Extreme weather changes in spring and possible solutions
What you will learn here
- What to do with beehives (bumblebees) during spring weather changes
- Let's review how thermal insulation works
- How to decide – leave the hives outside or bring them indoors?
- What about the hives then and when to put them back?
- What about the hives where the mother has settled – should I feed or not feed them and how?
- When to feed and how to do it
- What to do if you can't move your hive indoors in the cold
CONTENTS
Introduction
How is the thermal insulation of the hive?
How long does it take for
the hive to cool down? After all, bumblebee queens can warm their brood.
How can a beekeeper prepare for such a situation and how should they react?
When to start placing queens in hives?
What if you have already started placing queens
? 1. If your hives are demonstrably empty, or you have not even tried to settle them?
2. If a queen has settled in your hive and is building a nest?
3. If you have tried to introduce a queen into the hive?
When to return the hive with bumblebees outside
? What and how to feed the bumblebees in an emergency?
When to give the queen mother a supplemental food?
How to supplement the bumblebees with a supplemental food?
How to return the hive with bumblebees outside?
Do not disturb the hive unnecessarily?
The queen has left the hive and has not returned to it?
Conclusion
A sleigh ride in a snowy garden
Photo PG Gröbl (21/3/2020)
Introduction
Spring often brings changes in the weather , and sometimes these changes are truly extreme. It often gets cold and sometimes it snows and freezes.
The situation is gradually worsening and the weather is changing rapidly due to climate change, with weather fluctuations becoming worse year by year.
Early bumblebee species are taking the risk of a drop in temperatures and are also taking into account the fact that it may threaten their nests, which they built early in the spring. But it gives them a certain competitive advantage: if they manage to take the risk, they are on the food supply in time and do not have as much competition. It is simply their strategy.
Bumblebees that nest in the ground (such as ground bumblebees – Bombus terrestris) take advantage of the fact that the ground has good storage properties . It heats up slowly, but also cools down slowly. Temperature fluctuations therefore do not pose much of a threat to the nest and the temperature in the ground does not drop in the spring. The rotting of plant material also has a certain influence on the temperature in the ground cavity, which adds a certain degree of temperature to the cavity.
When bumblebees settle in a hive (bumblebee colony), the situation is different . The hive will certainly provide them with a more pleasant environment for nesting than the cold ground in spring. However, if spring frosts strike, the hive will cool down and the nest in it is at risk.
Extreme temperature drops in spring
What about the thermal insulation of the hive?
We always recommend that the hive be built from quality material , for example from laminated wood with a wall thickness of at least 20 mm or more. However, the wooden structure alone is not enough , so we recommend that it be equipped with additional thermal insulation . This can be created by lining the inside/outside of the hive with polystyrene boards or by solving the insulation as an external one, for example with double walls. Air insulation seems to be the best solution.
External insulation is more effective, but not very practical or durable.
However, it is important to remember that thermal insulation alone will not warm the shelter , just like your house. Thermal insulation only slows down the temperature change . Therefore, if the shelter is not equipped with active temperature control, after a while its internal temperature will equalize with the ambient temperature .
A hive with good thermal insulation cools/warms up more slowly , a hive without thermal insulation cools/warms up more quickly. The mass of the hive (construction and internal volume) also has an influence on temperature changes. Even if you put 10 cm of polystyrene around the hive or wrap it in straw, the temperatures will still equalize after some time.
Small hives are the worst . They cool down/heat up first – they have a small volume of their own mass, a small internal volume and little lining. In addition to the fact that the nests of most common bumblebee species cannot fit in them, their thermal properties are unsuitable .
Therefore, we do not recommend using small hives and fortunately they are not sold much anymore.
Small bumblebee - unsuitable type
Photo from the manufacturer's website
Small bumblebee - unsuitable type
Photo from the manufacturer's website
How long will it take for the cold to subside?
This question cannot be answered simply because it depends on many parameters, mainly on the properties of the hive, especially its mass and thermal insulation.
In very simple terms, even high-quality thermally insulated hives will equalize their internal temperature with the surrounding environment in, say, 6-8 hours , as simple measurements show. So if you take them outside from a temperature of 20C, by this time the inside will have the temperature of the exterior.
So if you place a beehive outside, it will be able to protect the nest inside for some time thanks to the heat accumulation in its mass and thermal insulation. So if you don't want the nest to freeze, you can follow this rule as a guideline .
