I have found Bee Go to be very effective. You don't have to use a vast quantity: a few drops on a blob of cotton wool eased into the cavity behind them will get them out. A bit of wire, a cane or even a fishing rod might assist. Sometimes it might be helpful to drill a small hole in the wall to gain access beneath the cluster.

On one occasion I was called to a house where the owner thought he had bees in his wall.  He did, but only scouts looking for a new home.  A drop of Bee Go on some cotton wool strategically placed soon changed their mind. The owner, getting a whiff of the Bee Go, likened it to the aroma of the Parmesan cheese he was grating on his children's pasta.

Unfortunately Bee Go seems no longer to be obtainable in the UK as, understandably, it is not allowed on aircraft and people seem to have forgotten how to ship things by ship.

Chris

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