A beekeeper’s worst nightmare is opening a hive that is full of dead bees. It is a heartbreaking frustration when you have put in all the time, effort, and financial investment, and despite your best efforts, your bees are dead.
The truth is this is not a novice beekeeper problem. Beekeepers who have been working with bees for decades also face this horror from time to time.
It is in fact a common enough occurrence that the phenomenon has been given an official name: Colony Collapse Disorder.
Much research has already gone into the study of Colony Collapse Disorder, and much is still ongoing to help us understand the causes so that we can prevent our bees from dying.
Unfortunately, to date, there has been no one cause identified. Instead, researchers have found that the phenomenon is caused by multiple issues occurring at the same time either suddenly or over a period of time.
This does not help us beekeepers much right now, but teaching newcomers and the next generation may help them create better environmental awareness and help decision-makers come up with better farming solutions and conservation efforts that will help bee colonies.
It is normal to lose 5 to 10% of the colony during winter as fewer eggs are laid in winter. During an extremely bad winter, you could lose 15 to 25% of the colony.
This is completely normal; it is nothing to worry about. Anything more than 25% is concerning, however, and should be addressed.
So, why do they die? What can we do to prevent losing our bees and having to start from scratch?
The reality of beekeeping is that there is a number of reasons for the loss of an entire colony. In this article, I will cover eight major contributing factors that lead to colonies dying, and what you can do about it.
Table of Contents
We know beyond a doubt that pesticides are the single biggest killer to bees individually and to whole colonies.
Bees are a critical part of the food chain. They need pollen and nectar to make honey for the colony. Therefore, they move from food source to food source. This often means vast farmlands, crops, and residential gardens.
Sadly, farmers and homeowners alike are using chemical pesticides to kill off bugs that would otherwise destroy their crops and or flowers.
As bees move from plant to plant to gather pollen and nectar, they are picking up pesticides on the hairs on their legs.
They then take the pesticide into the hive, contaminating the whole hive, and causing the pesticide to kill all the bees in the hive.
What to Do About Pesticides
Speak to your neighbors about the pesticides they use. Let them know that you have hives and that your bees are important to them as farmers as they are the leading pollinators. There are many natural pesticides that are as effective as chemical pesticides.
These are not harmful to bees. Your neighbors may be happy to switch if they know that you have bees that will pollinate their crops or gardens.
Some bee-friendly alternatives you could suggest are:
- Kaolin Clay
- Gibberellic Acid
- Corn Gluten
If you have an uncooperative neighbor, keep your bees on the furthest part of the property, away from that neighbor. Make sure they have a good food source close by so that they do not feel the need to explore.
Lobby for the preservation of natural green areas, preserve natural wild habitats, educate local farmers about healthy alternative pesticides and organic farming, and lobby to ban the deadliest pesticides to bees:
- Meti Acaricide/ Insecticide
- Paraquat – which is the most harmful pesticide to bees
2. Habitat Destruction
The second biggest cause of colony deaths is the destruction of the natural habitats of bees.
This includes the construction of buildings, redirection of waterways, lack of preservation, and upkeep of green zones, and conversion from rural fields and farms to urban environments.
Fire is a bee’s worst nightmare. If there is a fire the bees will swarm or die.
Your bees may come back after a fire once the plant life starts back up and water is restored, but it is always better to prevent fire from either killing your bees or causing them to swarm.
When keeping bees, beekeepers need to consider all aspects of their habitats, not just the hive.
What to Do About Habitat Destruction
Ensure that the area around the hive is clean, control bugs, ensure there is ample water and plant life to harvest pollen and nectar.
Do your best to keep your hives away from where construction is underway. Remember that bees communicate largely via vibration; the use of electric saws, drills, jackhammers, etc. can cause the bees to feel under threat.
It is better to move your hive away from a construction zone until construction is completes and then move them back. Many responsible farmers will be happy to house your bees while you have construction underway.
They are even affected by cell phone usage, remember that when you go to your hive, it is better to leave your phone in your car or keep it switched off while you work in your hive – definitely switch off the vibration!
Parasite infestations are a major cause of colony collapse. In addition to the obvious issue of the bees being weakened by the parasites, there is a much more serious threat they pose to bees. Parasites carry dangerous infections that spread and kill easily.
They also feed on the bee’s honey, depleting the bee’s food stores causing the bees to die from malnutrition. The list of offenders is long, but there are some that are more likely than others.
