Winter brood rearing?

[Little John]

In this case I reckon (for what its worth which is not very much) that there are probably a number of factors that trigger brooding. Light; Temperature; Scent of flowers would be my suspects.

Don't knock it There could be many variables from which to choose. I often wonder about our friend the mole who lives in a world completely devoid of light, but who somehow gets to know about seasonal changes too.

LJ

 

[Little John]

But would add it is often difficult to not become so specialised if you really want to understand a particular problem in science. This is one reason why collaboration is so important rather than simply postulating I reckon this is not important etc.

Fully agree. One of the major problems when attempting to make an 'objective' observation (which lies at the very start of the classic scientific method), is that you can't make such an observation - no-one can. A quick play with a Necker Cube will quickly show you that.

Each of us sees what we have been taught to see. That's the problem. So yes - collaboration between those schooled in different fields would seem to be the best way around this difficulty. But - that would require considerable tolerance, and a dropping of the attitude of 'my approach is right, therefore your's must be wrong'.

LJ

 

[Finman]

Whether he has or not, good science begins with the making of careful observations with an open mind - something sadly lacking in some who have been schooled in but one branch of science, and view the world though the monochromatic perceptual filter that such a limited education engenders.

Science is but one way of looking at the natural world - and a very useful tool it is too - but other perspectives are equally valid and equally valuable.

LJ

Thanks.... I have got education in Helsinki University in biology researching.
6 years were just teached how to use other's knowledge before you try to invent your own wheel. That is why I understand English.

Yes, reasearching is easy if some one pays for that: a good fee, laboratory, international co-operation.

And in science it is not habit to start to research things which are allready revieled 50 years ago. You do not get scientific merit from that.


But after all: beekeeping is not so difficult that we need science to answers to every question. Very few of beekeepers mind to open google to search something answer.




.

 

[charlievictorbravo]

You haven't got a hope - you only get funding for really worthwhile studies like why do conrflakes go soggy when you cover them with milk, or the dynamics of when a dunked biscuit falls into your tea.

I think you're wrong there JMB. You get the money for soggy cornflakes and dunking biscuits research if you can relate it to global warming.

"How climate change has changed to characteristics of corn-based products" or "Investigation into how climate change influences cereal crops and changes the moisture absorption of baked farinaceous confectionary" would both be likely to get money for research. So the secret is to relate the key influences for brood rearing to something that's happening or might be happening due to climate change - funny how we don't call it global warming any more isn't it?

CVB

 

[Finman]

"Investigation into how climate change influences cereal crops and changes .....
CVB

It is allready known. Looks great! Douple in 30 years.

 

[Apple]

funny how we don't call it global warming any more isn't it?

Surely it was only the "media muffins" and not scientists who in their ignorance used "global warming"?

Ozone holes seem to have dropped over the horizon, replaced by greenhouse gasses perchance?



James

 

[oliver90owner]

I often wonder about our friend the mole who lives in a world completely devoid of light, but who somehow gets to know about seasonal changes too.

I don't. Molehills is/are the answer, for the observant.

 

[Apple]

It is allready known. Looks great! Douple in 30 years.

Bushels per Acre!

Can someone give me the conversion factor to Kg per hectare?

(and everyone knows the increased yield is due to the Aggrochemicals and herbi~ pesti cides being poured over the land!)




James

 

[farbee]

It is allready known. Looks great! Douple in 30 years.

This graph does not show effect of climate change. There are many possible reasons for increased crop yield over the last few decades. Cause and effect is not established.

 

[domino]

funny how we don't call it global warming any more isn't it?

Surely it was only the "media muffins" and not scientists who in their ignorance used "global warming"?

Ozone holes seem to have dropped over the horizon, replaced by greenhouse gasses perchance?



James

It was never called global warming by science, it was a media tag line.

 

[Finman]

Bushels per Acre!

Can someone give me the conversion factor to Kg per hectare?

http://www.indexmundi.com/agriculture/?commodity=corn&graph=yield

Corn seems to be 11 tons/ha in USA

 

[Erichalfbee]

I often wonder about our friend the mole who lives in a world completely devoid of light, but who somehow gets to know about seasonal changes too.

I don't. Molehills is/are the answer, for the observant.

