After my observations last Friday I did a bit of Googling on the subject of Bumblebees apparently sleeping on or in flowers overnight.. It turns out that some do, especially males towards the end of the breeding season when the females have no use for them. As for my observation that they sometimes seem to freeze while feeding on flowers. Again this can and does happen. They need an internal body temperature of 30C to be able to fly and when cold they will stop and appear to shiver as we do to raise their temperature. The day I was watching them the air temperature was about 14C so the bees were having their work cut out to get enough nourishment to enable them to maintain their body temperature. In fact it will take a bee about 5 minutes to raise its temperature in those conditions.
A good source of information can be found HERE at bumblebee.org.
How to stop Bobby using part of the garden.
Yesterday I noticed that Bobby was avoiding visiting his favourite barking position in the garden. It seems that he wouldn't use the path as there was a dead male Blackbird blocking his route. The bird must have flown in to the wall of a shed, probably during one of the many altercations they have over territory. Once the offending corpse had been removed Bobby was quite happy to use all his garden again.
7 hours ago