A high-mountain relict Papaver occidentale – history and perspectives of a rare species of alpine screes

Papaver occidentale is a narrowly distributed taxon from the P. alpinum group, which occurs only on isolated north-exposed calcareous screes of the Western Prealps (Switzerland and France). Genetic analyses of its all known populations revealed presence of several distinct lineages and indicated a complex history of this taxon which may have involved both postglacial recolonisation from lower-elevation, external refugia, and likely in situ survival of local populations throughout the last glacial period. In turn, species distribution modelling (SDM) performed for this patchily distributed species based on fine-scale data collected in the field indicated a substantial decrease of climatically and topographically suitable areas and high extinction risk for P. occidentale under all climatic scenarios considered. Accordingly, our case study warns that local environmental buffering of large-scale climate change, often inferred for the high-mountain flora, may be very limited in specialised taxa of patchy environments such as screes. Studies on P. occidentale were carried out as part of a recent project by Professor Gregor Kozlowski from the University of Fribourg (Switzerland), conducted in cooperation with Dr. Michał Ronikier from our Institute, who specializes in high-mountain biota research.

More about the research results can be read in the articles:

Pittet L., Fragnière Y., Grünig S., Bétrisey S., Clément B., Gerber E., Ronikier M., Kozlowski G., Parisod C. 2020. Genetic structure of the endemic Papaver occidentale indicates survival and immigration in the Western Prealps. Alpine Botany 130: 129–140. DOI

Fragnière Y., Pittet L., Clément B., Bétrisey S., Gerber E., Ronikier M., Parisod C., Kozlowski G. 2020. Climate change and alpine screes: no future for glacial relict Papaver occidentale (Papaveraceae) in Western Prealps. Diversity 12: 346. DOI

Papaver occidentale – the plant under study.
Photo: Gregor Kozlowski.

Papaver occidentale in the alpine landscape.
Photo: Gregor Kozlowski.