Reindeer interactions from plants and birds to humans: balancing the odds of climate change

We use DNA from plant and lichen remains to identify actual content of reindeer diet and study species and human interactions of the reindeer - one of the surviving remnants of the Ice ages in the Arctic, with high cultural and economic value for indigenous residents. While reindeer husbandry is relatively small in terms of economics at a national scale, it is deeply rooted in history, culture and provides for traditional subsistence way of life of indigenous peoples. Taking a circumpolar perspective, degradation, and loss of pasture lands, combined with the consequences of climate change, present substantial challenges to the future of this "small industry". Using DNA metabarcoding we analyzed geographic, climatic, and seasonal patterns of reindeer diet variation in different socio-economic settings of four arctic regions (Svalbard: wild reindeer, no management, no migrations, no blackflies, time series data available; Norway (Finnmark): semi-domesticated reindeer, long traditions; Russian Arctic (Yamal): both wild and domestic reindeer, long traditions; Canada and Alaska: wild populations of caribou and recently introduced reindeer herding. We studied diet overlap and inferred trophic interactions with other herbivore species in the North: ptarmigans (Lagopus spp.), hares (Lepus timidus), moose (Alces alces) and rodents. We aimed to test whether reindeer diet changes correlate with warmer/longer summers or variation in population density. We integrated this ecosystem-based information with local knowledge of reindeer herders to perform satellite image analyses for habitat suitability modelling for current (1998-2016) and future (2070) pastures in Finnmark. It was found that the area of mountain birch forest in Finnmark has been expanding as well as barren land area with very sparse vegetation at higher elevations of summer pastures. The area of mountain heath and shrubs has been decreasing. In terms of reindeer habitat suitability there are no significant changes happening. However, the unsuitable area is slowly expanding. If these patterns behave according to the model predictions, then they might have significant consequences for the state of summer pastures and the herds. Our interdisciplinary project team included young scientists and students and produced four MSc theses and contributed to one PhD thesis. Several manuscripts and datasets are now being prepared. This research work will be continued within the framework of ArcEcoGen-Arctic Ecosystem Genomics a newly established Aurora Centre of excellence at the UiT.

Anticipated outcomes and impacts - from the grant application form According to the grant application the anticipated impacts, relevance, and benefit to society: The project will contribute by (i) providing detailed knowledge on trophic interactions in Arctic ecosystems which form the basis of ecosystem structure and functioning and its services to society. We contribute to adaptive management and governance solutions for sustainable reindeer husbandry on the local level, based on integration of traditional knowledge and new DNA metabarcoding diet and diet-overlap data for reindeer/caribou - one of the last remnants of the Beringian megafauna in the Arctic, keystone species, with high cultural and resource value for indigenous residents. (ii) The development of new barcoding systems suitable for degraded DNA can also be directly used for other purposes such as biodiversity assessment of modern and paleo-ecosystems and in food industry by identifying ingredients in processed food. o Actual and potential outcomes and impacts based on the project results Along with climate change, herbivory is considered a main driver of ecosystem change in terrestrial arctic environments. The results regarding plant-herbivore interactions will expand our knowledge on mechanisms that are involved in individual/ population/species level sensitivity of diet-host nexus to changing environments. Several project outcomes, in particularly the development of multi-locus DNA metabarcoding of dietary composition in animals and indicators of pasture quality will be directly contributing the objectives of the “Climate and environment” scientific priority areas, stating: “to generate more knowledge about the adaptive capacity of ecosystems and their resilience to external pressures”. “Promoting creative thinking and innovation in polar research”: (i) We expanded, adopted and adapted state-of-the-art methodology from interviews and participatory mapping to remote sensing and GIS-modeling to be integrated together with genetic research tools to study non-model species and natural ecosystems; (ii) We generated new genetic data which can be used to develop sustainability biomarkers of reindeer health and nutrition and pasture quality; (iii) Our lab-bench protocols can be make into the portable field set up to facilitate application for both research and management. “Ensuring continuity in polar research by recruiting young polar researchers”: Our project employed many young researchers: MSc students, a PhD and a postdoc. They were involved in all project tasks during design and implementation. Together we developed career plans to ensure that their research experience at REININ will provide a solid foundation to successful career in research or nature management.

We generate DNA based diet data and study species and human interactions of the reindeer - one of the last remnants of the Beringian megafauna in the Arctic, keystone species, with high cultural and economic value for indigenous residents. While reindeer husbandry is relatively small in terms of economics at a national scale, it is deeply rooted in history, culture and provides for traditional subsistence way of life of indigenous peoples. Taking a circumpolar perspective, degradation and loss of pasture lands, combined with the consequences of climate change, present substantial challenges to the future of this "small industry". Using DNA metabarcoding we analyze geographic, climatic and seasonal patterns of reindeer diet variation in different socio-economic settings of four arctic regions (Svalbard: wild reindeer, no management, no migrations, no blackflies, time series data available; Norway (Finnmark): semi-domesticated reindeer, long traditions); Russian Arctic: both wild and domestic reindeer, long traditions; Canada and Alaska: wild populations of caribou and recently introduced reindeer herding). We will study diet overlap and infer trophic interactions with other herbivore species in the Arctic, such as geese, ptarmigan (Svalbard) and rodents (Finnmark). Our study will test whether reindeer diet changes correlate with warmer/longer summers or variation in population density. We integrate this ecosystem-based information with socio-economic data and local knowledge of reindeer herders to apply adaptive governance for developing co-management actions and implementation of alternative reindeer husbandry practices and mitigation measures for climate and/or land use change. Our interdisciplinary project team consists of national and international leading experts in several fields and young scientists. The project will be closely linked to the PhyloAlps, NorBOL and REINCLIM projects to ensure immediate access to new developments in metabarcoding/bioinformatics.