Assessing population densities of ungulates
KEY POINTS- SLU assesses ungulate densities by commission from the Swedish EPA
- Data from different monitoring methods are combined
- The results are used in wildlife management
Project overview
Participants
More related research
Short summary
Sustainable ungulate management requires reliable estimates of population density and change, alongside forecasts of how harvest affects populations. SLU holds several commissions from the Swedish Environmental Protection Agency to assess ungulate densities and validate monitoring methods.
Since 2021, the Swedish University of Agricultural Sciences (SLU) has provided annual estimates of moose population density for Swedish moose management areas on behalf of the Swedish Environmental Protection Agency. Since the hunting year 2023/24, SLU has also been commissioned to provide an annual overview of the development and implementation of moose management. Since 2026, the commission has also included a forecasting tool for projecting future population size based on current population status and planned harvest.
The work provides recurring estimates of moose population size and change, reporting uncertainty and differences among areas. We also investigate how monitoring methods and models can be developed to cover additional ungulate species. Further work includes developing and combining models for moose, wild boar and red deer, and testing how data from, for example, camera traps and drones can complement existing monitoring.
We develop and validate population models using national management data and observations from ungulate reference areas. The evidence includes harvest records and monitoring data, including hunters' observations in the Moose Observation system, Älgobs. We examine how monitoring effort, geographical coverage and variation among years affect uncertainty in the estimates. Analyses of the age–sex composition of the harvest show how hunting is implemented and inform forecasts of population development.
The results help public authorities, landowners and hunters set harvest targets and evaluate management. Reliable decisions require extensive and geographically representative data collection; new methods need evaluation before they can replace established data sources.
The commissioned work is conducted in close and ongoing dialogue with the Swedish Environmental Protection Agency and the County Administrative Boards, with extensive training and communication of results at local and regional levels throughout Sweden.
Publications
Widemo, F. & K. Leonardsson. 2026. Moose harvest and population trend in Sweden 2025/26. 29 pp in Swedish. Department of wildlife, Fish & Environmental Studies Report, Swedish University of Agricultural Sciences. https://doi.org/10.54612/a.1pm5mk1h63
Hofmeester, T. R., Åstbom, D., Andersson, J., Frauendorf, M., Stenbacka, F., & F. Widemo. 2026. Monitoring moose using drones: Developing methods for assessing density, sex ratio and reproduction. Department of wildlife, Fish & Environmental Studies Report 2026.2. Swedish University of Agricultural Sciences. https://doi.org/10.54612/a.4mafh3bj8a
Lindström, T., Aguirre Perez, R., Barabás, G., Frauendorf, M., Widemo, F. & T. Hofmeester. 2026. Methods for assessing the wild boar population in Sweden. Naturvårdsverkets rapport 7227. https://www.naturvardsverket.se/4a4e46/globalassets/media/publikationer-pdf/7200/978-91-620-7227-8.pdf