Wasps everywhere but none appear to be getting inside

My hives are surrounded by at least half a dozen wasps which want to rob them. They zig-zag in front of the entrance; they crawl in under the Varroa screen; they wait at the edges and drink from the water tray. They want the honey but they can't get in.

All of the hives in central Oxford have small doors and strong guards. Three of the four have at least 20 bees visible on the outside of the hive entrance. One hive had fewer visible but appeared to be just as effective at guarding.

Having so many Wasps around makes it hard to open the hives. Once robbers get in they are more likely to return. They're as happy to gain entry from the roof as through the door. I think that they're also more likely to successfully return and re-enter the hive because they smell of the honey from that hive. Robbing can become a storm which only abates when the hive is moved out of range of the robbers. That's a lot of work just for a look inside.

Robbers notwithstanding, I took a very quick look inside the hives in central Oxford to check that none had run out of space. They all have sufficient space for the moment. They are also all dropping pollen, which suggests they're still laying and there  is forage for them. There is plenty of door activity at all the hives. I found no Varroa mites on the base board. I was some evidence of Wax Moth and some evidence of new comb.

Colony 1 in Headington is also faring well. There are some wasps, but fewer than in central Oxford. There is pollen being dropped and plenty of door activity.