Studying plant seasonality with the help of rangers

Nature park rangers are out in nature every day and are also directly in touch with people. That is why a team of researchers from the Swiss Federal Institute for Forest, Snow and Landscape Research WSL invited them to collaborate in observing the seasonal processes in nature and communicating them to the park visitors.
"Customer contacts" are one of the core competences of the rangers. (Photo credit: K. Meller)

Nature park rangers are ideal partners for bringing research and the public together. On the one hand, they observe plant and animals in their park and take care of their preservation. On the other hand, they meet visitors, organize excursions and seminars to educate them about nature and nature conservation. The WSL ecologists Frederik Baumgarten and Yann Vitasse make use of this double function in the PhenoRangers knowledge transfer project supported by the Swiss National Science Foundation (Agora Project).

”This is a win-win deal,” says Vitasse, who studies seasonal changes in plants at WSL, for example the onset of flowering or autumn colouring. "On the one hand, the rangers help us to monitor these phenomena over the long term and at many sites with different climates. On the other hand, we provide them with educational and interactive tools to pass on knowledge to park visitors about environmental issues and changes induced by climate change,” he says.

Vitasse's scientific discipline is called phenology. With climate change, it has gained relevance, because temperature largely affects plant and animal cycles which can potentially cause seasonal mismatches between interacting species. For example, terrestrial insects are generally very sensitive to temperature and start their cycles earlier and earlier, while some migratory birds that feed on them may rather rely on day length to return after winter.

Swiss rangers observe how nature changes throughout the year, which is called phenology. (The Video exists in German, French and Italian)

Discover the environment

The project meets with great interest among the rangers. "When I show examples like the discrepancy between insects and migratory birds during my guided tours, it really impresses the visitors," says Silva Lanfranchi, a ranger in the Glaubenberg marshland in Obwalden. The PhenoRangers project makes changes in nature and biodiversity visible, not only in nature parks but also in the city, she says. So far, 24 rangers in German-speaking and French-speaking Switzerland are participating.

As part of the PhenoRangers project, which will run from 2021 to 2024 and likely longer, scientists have developed a variety of interactive and educational tools for rangers to interact with the public on the topic of phenology and climate change. For example, a web application ( has been available for the rangers since 2022 with a partnership with GlobeSwiss. This platform is available for all persons willing to record phenological observations in Switzerland but was further developed to host all new observations from the rangers.

This spring, new materials for interactive site visits were added: a YouTube video about the project, a flyer, podcasts in which the scientists present the project and a set of laminated maps showing animal and plant phenomena throughout the year. Game ideas are suggested to help the rangers communicate the seasonal observations during guided tours.