To better understand the lives of animals – for example, their social systems, migratory behaviour, or interactions with the environment – researchers need detailed data on how animals behave in their natural habitats. But how can this data be collected in the field, i.e. far away from the technical resources of a fully equipped behavioural laboratory? For this purpose, researchers from the Cluster of Excellence “Collective Behaviour” at the University of Konstanz (Germany) have developed the mobile camera system “3D-SOCS” (short for “3D Synchronized Outdoor Camera System”) and used it for studying wild passerine birds.
The state-of-the-art behavioural data collection system has now been published in the journal Methods in Ecology and Evolution. It enables precise, automated, markerless 3D tracking of the postures and movements of multiple birds simultaneously using two or more synchronized cameras. “3D-SOCS is one of the first systems to demonstrate complete 3D posture tracking of multiple individuals in the wild, as current 3D tracking is almost exclusively done indoors and with captive animals”, says Alex Hoi Hang Chan, who led the study along with Michael Chimento.
“3D-SOCS is a leap forward for the study of animal behaviour in wild, free-living animals”, says Chimento. “Our method opens new doors for studying cognition and social behaviour under ecologically valid conditions.”
A closer look at wild birds’ attention use
To showcase 3D-SOCS’ potential, the team deployed it in the woods near the Max Planck Institute of Animal Behavior in Möggingen (Germany), inhabited by populations of great tits and blue tits. In a field experiment, the researchers presented the local birds with visual stimuli – from mealworms to a taxidermy bird – and used 3D-SOCS to determine how the birds oriented their heads in response to these objects. With the data from the mobile camara system, they were able to infer each bird’s visual field use and even lateralization (the preference for using one eye over the other), thereby uncovering subtle differences in the visual attention of individual birds.
Beyond measuring behaviour, 3D-SOCS offers powerful tools for ecological monitoring. Using posture data provided by the system, the researchers estimated the birds’ body volume as a proxy for weight and achieved very high correlation with the values they measured using a scale. The advantage of estimating such body parameters using the camera system is obvious: It is a non-invasive alternative to capture-and-weigh approaches.
The method thus paves the way for an automated tracking of wild animals’ body or health conditions and even species classification in the field. What is more: 3D-SOCS is an open platform. In the spirit of open science, all hardware plans and software pipelines are freely available, thus enabling easy adaptation to different study systems and species.
A step forward for behavioural research in the field
Overall, 3D-SOCS opens up a new avenue for synergies between laboratory and field research. By enabling fine-scale behavioural tracking in the wild with a level of detail previously restricted to lab environments, 3D-SOCS bridges the gap between controlled, high-resolution lab studies and ecologically valid but often less detailed field observations. “This allows for an integrated approach where the strengths of both worlds can be combined, potentially establishing a new interdisciplinary field in behavioural and cognitive ecology”, says Fumihiro Kano, the senior author of the study.
As the demand for high-resolution behavioural data grows in ecology and conservation science, 3D-SOCS offers an accessible solution. “This new window into the secret lives of animals is poised to transform the way we study behaviour – from the forest floor to the treetops”, says Kano.
Key facts:
- Original publication: Michael Chimento, Alex Hoi Hang Chan, Lucy M. Aplin, Fumihiro Kano. 2025. Peering into the world of wild passerines with 3D-SOCS: synchronized video capture and posture estimation. Methods in Ecology Evolution; DOI: 10.1111/2041-210x.70051
- Researchers from Konstanz (Germany) developed a unique camara system (3D-SOCS) that allows precise, automated, markerless 3D tracking of the postures and movements of wild birds.
- Alex Hoi Hang Chan and Dr Michael Chimento are part of the working group of Dr Fumihiro Kano, Junior research group leader in the Centre for the Advanced Study of Collective Behaviour (University of Konstanz).
- The Centre for the Advanced Study of Collective Behaviour at the University of Konstanz is a global hotspot for the study of collective behaviour across a wide range of species and across scales of organization. It is a Cluster of Excellence within the framework of the German Excellence Strategy of the federal and state governments.
- Open Science: All hardware plans and software pipelines for 3D-SOCS are freely available, thus enabling easy adaptation to different study systems and species
- Funding: German Research Foundation (DFG) and Swiss State Secretariat for Education, Research and Innovation (SERI)
Note to editors:
Photos are available here:
Link: https://www.uni-konstanz.de/fileadmin/pi/fileserver/2025_extra/neues_fenster_1.png
Caption: A great tit gazes at a stimulus with its left eye. The yellow lines show the head position estimated by 3D-SOCS. The other lines point towards the center of the estimated lateral and binocular visual fields.
Copyright: University of Konstanz, Comparative Cognition and Sociality Lab
Link: https://www.uni-konstanz.de/fileadmin/pi/fileserver/2025_extra/neues_fenster_2.png
Caption: 3D-SOCS is a mobile laboratory for 3D-tracking. In the example, six cameras inside the cage track the movements and postures of any great tits or blue tits that enter it. The system is battery-powered and can be used in the field.
Copyright: University of Konstanz, Comparative Cognition and Sociality Lab
Journal
Methods in Ecology and Evolution