This is all very interesting. I had no idea there were so many species of bumble bee. We have big ones and little ones but I hadn't given thought (or noticed) any others. I like them a lot (even the one which stung me a couple of months ago) and will take more notice now, or when a new batch arrives in our spring.
Because of what seems to be a world-wide shortage of honey bees, many orchardists and market gardeners, especially under glass, are using bumble bees to pollinate for their crops. We are able to buy a small colony in a box which is positioned in a suitable place and the bees live there and do their work.