Looking for Cowslips

In spring, scientists invite everybody around Europe to take part in the biggest cowslip observation campaign “Looking for Cowslips”. The aim of the project is to examine the patterns of flower morphological traits (i. e. heterostyly) in cowslip populations all across Europe using a citizen science approach. The citizen science project “Looking for Cowslips” was carried out already in 2019 and 2020 in Estonia and Latvia. Within the frames of this campaign, we obtained heterostyly data from > 150 000 cowslip individuals in each year of 2019 and 2020 in Estonia (and Latvia). Since 2021 we are also asking enthusiastic citizen scientists across the EU to participate and contribute, with great success. Data originating from the campaign provides unprecedented insight into the patterns of heterostyly following the loss of semi-natural grasslands.

Participants are expected to observe the patterns of heterostyly in cowslips. The cowslip (Primula veris) is a heterostylous plant – it means that the plant can have one of the two types of flowers. These different types of flowers are called S-morphs (short-styled) and L-morphs (long-styled). In short-styled cowslips (S-morphs), five anthers are visible in the flower when looking from above, and in individuals with L-type flowers, a green dot in the middle of the flower (the stigma) is visible. Normally in cowslip populations, the frequency of these different types of individuals is more or less equal. Imbalance reduces a plants’ opportunities to find a suitable mate for reproduction, which impedes pollination and the exchange of genetic material. This, in turn, reduces a plants’ vitality. The cowslip’s regular habitats – traditionally managed grasslands – have become increasingly rare in the contemporary landscape. The disappearance of grasslands causes decline in plant populations depending on grassland habitats. A massive decline in cowslip populations can cause substantial imbalances in the frequency of L- and S-morphs to the extent that one of those types completely disappears from the habitat. That is precisely the kind of a possible shift in the balance between the L- and S-morphs caused by changes in the landscape that we want to study – with your help. An observation takes about 30 minutes. When possible, one should observe the flowers of 100 cowslip individuals. Look at the flower and report whether you see five anthers (S-morph) or one stigma (L-morph). Find the time, breathe some fresh air, and help scientists with their work!

For more information, check out our webpage www.cowslip.science.

To find out more about the interesting findings from the first year of the campaign, you can read the article at: https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2745.13488.

You can contact us at This email address is being protected from spambots. You need JavaScript enabled to view it. for further questions.