Research on Arctic herbivory has a long tradition, but recent literature syntheses have highlighted important knowledge gaps. Given the rapid pace of climate change in the Arctic and the limited resources available, prioritizing research and management efforts is an urgent task. To identify emerging scientific and management priorities in Arctic herbivory research for the next decade, and as a contribution to the fourth International Conference on Arctic Research Planning (ICARP IV) we conducted a horizon scan within the Arctic herbivory research community.
We collected nearly 300 suggestions from 85 experts through online surveys and an in-person workshop. After analyzing their responses, we identified eight key scientific priorities and eight key management priorities centred on (a) understanding and integrating fundamental ecological processes across multiple scales from individual herbivore–plant interactions up to regional and decadal scale vegetation and animal population effects; (b) evaluating climate change feedbacks; and (c) developing new research methods. Our analysis provides a strategic framework for broad, inclusive, interdisciplinary collaborations to optimise terrestrial herbivory research and sustainable management practices in a rapidly changing Arctic.
The resulting paper is available as an open access publication in Arctic Science: BARRIO, I.C., VUORINEN, K.E.M.V., BARBERO-PALACIOS, L., DEFOURNEAUX, M., PETIT BON, M., GREER, E.A., ANDERSON, H., HORSTKOTTE, T., LECOMTE, N., WINDIRSCH, T., FERRARO, K., FORBES, B.C., FORBEY, J.S., GARCÍA CRIADO, M., HAGENBERG, L., HIK, D., KATER, I., MACEK, P., MOEN, J., SUNDQVIST, M.K., SZEJGIS, J., VILLOSLADA, M., ZAJA, E., BERTHELOT, F., BJÖRNSDÓTTIR, K., CUNOW, J., DEN HERDER, M., ESKELINEN, A., HAYES, K., HOLLISTER, R.D., Í HARALDSSTOVU, K., JÓNSDÓTTIR, I.S., KRISTENSEN , J.A., LAMERIS, T., OKSANEN, L., OKSANEN, T., OLOFSSON, J., PARK, T., PEDERSEN, Å.Ø., RAMIREZ, J.I., RAVOLAINEN, V.T., ROY, A., RYDE, I., SCHMIDT, N.M., SCHROFNER-BRUNNER, B., SKARIN, A., SPEED, J., TE BEEST, M., TILLMAN, M., TINOCO TORRES, R., TRAYLOR, W., VIRTANEN, R., WHEELER, H.C., ALATALO, J.M., AXMACHER, J.C., BARTOLOMÉ FILELLA, J., COOPER, E., GEANGE, S., GILG, O., GROGAN, P., HERNÁNDEZ-CASTELLANO, C., HØYE, T., KERBY, J.T., KLANDERUD, K., KOLTZ, A.M., LANG, J., LE MOULLEC, M., LOONEN, M.J.J.E., MACIAS-FAURIA, M., POST, E., SERRANO, E., SIEWERT, M., SOKOLOV, A., SOKOLOVA, N., SUOMINEN, O., TAMAYO, M., TEREKHINA, A., VOLKOVITSKIY, A., KAMENOVA, S. (2025) Emerging priorities in terrestrial herbivory research in the Arctic. Arctic Science 11: 1-26 link to publisher
The horizon scan exercise was a long process that included brainstorming at the HN meeting organized in Cambridge Bay in June 2023, two online surveys and one in-person workshop organized in parallel to the Nordic Society Oikos conference in Lund, in March 2024.
Funding to support the participation of early career scientists to the HN meeting in Cambridge Bay and the workshop in Lund was made available through the Terrestrial Working Group of the International Arctic Science Committee.
As part of the TUNDRAsalad project and as a follow up on the HN work on the systematic map of herbivore studies in the Arctic, we conducted a systematic review to synthesize the effects of herbivore diversity on tundra ecosystem functioning. We first published a protocol for conducting the systematic review that we then used to actually do the review.
The project was coordinated by Laura Barbero Palacios.
