offs between costs and benefits, i.e. seasonal changes in growth and mortality risk in the lake and stream, respectively. We have also found that this is an example of partial migration where an individuals decision to migrate or not is in part determined by its condition. In future research we wish to study if there is a genetic component behind partial migration as well. We also predict that fish migration have far reaching consequences for the structure and dynamics of the lake ecosystem as a large proportion of the dominant zooplanktivorous fish leave the lake during a major part of the year.
A second project deals with the evolution of local adaptations and phenotypic plasticity of morphological and behavioural defences against predation. Theoretical models suggest that high migration or dispersal rates should favour plasticity over evolution of constitutive, locally adapted defences. We test this using freshwater prey organisms that show considerable variability in their dispersal ability. For example, our recent results suggest the importance of a high dispersal ability for the evolution of an inducible, morphological defence in a freshwater snail, Radix balthica.
Skov, C., Baktoft, H., Brodersen, J., Brönmark, C., Chapman, B. B. Hansson, L-A. and Nilsson, A. 2010. Sizing up your enemy: individual predation vulnerability predicts migratory probability. Proc. R. Soc. London
Brönmark, C. Brodersen, J., Chapman, B. Nicolle, A., Nilsson, P. A., Skov, C. and Hansson, L-A. 2010. Regime shifts in shallow lakes: the importance of seasonal fish migration. Hydrobiologia 646: 91-100
Brönmark, C, Skov, C, Brodersen, J, Nilsson, P A and Hansson, L-A 2008 Seasonal migration determined by a trade-off between predator avoidance and growth. PloS One 3(4): e1957
Dominici, P. Turesson, H., Brodersen, J.and Brönmark, C. 2008. Predator-induced morphology enhances escape locomotion in crucian carp. Proc. R. Soc. Lond. (B) 275: 195-201.
Turesson, H. and Brönmark, C. 2007. Predator-prey encounter rates in freshwater piscivores: effects of prey density and water transparency. Oecologia 153: 281-290
Åbjörnsson, K., Hansson, L-A. and Brönmark, C. 2004. Behavioral responses of prey from habitats with different predator regimes: local adaptation and heritability. Ecology 85: 1859-1866.
Carlsson, N., Brönmark, C. and Hansson, L.-A. 2004. Invading herbivory: The Golden apple snail alters ecosystem functioning in Asian wetlands. Ecology 85: 1575-1580
Rundle, S. and Brönmark, C. 2001. Inter- and intraspecific trait-compensation of defence mechanisms in freshwater snails. Proc Royal Soc Lond. 268: 1463-1468
Brönmark, C. and Hansson, L.A. 2000. Chemical communication in aquatic systems: an introduction. Oikos 88: 103-109
Brönmark, C. and Miner, J.G. 1992. Predator-induced phenotypical change in body morphology in crucian carp. Science 258: 1348-1350.
Brönmark, C. and Hansson, L-A. 2005. The Biology of Ponds and Lakes. 2nd ed. Oxford University Press.
Dr. Ben Chapman