But after all, bumblebee queen mothers can warm their offspring
Mother bumblebees can warm their offspring with their bare bellies (see HERE ). But it has its limits.
The mother establishes the first generation of offspring in a small nest chamber . Only she and the case with the first eggs and then the brood can fit there. Here she can create a temperature of 30°C. Although the hive is equipped with good lining, it cannot heat the chamber for a long time and under all circumstances . If the temperature in the hive is below freezing repeatedly, the mother usually survives, but the brood gets cold. If the brood gets cold, its development stops and it dies. The mother is not always able to lay more eggs and often abandons such a nest and does not lay another one - it becomes a so-called "bludička".
The limit is also the lack of food , which can occur in prolonged cooling. Although the mother creates a wax cup for nectar in the nest chamber (see photo), it is not bottomless. If there is a lack of food in the area, she will not have nectar , which she needs as a source of energy to heat the fetus and as her food . She can manage without pollen for some time, but not without nectar. Among other things, this is why the mother does not have pollen reserves at the beginning of the nest, but nectar.
If the mother is alone (solitary phase), the nest cannot keep warm for a long time. Therefore, a long-term drop in temperature is a serious threat to the offspring. Once there are workers in the nest, the food supply is smoother and the nest also creates larger reserves of nectar/honey to bridge the gap. Some species store pollen reserves in empty cocoons (pollen-storers). A typical example is the early bumblebee species, the ground bumblebee (Bombus terrestris).
Fortunately, early species are just looking around for a nesting site in early spring and in most cases the mothers have not yet started building their nest.
Mother meadow bumblebee (Bombus_pratorum) with a large wax cup for nectar (light structure on the left) and the first cocoons (right).
The mother died after poisoning or after an attack by another bumblebee.
Photo O. Hercog (12/2/2019)
How can a breeder prepare for such a situation and how should he react?
The key to success is preparing your hive before the season . If you have a quality hive with good thermal insulation, short-term temperature changes will be able to withstand it for some time.
However, if the temperature drops, then even thermal insulation will not protect the hive and the breeder must deal with it.
If the hive is positioned and secured so that it can be easily transported , it can be brought indoors.
We won't force you to do this, the scar can be covered and insulated from the outside , but these solutions don't work very well.
We definitely recommend providing the mother bee with a sugar solution (syrup) in the hive.
As always, there is no black and white here. If the mother is strong, healthy and very active (biologically) , she can handle even greater temperature drops than we have listed here.
If the mother is caught in the cold right after she has moved into the hive and does not yet have her brood in it, she will simply stop nesting . She will seemingly abandon the hive and spend the night in nature. She will only visit the hive occasionally and if she does return, it will only be after the weather warms up .
So here too, the behavioral patterns of living creatures are much more complex and we as breeders can only wait and give them conditions that they will use when they want.
In the following text we will describe the strategies that can be used.
When to start placing queen bees in hives
Queen bumblebee mothers usually know that something is not to their liking and so they do not want to settle in. This may be the reason why you may not be able to settle in early spring, or why queens do not return to the hive immediately after a demonstration orientation flight.
If the mothers have just woken up from hibernation and haven't really started searching yet, they're more likely to just look around. Moreover, they probably feel that their time is coming and they'll return to the interesting place later.
Recommendation:
- Do not place queens in hives right away in the spring and rather wait for a truly long-term warming.
- Thanks to the cooling, the mothers will not start building a nest anyway, if they settled down and started laying eggs (sometimes after 3 days of permanent settlement), this could be a problem and would need to be addressed
- We understand that this can be hard to bear. By monitoring the weather forecast , you can adjust your settling strategy accordingly.
- If the weather forecast says that there are night frosts ahead and you don't have the opportunity to clean the house for the night, it's better not to put .
If you have already started settling the mothers
If you managed to settle the queen mother and she settled in there, congratulations!
But if it gets cold and nighttime temperatures drop, it's a problem and it needs your help.
When temperatures drop below 5°C and there is continuous snow cover in nature, action is needed.
1. If your hives are demonstrably empty, or you haven't even tried to populate them
Procedure:
- Keep the house dry (hallway/porch, etc.) so that it doesn't get wet unnecessarily.
