I visited the apiary where Colony 11 is sited this evening. They are still angry 24 hours after I reorganised the hive in a failed attempt to extract the lid of a nucleus box. They bumped against head when I came within 5m. When I had my veil on and got closer they went into attack behaviour (high pitched buzzing; staying in one place on the veil; jabbing movements with their abdomens). I hope that they calm down and don't spend the season being angry.
The bees were angry today. They attacked. They followed. They found the gaps around my shoes and stung my feet. They stung through my gloves. They were cross.
Hungry bees are angry bees. The bees are hungry so I'm feeding them.
There may be other reasons for them being so defensive.