Phenology, landscape utilisation and monitoring of bumblebees
The most bumblebee-rich landscape elements in this study were pastures, wood verges and field verges, where 70% of all observations were made. If these landscape elements disappeared due to agricultural intensification it would have serious consequences for bumblebees in this area. These landscape elements alone are, however, not enough to support viable bumblebee populations. The results points out the importance of a diverse landscape with different landscape elements, because bumblebee species prefer partly different landscape elements and all species showed a clear seasonal variation in habitat preferences. Therefore it is important to preserve and protect even less bumblebee-rich landscape elements.
This study has shown that bumblebees can forage under poor weather conditions and that they have clear preferences in terms of forage plants and habitat requirements which facilitates monitoring. In order to detect a significant change in abundance, large scale monitoring with many visited sites is needed. To detect a 50% change in abundance of B. pascuorum, the most common species, 295 sites must be monitored. It is recommended that the visit each season is carried out at the beginning of the summer due to lower variation in abundance earlier in the season.
Responsible for this page: Agneta Johansson
Last updated: 05/15/06