- The dough doesn't have to be at room temperature, but it doesn't have to be frozen unnecessarily either
- return the hive outside when it warms up and the bumblebee queens start looking for nesting sites
- Remember that if you want to place the queen bee in the hive, it should not be cold and damp. Its temperature should ideally be the same as the ambient temperature.
Recommendation
- We highly recommend opening the hive and carefully checking to see if it is truly empty. Sometimes the queen bee may settle in the hive herself.
Risk:
- If the mother is hidden in the hive, she will climb out of the hive, you will then find her inside and release her outside to freedom
Hives (bumblebees) ready for settlement
Photo O. Hercog (18/3/2020)
2. If the mother has settled in your hive and is building a nest
If the mother has settled in, she flies to the hive, sometimes with pollen threads on her back pair of legs.
You can identify the movement by observation or using the marker , see HERE
Procedure:
- After dark, close the entrance hole of the hive, preferably with a ground cork plug, which holds well in the entrance hole (closing the flap is not enough, light will shine through and the mother bee would open it)
- Carefully transfer the bag to the interior.
- Only store the hive in a hallway/porch where it does not freeze and keep the hive closed (roof)
Keep the hive closed (inlet and roof) - If the scare is in the dark, the ventilation hole can be opened
- If you have made a protective net and have it installed as recommended, you can remove the roof from the hive in the dark, cover the net with a cloth and let it dry.
- If it is in the light , it is necessary to leave the ventilation hole closed . In the light, the queen would try to leave the hive through the open ventilation hole and would exhaust herself with useless attempts to escape.
- Leave the baby at home only for as long as necessary and provide the mother with food - see the next text.
Notice
- If you clean up the mess before dark, the mother may be on her way.
- Do not store the baby with the mother at room temperature, as this could cause heat shock to the mother – if you do, just gradually increase the temperature.
- If you place a cold shower in a warm room, water may condense on its walls.
- The same applies to returning the hive to the exterior
Risk:
- If the mother had built a nest and it was freezing outside, the nest would be lost
- Moving an occupied hive is also a risk, but if you are careful about jolts and don't tip the hive over, it can be managed
Protective netting placed on the hive.
Photo O. Hercog (2019)
Mother bumblebee (Bombus terrestris) on a protective flap
Mother's name Bobina
Photo B. Klimešová (2019)
Garden bumblebee worker (Bombus hortorum) at the entrance hole of the hive
Photo O. Hercog
(2/6/2019)
3. If you tried to introduce a queen into the hive
tried to introduce the queen into the hive , but you are not sure whether the queen will return to the hive (see using the marker), follow point 2 as if the hive was occupied = move the hive indoors closed.
If there is no continuous snow cover outside and the maximum daily temperatures rise to 2-5 °C, return the nest outside during the day. It is quite possible that if the mother nest likes the nest, she may return to it and check that this place will be available for settlement after the weather warms up.
Mother meadow bumblebee (Bombus pratorum) in a nesting box
Photo O. Hercog (20/3/2020)
When to put the bumblebee hive back outside
that keeping the hive indoors isn't optimal for bumblebees . But it's an attempt to keep them alive in extreme cold. Leaving them outside in the cold will do them no good.
always feeding the bumblebees in the hive during cooling periods or when cleaning the interior of the hive
Because it depends on many conditions, it is not possible to determine exactly when the bumblebees should be returned outside and when not.
Try to stick to the following guidelines and adapt your strategy to your capabilities.
- Leave bumblebees at home only for as long as absolutely necessary.
- There's no point in bringing bumblebees back out when it's freezing and there's snow outside.
- Once the morning/afternoon warms up and the predicted maximum temperature approaches at least 2-5°C , bring them back outside.
- If it is clear outside and the sun is shining, bumblebees warm up, making them more active and able to tolerate lower temperatures.
- The temperatures are more of an indication. A lot depends on the state of the queen:
a) If she has built a nest, then she can be active even at 2 °C, especially if she has brood and needs to find pollen.
b) If the queen has not yet built a nest, she will either wait in the hive and feed on sugar solution. But she will probably fly out and sometimes not return to the hive. Nature does not force her to take care of the brood, so she will prefer to move outside - However, you should expect that the nest will equalize its temperature with the surrounding environment within about 6 hours . It is not good to let the nest cool below 5 °C
Therefore, we recommend not letting the nest out right away in the morning, but waiting until the temperature rises a little so that it does not get completely cold . - If the queen returns to the hive and spends the night there, she will be home by nightfall . If the temperature is again below 5°C at night, it is a good idea to close the hive after dark for the night, place it indoors and repeat the process .
