Just got back from Avon gorge and an abortive attempt to climb Dawn walk. There is a wasp nest on the approach to the climb, in some rotten wood on the ground, about 5m away from the base of the route. I managed to get past it without noticing but my partner was stung multiple times.
If you're planning on climbing Dawn walk, or any of the routes starting from breakfast ledge (Pink wall direct, Lich gates, etc.) then take care on the approach!