Why do the bumble bees in my back yard keep dying?

I have a hive of bees in my back yard that live under my porch. It doesn't bother me at all as I've never been stung and they pretty much never come near me. However, in the last two or three weeks, every time I've gone outside there have been dead or dying bees on the floor. I went out today and there was around 20 dead or on their last legs bees all over the floor. I know that bee conservation is a big thing now, and I was just wondering why they were dying and so close to the nest?Why do the bumble bees in my back yard keep dying?
There is a mite going round at the moment killing bees. You'll probably find the reason they're all lying underneath the hive is the dead bodies have been thrown out by the other bees. Have a wee look at their tails and you can actually see the mitesWhy do the bumble bees in my back yard keep dying?
There are two things that could have killed them. If there's a orchard nearby the people working there spray the trees with insecticide and the wind would blow the spray over peoples gardens and that would certainly cause their deaths.





The other would be big hornets which attack in great swarms,and the hornets are the bees natural enemy. There was a Japanese bee keeper who lost quite a lot of his bees because hornets killed them
The bees are most likely dying because of the sudden changes in the worlds climate. Bees are not use to these changes and so die. If all the bees were to die in the world mankind could only exist for 4 yaers. Last year over 90% of bees had disappeared and according to the mayans the world is set to end in 2012.
They are very likely the drones, the males. they do nothing but hang round and wait to mate with a new queen. At a certain point in the season, usually around now, the workers kick them out to die or actually sting them to death, because there will be no swarm rising this late in the summer.
bee flu
I don`t know what species they are, or where you live, but this could be entirely natural.





The nest would have started with a queen, who lays eggs and starts a new colony. The workers that are produced help build the nest, and bring food for the brood (babies!)





If the queen dies, or moves away, then the workers have lost their purpose and have no work to do...so they can die of old age around the hive....and there are no new bees being produced as the queen has gone. Bees do not live that long.





For example, we are often bothered by wasps in late summer...but earlier on in the year, although there are loads, they don`t bother us much. This is because earlier in the year the workers are busy bringing back loads of caterpillars and similar food for the young brood.





But after the nest`s work is done, these worker wasps have no purpose, and so are attracted to sugary things like fizzy drinks and suddenly become a nuisance, before dying.





I would need to know the species before being sure, and there are other possibilities, such as insecticide being used locally, or a predator (such as some hornets having attacked the nest), as well as disease being a problem.





BTW...many bee and wasp species don`t return to the same place twice, as the old site will have built up disease, so you are unlikely to have a nest there when the next season starts.





Beechnut.