- We recommend giving the mother a complementary food - she can decide for herself whether she will fly or not.
- This situation in spring only lasts a few days = hang in there
- If you have settled the mother before the cold days, she will most likely leave the nest – she has no reason to stay there without her offspring. However, she may return to it after the weather warms up.
It is up to each breeder to decide and what strategy to choose , because there are many approaches and there is no single model and algorithm to describe it.
What and how to feed bumblebees in an emergency
If it is cold and there is a lack of food in nature, it is advisable to feed the queen bee in the hive with a sugar solution .
Bumblebees can survive for a few days on a sugar solution instead of the nectar they need for fuel . They also need pollen, but unless you have fresh pollen from a beekeeper, there's nothing you can do.
If you don't have fructose (Fructopur) at home, use sucrose (white beet sugar).
Mix sugar in warm water in a 1:1 ratio to form a solution (syrup).
Notice:
- Do not use brown (cane) sugar , as it can cause digestive problems for bumblebees.
- also do not recommend feeding diluted honey , as it may contain germs of bee diseases (even beekeepers do not feed their honey to bees).
- We have described the feeding and preparation process of sugar solution (syrup) HERE
For feeding, you can use a small feeder and place it on top of the lining, where the mother will find it herself.
The feed does not spoil in the cold, so it is possible to give it in a slightly larger dose, optimally in a tube feeder .
We described the feeders HERE
If you have your own frozen bee pollen collected on the hive's roof, you can put it on the lid of a PET bottle and put it on top of the lining. However, we would recommend waiting until then, it is not necessary.
You can buy pollen from beekeepers, but they will only be for last year's bees.
There is a possibility of transmitting bee diseases to bumblebees, so using bee pollen as a side dish
Wort for bumblebee food – Fruktopur
Foto Internet
Bumblebees PLUS – Test tube feeder – inclined position
Photo O. Hercog
Feeder made from a PET bottle cap with a cotton insert
L
Pollen grains in a PET bottle cap
When to give solid foods to the mother
In general, we do not recommend feeding bumblebees. The exception is when temperatures drop and there is a lack of food. In that case, it is appropriate to give the mother a supplement. The mother decides for herself whether to use it or whether to fly out for fresh food. Practice shows that mothers prefer to fly out if the temperature is not below zero. Hardy alpine species of bumblebees even fly in temperatures well below zero; they expect such conditions and find a source of food in the local nature.
We recommend feeding in the cold.
If you have a hive outside, it is not a good idea to open it outside so that it does not get even colder. So it is better to close it and bring it indoors and leave it alone. Then you can feed the mother , for example at night.
But if the scare is outside for a long time, it basically doesn't matter , the temperatures will be practically identical. It depends on your judgment and the situation.
If the hive was/is outside, the mother will probably be frozen inside and will not fly out. Place the feeder on the lining and close the hive with the roof. The mother will gradually warm up and find food .
Notice:
- Don't disturb your mother unnecessarily
- Do not look into her hive other than when you are feeding her.
- do not try to find its nest chamber – it is fragile and can easily be irreparably damaged
Test tube feeder - vertical position
The mother will find the feeder more easily, but then it is better to remove the feeder and cover the bottom with a lining so that the bumblebees do not poop there (illustrative photo)
Photo A. Votavová
How to supplement bumblebee food
If you supplement the feed and the mother is active in heat, she may have a tendency to fly out of the hive.
Procedure:
- We recommend supplementing feeding in the dark (for example, in a closed bathroom) and using red light (headlamp, bicycle lamp, foil on a flashlight), because the mother will not fly out in red light.
- Turn off and turn on the red light.
- Carefully remove the hive roof.
- If the queen climbs out of the hive, carefully catch her and return her to the hive – preferably with a beekeeping trap
- Place the feeder on the lining and close the roof.
- If you're worried your mother will leave in shock, do it in the bathtub
Note:
- Sometimes it is recommended to feed the bees at the entrance of the entrance tube in the hive. This makes sense, the queen finds it more easily. However, it means that there is no lining at the entrance of the tube
- We consider it a better solution to have the entire hive filled with padding so that the bumblebees do not poop on the bottom and spread it around the nest.