Publications related to the systematic review
BARBERO-PALACIOS, L., BARRIO, I.C., GARCÍA CRIADO, M., KATER, I., PETIT BON, M., KOLARI, T.H.M., BJØRKÅS, R., TREPEL, J., LUNDGREN, E., BJÖRNSDÓTTIR, K., HWANG, B.C., BARTRA-CABRÉ, L., DEFOURNEAUX, M., RAMSAY, J., LAMERIS, T.K., LEFFLER, A.J., LOCK, J.G., KUOPPAMAA, M.S., KRISTENSEN, J.A., BJORKMAN, A.D., MYERS-SMITH, I., LECOMTE, N., AXMACHER, J.C., GILG, O., DEN HERDER, M., PAGNEUX, E.P., SKARIN, A., SOKOLOVA, N., WINDIRSCH, T., WHEELER, H.C., SERRANO, E., VIRTANEN, T., HIK, D.S., KAARLEJÄRVI, E., SPEED, J.D.M., SOININEN, E. (2024) Herbivore diversity effects on Arctic tundra ecosystems – a systematic review. Environmental Evidence 13(1):6 https://doi.org/10.1186/s13750-024-00330-9
BARRIO, I.C., BARBERO-PALACIOS, L., KAARLEJÄRVI, E., SPEED, J.D.M., HEIÐMARSSON, S., HIK, D.S., SOININEN, E.M. (2022) What are the effects of herbivore diversity on tundra ecosystems? A systematic review protocol. Environmental Evidence 11:1 https://doi.org/10.1186/s13750-022-00257-z
The project “Herbivores in the tundra: linking diversity and function (TUNDRAsalad)” was a three-year project (2021-2023) funded by the Icelandic Research Fund, that investigated the role of herbivore diversity in tundra ecosystems. The project was led by Isabel C Barrio at the Agricultural University of Iceland.
Partners included Elina Kaarlejärvi (University of Helsinki), Eeva Soininen (UiT The Arctic University of Norway), James Speed (Norwegian University of Science and Technology), David Hik (Simon Fraser University), Mathilde Defourneaux (Agricultural University of Iceland), Laura Barbero Palacios (Agricultural University of Iceland), Noémie Boulanger-Lapointe (University of Iceland), Ingibjörg Svala Jónsdóttir (University of Iceland), Toke Hoye (Aarhus University), Sasha Sokolov (Russian Academy of Sciences), Johan Olofsson (Umeå University), Emmanuel Pagneux (Agricultural University of Iceland), Bryndís Marteinsdóttir (Soil Conservation Service of Iceland), Kari Anne Bråthen (UiT The Arctic University of Norway), Dorothee Ehrich (UiT The Arctic University of Norway), Jón Guðmundsson (Agricultural University of Iceland), Bruce Forbes (University of Lapland) and Timo Kumpula (University of Eastern Finland).
As part of the TUNDRAsalad project, Mathilde Defourneaux developed her PhD project focusing on the effects of changing herbivore communities in Iceland. Mathilde’s PhD, titled “The impacts of spatio-temporal shifts in vertebrate herbivore communities on the functioning of the Icelandic tundra” is available here.
You can read more about the TUNDRAsalad project here.