Our fields are practically devoid of molehills from the beginning of November. In the last two weeks they have suddenly started popping up with increasing frequency. Messrs Mole must know something's up

 

[BeeJayBee]

Eva Crane, in The World History of Beekeeping and Honey Hunting 1999 says

This early start of brood rearing is triggered by the increasing photo- period (day length), and is a necessary part of the bees' survival strategy. ​

Is she not referring here to early spring ? As there is no increase in day-length in December, and precious little in January.

I'm also curious to know how a zeitgeber is sensed within the (perhaps) constant darkness of a hive. As not all hive entrances allow sunlight to enter the box.
And - even if bees are able to leave the hive and make clearance flights, a free-running zeitgeber needs to be entrained to sunset in order to sense any increase in day-length. But how many bees make their winter clearance flights at sunset ?

No, the complete paragraph in the Google book is, allowing for my typo errors:-

Brood rearing restarts in January, after the days begin to lengthen but well before temperatures are high enough for bees to fly. This early start of brood rearing is triggered by the increasing photo-period (day length), and is a necessary part of the bees' survival strategy. By March, sufficient brood is being reared to replace the old bees that have died, and subsequently the population increases again.​

The natural world knows how to regulate itself, knows how to match raising young with the seasonal food supply, and if any members of a species make a mistake they don't survive into the next season.

In our garden, for example, each year we have Blue Tits nesting. They prepare nests very early but only start incubating when they (instinctively?) know that the time delay between laying, incubating and hatching will match the emergence of the crop of caterpillars in oak trees. If they incubate too early their chicks starve, too late and the caterpillars are no more with a similar result. The same with Robins - some years they pair up in late January, some years not until towards the end of the February, but it's still the same time in advance of the food they need to raise their young. We don't know what signs they see - but they do.

We believe that our own ancestors could tell when the days began to lengthen - Stonehenge etc - so shouldn't bees, with their millions of years of successfully getting the timing right, link the start of brood production with increased day length without going outside to look at the sunrise?

We're still learning how bees see the world, how they use natural signals. One day we may know their secret, and will probably borrow it and may even mimic it for ourselves - it might even help with food production.

 

[user 6228]

No, the complete paragraph in the Google book is, allowing for my typo errors:-

Brood rearing restarts in January, after the days begin to lengthen but well before temperatures are high enough for bees to fly. This early start of brood rearing is triggered by the increasing photo-period (day length), and is a necessary part of the bees' survival strategy. By March, sufficient brood is being reared to replace the old bees that have died, and subsequently the population increases again.​

The natural world knows how to regulate itself, knows how to match raising young with the seasonal food supply, and if any members of a species make a mistake they don't survive into the next season.

In our garden, for example, each year we have Blue Tits nesting. They prepare nests very early but only start incubating when they (instinctively?) know that the time delay between laying, incubating and hatching will match the emergence of the crop of caterpillars in oak trees. If they incubate too early their chicks starve, too late and the caterpillars are no more with a similar result. The same with Robins - some years they pair up in late January, some years not until towards the end of the February, but it's still the same time in advance of the food they need to raise their young. We don't know what signs they see - but they do.

We believe that our own ancestors could tell when the days began to lengthen - Stonehenge etc - so shouldn't bees, with their millions of years of successfully getting the timing right, link the start of brood production with increased day length without going outside to look at the sunrise?

We're still learning how bees see the world, how they use natural signals. One day we may know their secret, and will probably borrow it and may even mimic it for ourselves - it might even help with food production.

you cant tell day length if you only come out at midday, at if most days appear to be very dark but you can tell if the sun is getting higher on the bright days. The differences in Sun Altitude is easier and more reliable for the bees. True photo periodism i think you will find is more common for events nearer the equinoxes rather than Solistices for rather obvious reasons,

 

[Finman]

you cant tell day length if you only come out at midday, at if most days appear to be very dark but you can tell if the sun is getting higher on the bright days. The differences in Sun Altitude is easier and more reliable for the bees. True photo periodism i think you will find is more common for events nearer the equinoxes rather than Solistices for rather obvious reasons,

But now derekm, you invent your own science. Photoperiodism is very well researched and I have never found "sun altitude" in that issue.
It is clearly day length: 10 hours, 12 hours ... when an animal or plant is closed into dark.

in Finland we have long days but allways sun is low compared to South Europe.
Then in February days are very short and sun shining angle is very low. However bees notice that spring is coming.

