I have moved into a new house this spring and have bees (some sort of bumble bee) living in the bird box. I was quite happy with them, but over the last week they are getting to be(e!) a pain- everytime I go to the shed or try and garden near the nest one or two of them will buzz about or fly into my head... have not been stung, but am wanting to get rid of them.

Does anyone know of a group or organisation that will come and collect them?

Try googling the Beekeeper's Association. I posted a link to it on another thread about random infestations of bees last week sometime. They might get a local beekeeper to come and take them away.

Bees are dying out although a protected species so they might be glad of new stock.

Bumble bees do go into bird houses, these are not honey bees, that have around 10 to 50,000 in a hive. Your bumbles have about 20-30 bees, I don't think a bee keeper would want these or can help you. Bees will buzz you and hit into you as a warning, they will go in the winter and the queen will hibinate, the rest will die. Try and light some paper and smoke around the nest before going near them. This makes them think there is a fire and will go and eat the honey sort rather than buzzing you. good luck.

There are many many types of British Bumble bee and a colony will/can get to 100-200 bees in the height of Summer, the lay lots of new queens is Autumn that go off and hibernate and the rest die out then.

Bees buzz when you hit them? smoke does not have the same effect on BB's as it does with honey bees and you are only likely to make them more aggressive with this approach - different species sorry.

Bumble bees offer nothing to beekeepers they deal with honey bees, sorry but they are separate species entirely.

Yes there are people that can help, we are removing a bird box later this month for someone with the same issue.

Jez