The 2025 meeting of the International Tundra Experiment (ITEX) was held last 29 September to 3 October 2025 in Nordens Ark, a wildlife park dedicated to the conservation of endangered species in Gothenburg, Sweden.
Several NordBorN researchers participated in the meeting, including Mariana Garcia Criado, who presented her recently published paper on plant borealization across the Arctic. Alejandro Salazar presented his work on biocrust-plant interactions at an ITEX site in Iceland.
Last week, Beatrice Trascau and James Speed visited Mariana García Criado at the Centre for Ecological Research and Forestry Applications (CREAF) in sunny Barcelona, Spain.
Mariana reports back from an intensive week of work:
We spent the week working on a NordBorN project with the aim of characterizing boreal and tundra plant species’ functional trait spaces. The workshop was a success and we are currently finalising the analyses and starting to write the manuscript. The idea for this project came up during the first NordBorN meeting in Iceland in 2024, so we are very excited to share some updates with you soon!
During their visit, Beatrice also presented her PhD work to the Global Ecology Unit at CREAF.
The spread of the beaver (Castor canadensis) into the Arctic tundra is a textbook example of the process of borealization. A new study by Ken Tape at the University of Alaska Fairbanks and James Speed at the Norwegian University of Science and Technology and a member of the NordBorN network, shows how temperature is a crucial factor determining the distribution of beavers and their impact on the whole ecosystem through dam building across the Alaskan tundra.
Temperature drives an increase in suitable habitat for beavers from 15 000 km2 in the early 20th century, to 30 000 km2 at present, while future climatic warming is projected to increase the potential suitable habitat to between 100 000 and 150 000 km2 by 2090.
Such a dramatic increase in distribution of an ecosystem engineering species is likely to have dramatic impacts on the future state of the tundra.
The paper was recently published in Environmental Research Letters, and has been featured in Science.
Reference: Tape, K. D., & Speed, J. D. (2025). Predicted expansion of beaver pond distribution in Arctic Alaska, 1910–2090. Environmental Research Letters, 20(9), 094009. 10.1088/1748-9326/adeba2
The picture shows a beaver modified habitat in Alaska (photo: Ken Tape, University of Alaska Fairbanks)
