Wasps are starting to make an appearance around the hives.
To keep the pesky invaders out:
Reduce the entrance size of the hive, probably opened fully during the recent hot weather, to give the bees a smaller area to defend.
Put out wasp traps, these can be bought or easily made with a jam jar with a hole made in the lid or from a plastic drinks bottle as shown. Jam attracts wasps, but not bees. Do not use honey in the bait of course.
Be tidy, keep rubbish away from the apiary which could attract wasps and other pests!