Do wild colonies swarm themselves to death?

[Do224]

If bees have a perfectly good home, whether that be in a tree or similar, or in a purpose built hive….will they really swarm themselves to death?

I.e. when bees find a new home will they just build up in numbers until they have the urge to swarm…and then keep sending out casts until the original colony is unviable? Or will they usually stop swarming in time to leave a viable colony in the original nest…

Seems odd if they end up destroying the original colony by depleting it to the point where it can’t survive the next winter…especially if the nest is in a really good location

 

[Wilco]

Not really. I'd recommend having a bit of a read up on the topic but here are the basics (slightly oversimplified):

Bees are a superorganism. It's not about the survival of the individual but the colony's genes (linked to their relatedness). This is done via both drones and queens.

If a colony only maintains itself (single replacement via supercedure when queen gets old), ultimately bees would die out completely as freak events or failed matings would gradually kill off colonies (and there would only have ever been one colony!).

So it makes sense for bees to try to make multiple colonies to offset this and instead increase colony numbers. This is done by swarming.

The aim is to produce more viable colonies than they started with. This requires the bees to be in a good position to start with- decent colony size with stores. Thus cues for swarming are often linked to a when there's a crowded brood area, which commonly occurs when there's a lot of forage- typically late spring.

Workers will produce queen cells and once they are capped, the old queen (ready to lay) goes off with a chunk of the workforce in hopefully good conditions, to start elsewhere (leaving some workers, a lot of sealed brood and the queen cells behind). This departing group is the 'original' colony.

The new queen cells hatch and the first out may kill off the others before mating and continuing the colony at the original site. However, the genetics have shifted so it's technically not the same colony even though its the same site. This hopefully means there are two colonies when there was one.

In some instances, not all the virgins get killed so caste swarms with an unmated queen will go out with some of the remnant of the workers but there should still be brood to emerge to support the new queen getting going. This has the potential to lead to more colonies but is not guaranteed. It may also weaken the colony at the original site but not the original colony. However, as they have a proven site with premade comb, hopefully some stores and the conditions that trigger swarming tend to be favourable forage and weather, they should have a fighting chance.

Swarm instinct is usually highest in late spring (as per the cues for it) so by mid summer most colonies will be getting ready for winter and the instinct dies down.

 

[Erichalfbee]

If bees have a perfectly good home, whether that be in a tree or similar, or in a purpose built hive….will they really swarm themselves to death?

I.e. when bees find a new home will they just build up in numbers until they have the urge to swarm…and then keep sending out casts until the original colony is unviable? Or will they usually stop swarming in time to leave a viable colony in the original nest…

Seems odd if they end up destroying the original colony by depleting it to the point where it can’t survive the next winter…especially if the nest is in a really good location

I have "wild" bees in a box in a tree at the bottom of the garden. last year they sent out a prime and only one cast. The remaining colony is active still on sunny days.

 

[Ian123]

If bees have a perfectly good home, whether that be in a tree or similar, or in a purpose built hive….will they really swarm themselves to death?

I.e. when bees find a new home will they just build up in numbers until they have the urge to swarm…and then keep sending out casts until the original colony is unviable? Or will they usually stop swarming in time to leave a viable colony in the original nest…

Seems odd if they end up destroying the original colony by depleting it to the point where it can’t survive the next winter…especially if the nest is in a really good location

As a rule colonies do not swarm themselves to death. Things can go wrong during this period though and with duff emerging virgins and failed flights/matings colonies can be lost.

 

[Sanntos]

If there are varroa present, the wild colony will perish in the first or at the latest second autumn or winter (except in Blenhem forest)

 

[pargyle]

If there are varroa present, the wild colony will perish in the first or at the latest second autumn or winter (except in Blenhem forest)

But there are (with one or two exceptions of isolated areas in the UK) varroa in every colony ... there are certainly some varroa in my untreated colonies ... but they don't all die out. Some will, some won't - some don't get the chance to prove they can survive and manage varroa. I am not suggesting (or wishing to raise the issue again) that the Blenheim bees are amazing survivors and varroa resistant but I think we are very quick to quote the percieved and perpetuated wisdom and oft said Finman mantra ... "If you don't treat for varroa your bees will die out in 2 years."

