Bees nesting in cavity walls

[EarthAngel]

Ladies and Gentlemen.

Approx two weeks ago, me and my boyfriend noticed bees flying to a hole in the mortar in our rear house wall, we considered blocking it off but were worried that if we did, the bees already inside would get trapped and die, being animal lovers, this was not something that we wanted to do, we have, however, noticed that the bees seem to be blocking off that entrance, we are a little perplexed as to why they would feel the need to do this, we do not actually know if there is a nest somewhere, my boyfriend seems to think that it could be that the bees have a nest in the loft and have found an alternate entrance, we have not checked the loft yet but plan on doing that soon.

would anyone have any answers for us ???? :)

[G4WIL]

MHHHH??
these could be masonary bees :). if so they aren't social insects and so there will be few in number . I suspect that "they've blocked the entrance" means the bee using the hole has filled it with An egg followed by some food followed by a leaf, (this could indicate a leaf cutter bee, )again a none social variety :).
First try to establish what kind of bee are they, are they about in large numbers ie a few dozen milling about or the odd one .
Should they prove to be any other kind of bee than a honey bee, then the message is "Please leave them alone, and come Autumn, they will disappear :). that is then the time to cement the hole up.

regards

[Chris]

Mason bees typically excavate tiny grains of sand and mortar, especially in old buildings. They are are solitary bees, but if you get a number of them using the same patch of brickwork, it can look as if they are living as a colony.

Honeybees look similar to mason bees, but if a honeybee colony had moved into your cavity wall you would typically get hundreds or even thousands of bees.

Suggest you have a search for mason bees on the net. They are harmless insects that usually go completely unnoticed. And they are best just left alone.

[EarthAngel]

thankyou for your prompt response to my question as I was getting a little worried, i have spoken to my boyfreind and we will leave it well alone. :)

[ChrisBroad]

MHHHH??
"Please leave them alone, and come Autumn, they will disappear :). that is then the time to cement the hole up.

regards

That would be good advice for bumble bees but not mason bees which is what they sound like. They seal in their grubs with a plug of mud or leaves (depending on variety). The grubs pupate and hatch next spring, biting through the plug. But cementing them in will doom them.
Mason bees will not damage buildings, they just use existing cavities or find a way through loose material. They also like to nest in the ends of bamboo canes.

[G4WIL]

Hi Chris,
thanks for the update (where ignorance is bliss :( )
I didn't realise that the pupation period was that long for mason bees :o.

I hope earth angel re-visits this thread and forgoes any permanent hole blocking.
If not then I hope that she takes berky's advice and googles "mason bee"