BUND Nature Conservation wants to record bumblebee sightings twice a year and always at the same time. The bumblebees have been reported since March 20th to April 9th.
The best chances for good photos are in meadows and in beds with blue or purple flowers. In spring, flowering fruit trees and berry bushes are also very popular with the fat bumble bees. Whoever finds the most bumble bee species during the project period can win something. More information here.