It was looking like a bumper crop of walnuts this year - but woke up this morning to find every single one gone. Grrrr.
Interesting the swallows departed overnight - but I don't think they're the culprits 😒
I always think there's a missing instruction with these types of guards. If a wasp or two find their way in and out then they leave a trace of honey which can be an attractant for other wasps. Easily solved of course by removing the front cover and quick wipe with a cold damp cloth.