Publications from the TUNDRAsalad project
DEFOURNEAUX, M., BARBERO-PALACIOS, L., SCHOELYNCK, J., BOULANGER-LAPOINTE, N., SPEED, J.D.M., BARRIO, I.C. (2025) Capturing seasonal variations in faecal nutrient content from tundra herbivores using Near Infrared Reflectance Spectroscopy. Science of the Total Environment 981:
179548 https://doi.org/10.1016/j.scitotenv.2025.179548
BARBERO-PALACIOS, L., BARRIO, I.C., GARCÍA CRIADO, M., KATER, I., PETIT BON, M., KOLARI, T.H.M., BJØRKÅS, R., TREPEL, J., LUNDGREN, E., BJÖRNSDÓTTIR, K., HWANG, B.C., BARTRA-CABRÉ, L., DEFOURNEAUX, M., RAMSAY, J., LAMERIS, T.K., LEFFLER, A.J., LOCK, J.G., KUOPPAMAA, M.S., KRISTENSEN, J.A., BJORKMAN, A.D., MYERS-SMITH, I., LECOMTE, N., AXMACHER, J.C., GILG, O., DEN HERDER, M., PAGNEUX, E.P., SKARIN, A., SOKOLOVA, N., WINDIRSCH, T., WHEELER, H.C., SERRANO, E., VIRTANEN, T., HIK, D.S., KAARLEJÄRVI, E., SPEED, J.D.M., SOININEN, E. (2024) Herbivore diversity effects on Arctic tundra ecosystems – a systematic review. Environmental Evidence 13(1):6 https://doi.org/10.1186/s13750-024-00330-9
DEFOURNEAUX, M., BARRIO, I.C., BOULANGER-LAPOINTE, N., SPEED, J.D.M. (2024) Long-term changes in herbivore community and vegetation impact of wild and domestic herbivores across Iceland. AMBIO 53(8): 1124–1135 https://doi.org/10.1007/s13280-024-01998-6
BOULANGER-LAPOINTE, N., ÁGÚSTSDÓTTIR, K., BARRIO, I.C., DEFOURNEAUX, M., FINNSDÓTTIR, R., JÓNSDÓTTIR, I.S., MARTEINSDÓTTIR, B., MITCHELL, C., MÖLLER, M., NIELSEN, Ó.K., SIGFÚSSON, A.Þ., ÞÓRISSON, S.Þ., HUETTMANN, F. (2022) Herbivore species coexistence in changing rangeland ecosystems: first high resolution national open-source and open-access ensemble models for Iceland. Science of the Total Environment 845:157140 https://doi.org/10.1016/j.scitotenv.2022.157140
SOININEN, E.M., BARRIO, I.C., BJØRKÅS, R., BJÖRNSDÓTTIR, K., EHRICH, D., HOPPING, K.A., KAARLEJÄRVI, E., KOLSTAD, A.L., ABDULMANOVA, S., BJÖRK, R.G., BUENO, C.G., EISCHEID, I.,, FINGER-HIGGENS, R., FORBEY, J.S., GIGNAC, C., GILG, O., DEN HERDER, M., HOLM, H.S., HWANG, B.C., JEPSEN, J.U., KAMENOVA, S., KATER, I., KOLTZ, A.M.,, KRISTENSEN, J.A., LITTLE, C.J., MACEK, P., MATHISEN, K.M., METCALFE, D.B., MOSBACHER, J.B., MÖRSDORF, M., PARK, T., PROPSTER, J.R., ROBERTS, A.J., SERRANO, E., SPIEGEL, M.P., TAMAYO, M., TUOMI, M.W., VERMA, M., VUORINEN, K.E.M., VÄISÄNEN, M., VAN DER WAL, R., WILCOTS, M.E., YOCCOZ, N.G., SPEED, J. D. (2021) Location of studies and evidence of effects of herbivory on Arctic vegetation: a systematic map. Environmental Evidence 10:25 https://doi.org/10.1186/s13750-021-00240-0
Despite the importance of herbivory for ecosystem functioning, the direct assessment of plant-herbivore interactions is still not part of current monitoring efforts. Our preliminary analysis of Svalbard reindeer diet revealed considerable discrepancy in the estimated proportion of ingested plant species using micro-histology of plant fragments, compared to modern DNA metabarcoding and stable isotopes methods, thus calling for the rigorous assessment of these three methods.
The PIECEMEAL project, led by Stefaniya Kamenova at the Norwegian University of Life Sciences (NMBU) was funded by the Svalbard Science Forum, and brought together six international experts from Norway, France, Spain, Finland, USA and Sweden in each of the three diagnostic techniques, with colleagues in both the Norwegian Polar Institute in Ny-Ålesund and UNIS in Longyearbyen. Taking advantage of a rare opportunity of working on the same physical samples, they were able to provide a cost-efficient and ultimately non-invasive way, to reliably characterise Svalbard reindeer diet. These data allow better mechanistic models of both reindeer population growth, Svalbard plant community dynamics, and tundra ecosystem processes, as the climate continues to warm. Finally, by comparing three key methods for identifying the plant ingested by reindeer, our combined network and workshop project led to the establishment of a “gold standard” toolbox for diet analysis, relevant not only to Svalbard reindeer, but also to large herbivores in general.
