Sveučilište u Zagrebu 
HMSC workshop
Analysing camera trap data for Joint Species Distribution Analysis
Faculty of Veterinary Medicine University of Zagreb, Croatia 6 – 7.10.2026
Camera traps record which species are present across many sites simultaneously, making them ideal for community-level analysis. Hierarchical Modelling of Species Communities (HMSC) uses this multi-species occurrence data and asks questions that single-species models cannot: which species share the same habitat preferences, which pairs avoid or attract each other beyond what habitat alone explains, and how community composition shifts across the landscape. It does this while accounting for the fact that detection is imperfect and varies between stations — a reality of any camera trap dataset. Rather than analysing one species at a time, HMSC borrows information across all species at once, which is particularly useful when detections of any individual species are sparse.
Camera trap data is particularly well suited for analysing relationships between species and their habitats, but to make the most of the data, having appropriate statistical tools available can make all the difference. In this workshop participants will be introduced to the usage of HMSC for studying the co-distribution and temporal variation of species while integrating habitat use from photographic evidence.
The workshop will cover the considerations required for using camera trap data for HMSC and practical data analysis. The workshop will make use of example data gathered during the LIFE Lynx and COMPASS projects in the Dinaric Mountains, but participants are also welcomed to bring their own annotated data for feedback and advice.
The workshop will be led by John Loehr (https://researchportal.helsinki.fi/en/persons/john-loehr/) and Caio Graco Rodrigues Leandro Roza (https://researchportal.helsinki.fi/en/persons/caio-graco-rodrigues-leandro-roza/) from the University of Helsinki, Finland.
The workshop will be held at the Faculty of Veterinary Medicine University of Zagreb (Heinzelova 55, 10000 Zagreb, Croatia). It is organized as part of the implementation of the COMPASS project (Conservation Medicine – Apex Predators as Sentinels of Ecosystem Health IP-2025-02-1750), financed by Croatian Science Foundation. Participation is free, but participants must cover their own travel, accommodation and meal costs (coffee breaks will be provided by the organizers).
Registration link https://forms.gle/gDs7EzTVwDxf3Diq5 (application deadline June 15).
Questions related to workshop content can be sent to John Loehr (john.loehr@helsinki.fi), for all other questions please contact Magda Sindicic (msindicic@vef.unizg.hr).
Workshop schedule
Day 1.
10:00-11:00: What is HMSC? (General introduction)
11:00-12:00: HMSC and joint species distribution research
12:00-13:00: Camera trapping strategy and protocol for HMSC
13:00 – 14:30 Lunch break
14:30- 16:30: Using R for statistical analysis
Day 2.
9:00-10:00 Introduction to HMSC in R
10:00-13:00 Working examples with R
13:00 – 14:30 Lunch break
14:30-16:30 Participants’ case studies and discussion of research ideas and questions
Prerequisites
The workshop is designed so that participants with only basic knowledge of R and statistical analysis can participate, however, more advanced users will also benefit. Please bring your own computers.
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