But will they ?

 

[Sanntos]

I think it's safe to say that Finman is right (in this case) Besides, if something nearly always happens, like 99% of times....that is what is important. If we talk about the exceptions, the beginner will think they are the exception.

 

[jenkinsbrynmair]

If we talk about the exceptions, the beginner will think they are the exception.

I've always been told that I am

 

[oliver90owner]

If there are varroa present, the wild colony will perish in the first or at the latest second autumn or winter (except in Blenhem forest)

Accepted by many, but not necessarily true.

 

[Gilberdyke John]

I've always been told that I am

I'm handsome, kind and reasonable. I know this because my mother told me so.

 

[Boston Bees]

If there are varroa present, the wild colony will perish in the first or at the latest second autumn or winter (except in Blenhem forest)

No, not necessarily. That's too black and white a statement. Have seen a colony in a tree last 3 or 4 seasons. Varroa will certainly have been present.

 

[Sanntos]

Have seen a colony in a tree last 3 or 4 seasons. Varroa will certainly have been present.

Most probably repopulated.

 

[Boston Bees]

Most probably repopulated.

Nope, I see them pretty much everyday

Don't get me wrong, I'm as far from a non-treater as it gets. But the idea that varroa kills all feral colonies within two years is clearly too purist and not correct. Four or five, maybe (though even then, I suspect the odd 0.1% of colonies sneak beyond that).

 

[jenkinsbrynmair]

If there are varroa present, the wild colony will perish in the first or at the latest second autumn or winter (except in Blenhem forest)

No, not necessarily. That's too black and white a statement. Have seen a colony in a tree last 3 or 4 seasons. Varroa will certainly have been present.

I've found around here that they last between 3 and 5 years, but of course, being totally unmanaged colonies there may have been other contributing factors to their demise.
There used to be a wild colony in the wall of the old Bethel I care for, my mother's cousin (a lifelong beekeeper) said they had been there for many years - he used to visit the chapel early every year to out flowers on his parents' grave at palm Sunday, way before there was a chance of swarms in our area. I had been watching them for over four years, then that crazy cold spring of 2013 (I think) I observed they were active late February, then the long cold snap arrived and I reckon they died of starvation, I knew that they were a bit low on stores going into winter as the season before had also been crap.

 

[Sanntos]

Of course it's possible that a swarm emanates from a colony almost without any varroa. And if no reinfestation maybe they will manage three or even four years, but I doubt it. Normally they will be weakened in the first year, and die in the second.

 

[Boston Bees]

Of course it's possible that a swarm emanates from a colony almost without any varroa. And if no reinfestation maybe they will manage three or even four years, but I doubt it. Normally they will be weakened in the first year, and die in the second.

OK I know that you have basically no evidence for this, but it's clearly a strongly held belief, so fair enough. We all have them.

 

[Sanntos]

OK I know that you have basically no evidence for this, but it's clearly a strongly held belief, so fair enough. We all have them.

You're kidding?

It's a strong held belief based on evidence. Lots of research and computer models. Not many mites are needed for a colony to succumb the first or second year

 

[jenkinsbrynmair]

if no reinfestation maybe they will manage three or even four years, but I doubt it.

You're kidding?

but you have just been told of instances where colonies from swarms have survived beyond four years which disproves your pet theory - are you saying we're lying?

 

[Erichalfbee]

The colony in my tree are now in their third year. I watch with interest.

 

[Sanntos]

- are you saying we're lying?

Of course not, there can be exceptions. But it is hard to follow a colony close, and to know what exactly happens with it. A swarm can fly away very quick without a first gather in a nearby tree, as they usually do. If they have varroa, they try to be outside when doing their last flight. So it's hard to know or see when a colony diminishes. And another small swarm can repopulate the cavity just as fast. No beekeeper can watch a tree three years in a row. One must have a cup of tea now or then.