Following up earlier HN work on the patterns and drivers of herbivore diversity across the Arctic (Barrio et al. 2016, Speed et al. 2019), James Speed and MSc student Jesus Adrian Chimal Ballesteros assessed phylogenetic and functional diversity of both Arctic and boreal herbivore species. Their work examined the presence of clusters of herbivore communities in functional and phylogenetic space, and tested whether these relate to biome transitions or biogeographic transitions. This work helps understand the likely implications of northward movement of herbivore species from the boreal to Arctic biomes.
Adrian successfully defended his MSc thesis in 2019, and the full text is available here. The results of this work were published in Global Change Biology:
SPEED, J.D., CHIMAL-BALLESTEROS, J.A., MARTIN, M.D., BARRIO, I.C., VUORINEN, K.E., SOININEN, E.M. (2021) Will borealization of Arctic tundra herbivore communities be driven by climate warming or vegetation change?. Global Change Biology, 27(24):6568-6577 link to publisher
Systematic maps are a tool that allows synthesizing and integrating information to assess what (and how much) has been studied where. The aim of this project was to assess the status of knowledge and current evidence on the effects of herbivores on vegetation in the Arctic. Using a systematic map we were able to identify which environmental contexts can be understood with the current evidence and for which we do not have enough information.
Systematic maps are conducted as two-stage processes: first, a transparent protocol is defined to conduct an unbiased systematic search of evidence, and then the actual systematic map is produced. The first phase of the project received funding from the FRAM Centre and resulted in the publication of the protocol in the journal Environmental Evidence. The next step used the protocol to develop the systematic map. This step was a massive coordination effort led by Eeva Soininen. A large number of collaborators have been involved in this step, which was published in the journal Environmental Evidence:
SOININEN, E.M., BARRIO, I.C., BJØRKÅS, R., BJÖRNSDÓTTIR, K., EHRICH, D., HOPPING, K.A., KAARLEJÄRVI, E., KOLSTAD, A.L., ABDULMANOVA, S., BJÖRK, R.G., BUENO, C.G., EISCHEID, I., FINGER-HIGGENS, R., FORBEY, J.S., GIGNAC, C., GILG, O., DEN HERDER, M., HOLM, H.S., HWANG, B.C., JEPSEN, J.U., KAMENOVA, S., KATER, I., KOLTZ, A.M., KRISTENSEN, J.A., LITTLE, C.J., MACEK, P., MATHISEN, K.M., METCALFE, D.B., MOSBACHER, J.B., MÖRSDORF, M., PARK, T., PROPSTER, J.R., ROBERTS, A.J., SERRANO, E., SPIEGEL, M.P., TAMAYO, M., TUOMI, M.W., VERMA, M., VUORINEN, K.E.M., VÄISÄNEN, M., VAN DER WAL, R., WILCOTS, M.E., YOCCOZ, N.G., SPEED, J. (2021) Location of studies and evidence of effects of herbivory on Arctic vegetation: a systematic map. Environmental Evidence 10:25 link to publisher
Check out also the nice lay summary here.
The project led by James Speed, started in 2017 and investigated the interactive effects of herbivory and climate on northern ecosystems. The DISENTANGLE project was hosted by the NTNU University Museum, Norwegian University of Science and Technology. Partners included Isabel Barrio (Agricultural University of Iceland), Alison Hester (James Hutton Institute, Scotland), John-Arvid Grytnes (University of Bergen), Jean-Pierre Tremblay (Université Laval) and Gunnar Austrheim and Mike Martin (NTNU).
There are three components to the project, the first used dendroecology to tease apart the effects of herbivory and climate on woody plant growth in boreal and tundra ecosystems, and long-term plant community data to investigate the herbivore and climate impacts on vegetation change. Katariina Vuorinen, a PhD student at the NTNU University Museum led this work (Vuorinen et al. 2022). The second aspect of the project investigated how herbivores affect the distribution of plant species. The third section of the project mapped out herbivore communities across the boreal and tundra biomes (Speed et al. 2021).