Photoperiodism does not need bright sun.

There are too plants varietes where photoperiodism is breeded away. Some ever bearing strawberries have these sort.

 

[oliver90owner]

Brooding may well be initited by day length (if it ceases at all during the quiesent months), but will only be of limited numbers until suitable conditions prevail. Think, here, of beeks that encourage spring brooding by supplying thin syrup early in the year. They need extra water and protein for brooding (beyond simply carbohydrate needed for winter thermal energy generation). If one realises there is plenty of stores still available, it is only water that is really needed, not nectar substitute, for them to get brooding more quickly.

I used to feed thin sytup to colonies, as promulgated by generations of beeks, but found that reducing the supply to virtually water was just as good as a stimulus. An entry feeder 'inside' the Dartington was used to good effect back then.

The big problem for the UK is that the weather is that less predictable than some places, so colonies that are brooding at a good rate can be devastated by a prolonged period of very cold weather if the bees are then confined to the hive. It is these periods when I have lost colonies to isolation starvation in the past, I believe.

 

[Finman]

I used to feed thin sytup to colonies, as promulgated by generations of beeks, but found that reducing the supply to virtually water was just as good as a stimulus. An entry feeder 'inside' the Dartington was used to good effect back then.

.

So the beeks believe. It succeeds if bees can forage pollen from willows etc. If spring weathers are good, bees make as much brood as without feeding. (Yes, I have done this 30 years)

Bees are mad to rear brood in spring. They do not need encouraging. What you can arrange is a warm box. But if it is lack of pollen, bees can only stop larva feeding and they eate part of larvae. That is why early brood cappings area is porous.

But lets look to opposite side or the year. Day lengt and power of sun shive is same 21.March as it is 21. September. Sun is then in Zenit. Inspiration of brood rearing is very different in colonies.

.

 

[Finman]

.
It is well known that Carniolan bee has early build up compared to Italian.

It really is, because Carniolan store pollen over winter, but Italian tends to eate all stores in autumn. When I started to feed pollen patty toCarniolan and Italian hives, their build up speed were very similar. Difference was that Carniolans started swarming couple of weeks earlier than Italians.

 

[Finman]

.
Winter brooding and water


When I started to feed my colonies with pollen patty 25 years ago, I learned at once that if I start feeding too early and the ground is covered with snow, colonies become sick and they got chalk brood.

When half of ground was seen, then it was able to start patty feeding. Bees got drinking water enough from soil. Bees cannot take water from snow.

Couple years ago at the last weeks of April snow covered tha yard 7 days. It was frost and no bees can come out. During that week every single larva was disappeared from hives. Bees did not tear capped brood out.

I have seen often that bees do not eate pollen patty before midday. When they get outside drinking water, eating starts again.

 

[user 6228]

But now derekm, you invent your own science. Photoperiodism is very well researched and I have never found "sun altitude" in that issue.
It is clearly day length: 10 hours, 12 hours ... when an animal or plant is closed into dark.

in Finland we have long days but allways sun is low compared to South Europe.
Then in February days are very short and sun shining angle is very low. However bees notice that spring is coming.

Photoperiodism does not need bright sun.

There are too plants varietes where photoperiodism is breeded away. Some ever bearing strawberries have these sort.

For photoperiodism
There are two thresholds light level and time difference that the organism has to detect.
This is often done by a chemical reaction integration of the light levels and time.
This works well when the light levels and time period change fast and can give reasonable accuracy. But if your organism needs to accurately time close to the solstice there are problems.
The basic unrise sunset period changes are very very small, then the problem is detecting sunrise or sunset .Particulary at the winter solstice in maritime regions, the light levels vary enormously due to weather and the sun is rarewly observable at both sunrise and sunset. Thus at the winter solstice in maritime regions the organisms are required to detect very small signals inside overwhelming noise.
Basically organisms cant measure what is not measurable, or react to the undetectable.

They have to rely on other mechanisms to improve accuracy e.g. count days/time after an event closer to an equinox.

And experiments have shown that honeybees who kickoff their year close to the solstice are only very weakly photoperiodic when brooding. (i'll dig out the reference)