You are obviously a caring beek; there's not many that provide a door to the field, so the bee's can close it to keep warm in the Winter - good thinking!
What time of day was the shot taken? I seem to get an awful lot of bees out around lunchtime when the weather is good. I assume it is young bees orienting, they hang out in a cloud in front and circle around the garden, I love sitting up by the hive just watching. They haven't sent me on my way yet.