- We also consider it a better solution when there is a compact mass of lining in the hive, which thus creates better thermal insulation of the nest cavity created in it
How to get a bumblebee hive back out
As we wrote, moving the hive indoors is an extreme emergency solution. Therefore, we recommend returning it as soon as possible.
We have described guidelines for when to bring the scare back out HERE .
Procedure:
- Place a dose of sugar solution into the hive (see procedure above)
- Carefully transfer the hive to its original location and remove the inlet cap
- The mother will fly out after a while, probably doing a short orientation flight (surprised that she didn't get out as she wanted), then she should normally continue nesting and flying depending on the outside temperature
- If you put sugar solution in the feeder in her hive, she will decide whether or not to fly out
- But keep an eye on the temperature and don't let the jar cool down unnecessarily below 5 °C.
- Keep in mind that the temperature of the hive will equalize with the surroundings within 6-8 hours and plan accordingly when returning the hive outside.
Additional external insulation of the hive
You can try to insulate the occupied hive with additional external insulation.
As we wrote, this is not a full-fledged solution and a replacement for heating . It will only give the hive a better chance and slow down the cooling.
Procedure:
- Cover the outside of the hive with boards, additional polystyrene insulation, or other insulating material such as hay, straw, blankets, etc.
- this insulation with a waterproof foil (plastic sheet, etc.) and secure it with stones to prevent it from flying away.
- However, the insulation should be done in such a way that the view of the hive from the flap side does not change. Unfortunately, this will not insulate the front wall. If you change the view of the hive, the mother bumblebee may no longer be able to find it.
- If you decide to take the risk and insulate the front side, do it at night so that the queen can make an orientation flight after leaving the hive and remember the new appearance.
- You can help this by forcing the mother to take an orientation flight – just leave the entrance closed after dawn. Once the mother flies out, she should react to the closure and make another short orientation flight to find out what happened. This should help her remember the new situation.
Please consider this as a last resort in case you have no other solution.
Emergency covering of a bumblebee hive with additional thermal insulation
Foro M. Bradová (21/3/2020)
Do not disturb unnecessarily
We kindly ask all curious beekeepers, except for transfer and feeding situations, not to disturb the mother in the hive .
All the actions described above disturb her to the very limit of tolerance. Any further checks and unnecessary looking into the hive are unnecessary and may be the last straw for the queen to fly away.
We know cases where such unnecessary looking has done exactly this...
The mother left the nest and did not return
The chances of a mother overcoming such a crisis depend on many factors. Sometimes it happens that she leaves the fear and does not return to it .
In such a case, we recommend leaving the hive with the flap open and closing it outside at night and cleaning the interior as if it were dark.
When it gets warmer and the temperature drops are gone, leave the scarecrow outside and place a marker in the air inlet .
Wait at least 3 days before trying to replace the hive with a new mother. There is a chance that "your" mother will return and hope dies last, or at least during those 3 days.
Conclusion
- We understand that moving the hive indoors is not an optimal option and has its risks .
- If you don't want to do that, at least solve it with additional thermal insulation of the hive .
- But if you don't address , the nest's fate is sealed.
- The entire solitary phase of the mother is very critical and the mother will easily leave the nest . Therefore, if you undertake the above work, try to be as careful as possible and, apart from transferring the hive and feeding, do not disturb the mother, for example by observing her further.
- The mark must be enough for you, do not enter the hive . If you disturb the mother unnecessarily, it may be the last straw in her patience. Therefore, do not disturb the mother and do not even try to find her nesting chamber.
- After warming up, wait and give the mother a chance to return . Even if she leaves the nest, she may return. Give her 2-3 days after warming up .
- If you do lose the queen and do not have a hive equipped with internal insulation (interior space and roof), add insulation and only then continue settling . Cold weather can come even in May!
It is up to each breeder to decide and what strategy to choose, because there are many approaches and there is no single model and algorithm to describe it.
We keep our fingers crossed that your queen bees will survive the warming weather in their hives, that their families will grow successfully, and that their daughters will live to see better times.
So you see, breeding bumblebees is a joy, but sometimes also adrenaline and nerves. However, if you have decided to breed them, you have also accepted a certain responsibility and it is right to take care of them. After all, it is the same as with other pets, where you also do it and enjoy it. Fortunately, we do not have to vaccinate bumblebees and take them to the vet for check-ups.