About the JollesLab

A highly coordinated school of three-spined sticklebacks swimming in the clear blue waters of the Bodensee. Photo: JW Jolles.

Overview

The JollesLab is a research group led by Dr Jolle Jolles at the Max Planck Institute of Ornithology, Konstanz, Germany. Our research is focused on unravelling the role of individual heterogeneity in animal social systems across ecological scales. Using an interdisciplinary approach, we bring the strong mechanistic approach of Collective Behaviour Research into a Behavioural Ecology framework. By a combination of controlled laboratory experiments, field observations, and computer simulations we investigate the fundamental properties of consistent phenotypic variation, its consequences for collective behaviour and in turn its effect on individual fitness, and its resilience against strong ecological selection pressures. We mainly work with fish, in particular the three-spined stickleback, due to their large  phenotypic variation and great tractability.

Fish Lab

Besides making use of the sophisticated fish labs in the Department of Collective Behaviour, I have recently completed building my own experimental lab at the Limnological Institute at the University of Konstanz. Key feature of my new lab is the large experimental setup that enables the automatic testing of up to 8 fish simultaneously as well that of large schools of fish to look at both group-level and among-group level processes. The setup consists of a 1.5 m x 2.5 m tank that can be divided into 8 smaller tanks. The top part of the setup contains both visible and IR lighting, thus enabling us to test fish under a large range of light levels, including complete darkness. A total of eight Raspberry Pi computers with carefully calibrated cameras enable the automated recording of the fish. We have large social housing tanks in the basement of the institute and have custom-build individual housing tanks that enable the holding of up to 128 individual fish.

A look inside the controlled recording setup of our lab with a calibrated Raspberry Pi camera in the foreground.

Automated recording and tracking

Our research uses a strong mechanistic approach and often requires the testing of large number of individuals to look at the effects of individual heterogeneity in animal groups. Therefore I have developed my own software (AnimRec) to easily record experimental trials in a controlled way and software to automatically track both individuals and groups of animals (AnimTrack). Recently I have released AnimRec as a public Python package such that also other researchers will be able to set-up and work with a cheap yet reliable controlled recording system. It consists of a main recorder module and a number of helper methods that facilitate setting-up the the Raspberry Pi, configuring the the camera, scheduling recordings, and converting recorded media.

AnimTrack is a Python package I have written that enables the automatic tracking of both individual animals as well as groups of tagged and untagged animals in a range of environments. It provides highly detailed spatio-temporal output of individual and group movement dynamics as well as behavioural state changes. It contains a number of helper methods, including camera calibration, dynamic tracking parameter configuration, interactive error checking, custom video output, and a manual tracker function. Both AnimRec and AnimTrack make use of a large number of utility image, mathematical and general functions from the associated AnimLab package, publicly available here.

Screenshot of AnimTrack tracking a video of a school of five three-spined sticklebacks with known identities. Lines indicate association network.

Field work

All fish we study in the lab are from the wild, caught with a number of different fishing techniques. Increasingly we are also starting to conduct field work to study the natural distribution of fish schools and their composition as well as predator-prey dynamics. Recently I have also started to explore possibilities of setting up my own field site to investigate how different phenotypes deal with invasion dynamics and the effects of climate change and what social consequences this may have. For this I have found great potential in the Spanish Pyrenees, with many parallel streams that show severe effects of drought, flash floods, human disturbance, and invasive species. Hopefully more about this type of work in the coming year!