Butterfly Survey 2025 - 'How To' guide

Butterfly survey 2025 - 'How To' guide

Download your guide (English, Deutsch, Français, српски) below

Choose a field. Your chosen field could be covered by wheat, rye, corn, rapeseed, potatoes, apples, a fallow land (unsown or unploughed), grassland, olives or a vineyard.
Choose an observation site at the border of the field. It can be any border between the selected field and one type of adjacent habitat, such as hedges, buffer-strips (vegetation between fields), flower strips, a forest or woodland, or another field. It should be easily accessible. A meeting point between arable land and grassland may also be selected.
Select a second, adjacent sampling site if possible, so that the first site is at the border between the field and an adjacent habitat, while the second one is inside the field (at least 50m from the field border). Each observation site should ideally be 20×25m (option 1), 10×50m (option 2) or 5×100m if the adjacent habitat is too narrow (see figure). The exact sampling area could be adjusted where needed.

Between April and September, i.e. during the main ‘flight season’ for butterflies.
At least three times in the season, though more is better (Once in two weeks is optimal – some people do it weekly!).
On a warm, sunny and windless day. Above 13°C on sunny days, 17°C on cloudy days.
Between 10:00 and 17:00, when butterflies are most active. In summer one can start earlier.

Make sure you ask permission from whoever owns your chosen field.
When walking in the field, limit the damage to the crop by walking between crop rows as much as possible.
If you can’t obtain permission, sample only the area at the border between the field and the adjacent habitat, without entering into the field.

Click on your language for instructions on how to count butterflies.