General Schvantzkoph wrote:
Doug Freyburger wrote:

Let's see if I have the likely chain of events right. Bumble bees are a
wild pollinator. Honey bees are a domesticated pollinator. Because
honey bees are domesticated they are widly used. Because honey bees are
widely used a lot of them have gone ferral. Ferral honey bee colonies
compete with bumble bees. That competition has reduced their
population. No wonder I know of folks who will destroy any ferral honey
bee nest they find yet I also know of bee keepers who will gather any
ferral nest and use it to reduce inbreeding in their commercial bee
stocks.

Honeybees have been used for centuries, if competition from them were the
cause for the decline in bumblebees it would have happened a long time
ago. That's not to say that there is no relationship. If the problem is a
disease then domestic honeybees might very well be the vector that's
spreading the disease to wild bees. Domestic bee hives are trucked around
the country which gives them the opportunity to pick up diseases from one
state and then to carry it to another state in a matter of weeks.

It's also true that argiculture has been growing for millennia and
continues to grow. Populations work by how-many more than by
any-at-all. If honey bees were invasive compared to bumble bees they
would have started driving them out early on. If honey bees compete on
a near even basis then the steady increase of agricultural use would be
a deciding factor.

I suspect both are true. Bumble bees are suseptible to whatever causes
colony collapse disorder and ferral honey bees have gradually pushed
down the polulation of bumble bees without driving them rapidly towards
extinction.