Density-dependent movement and front formation in Sea stars.
Johan van de Koppel – NIOZ Yerseke
Ecological theory contains an extensive amount of models on how organisms
interact. Only very few of these models are based or experiment that involve the
behaviour and movement of real organisms.
We test in mesocosm experiments how the interactions between organisms are
driven by their spatial movement and other behavioural elements. We use this
information to build mathematical models that include how organisms interact
in a spatially-explicit environment.
I have an opening for a student to work on:
Sea star and mussel interactions.
Mussel beds can experience explosive predation by sea stars, where local
outburst or concentration of sea stars can deplete a mussel beds in a matter of
weeks. Strikingly, this appears to be a localized phenomenon, where sea stars are
overwhelmingly present on one end of the mussel beds, forming a front of sea
stars, while hardly present at the other end.
We hypothesise that the movement behaviour of the sea stars is – in part –
responsible for the formation of these consumer fronts. Essential is that the sea
stars are very mobile when they are on bare sediment, but there movement
much reduces when they encounter stands of mussels. This question will/can be
addresses by laboratory experiments in the lab and with Individual-based
computer models.
We plan to:
1) Study the behaviour of the sea stars, to study whether it is density-dependent.
This can be done with new experiments, or can be based on existing moviematerial of sea stars in our experiments.
2) We will make models, if possible based on our experiments, in which we will
investigate how density-dependent movement by the sea stars affects the
formation of predator fronts, and can lead to quick depletion of mussel beds.
Doing an internship in Yerseke:
Location: The internship will be based at NIOZ Yerseke, (www.nioz.nl) in the
south of the Netherlands, which is a nice, cosy and well-equipped institute with
ample opportunities for combining fundamental and applied science, using
theoretical and empirical approaches.
If you are interested in this 4-5-6 month MSc project, contact:
Johan van de Koppel
Senior researcher, Department of Estuarine and Delta Systems (EDS), NIOZ
Honorary Professor, University of Groningen
Royal Netherlands Institute for Sea Research - Location Yerseke
P.O. Box 140, 4400AC Yerseke, The Netherlands
Email: [email protected]
Phone: 31 (0)113 577455
Homepage: johanvandekoppel.nl