The most dangerous parasites for bees are:
Varroa mites attack worker and drone bees feeding off their hemolymph and the brood, they lay their eggs in the brood cells (preferring drone brood), and the young mites will then feed on the bee pupa and emerge as adults with the young bee when it emerges from its cell.
Varroa Destructor Mite
Varroa destructor mite – also known as vampire mites because they feed on the blood of bees; they are the most dangerous parasites for bees, they are smaller than other varroa mites, but they often lead to the death of the developing bee pupa
What to Do About Varroa Mites and Varroa Destructor Mite
There are four forms of treatment you can choose from: coumaphos, fluvalinate, and 2 thymol formulations. Follow the directions carefully and do not treat during nectar flow. Remove the strips after the recommended time.
Varroa mites develop resistance to medication easily. Leaving strips in the hive for too long will help the mites do this. For the same reason, you should rotate treatments so that each emerging generation is not born resistant.
You can also add a few drone frames to attract the mites away from the all-important worker broods. Before the new mites emerge from the brood, remove the frame and place it in a deep freeze for 24 to 36 hours to let the mites die.
You can also use a screened bottom as this has been proven to slow the reproduction rate of the mites.
Tracheal mites (Acarapis woodi)
Tracheal mites prefer adult bees, they are attracted to CO2 emissions and enter the bee’s tracheal system via spiracles located on the thorax.
They feed off the hemolymph, and plug the trachea with themselves and their eggs, eventually killing the bee because of the inefficient oxygen exchange; infested bees are often found crawling on the ground outside the hive or on blades of grass or the sides of the hive.
What to Do About Tracheal Mites
The most effective way of controlling tracheal mites is to use menthol in the hive. This can only be done if the temperature is above 60 degrees and not during nectar flow. The bees breathe in the vapor which helps them breathe and also desiccates the mites.
You can also use an oil extender patty. This is very easy to make using 2:1 parts sugar to vegetable shortening.
Mix well and sandwich the mixture in wax paper. Make the patty 4 inches wide, and cut the paper around the patty to ensure the bees have access to the patty.
Your bees will be drawn to the sugar and when they go for a drink of the sugar, they will naturally pick up the oil on their bodies.
The oil becomes a chemical cloak making it impossible for the mites to identify the bee as a potential host.
This method will not affect the honey at all and can therefore be used any time and for as long as needed. You can even keep patties coming, replacing old patties with new ones.
Nosema ceranae is caused by two species of microsporidian parasites; it causes difficulty digesting food and the infected bee cannot produce royal jelly which means they often have no involvement in the brood rearing and become foragers instead.
Queen bees can also become infected and as a result, she will stop laying eggs; the lifespan of all infected bees is dramatically reduced.
What to Do About It
When it comes to Nosema, the best defense is an offense. Maintain large colonies in winter in populous, well-ventilated hives to keep the hive dry inside. Your bees will need a good supply of honey and pollen in winter, so do not get greedy.
There is only one reliable treatment for Nosema in honeybees and that is antibiotic fumagillin. Spores can live more than a year in the combs if they are not properly disinfected by fumigation.
Personally, I say dump the infected frames, the risk of infecting a new colony or a new generation is just not worth it.
Less dangerous contributors to Colony Collapse include:
- Small hive beetle (Aethina umida)
- Bee louse (Braula coeca)
- Larval greater wax moth (Galleria mellonella)
All living beings require water. Bees need it to make honey.
What to Do About Drought
If there is not a natural water source, make sure that they always have access to clean water.
5. Nutrition Deficit
Bees eat honey. That is their sole source of food. If they do not have access to pollen, nectar, and water they cannot make honey.
Overharvesting of honey by beekeepers often results in the death of whole colonies in winter when there is not enough plant life for the bees to harvest pollen and nectar. This means they cannot make honey and starve to death because of the shortage of honey.
What to Do About It
Do not overharvest honey! If you are in America, you should harvest from July to mid-September (if you are not in America, harvest just before autumn).
Your bees will require 80 to 90 pounds of honey to survive winter. Make sure you leave at least this much honey for your bees.
6. Air Pollution
Sadly, pollution is a problem that all living beings struggle with. Even more tragic, there is very little we can do about pollution on our own.
What to Do About It
What you can do is join activist groups that bring the plight of the effect of pollution on bees and other animals to the attention of policy makers and local politicians.
Even I cringe at the possibility that my local politicians would listen to my complaints, but if enough people are up in arms, they may – just may – listen and think before they allow new industries licenses to build in the area.
Make an effort to reduce your own carbon footprint. Here are some tips:
- Insulate your home so that you do not need to use much energy to heat or cool your home
- Use renewable resources like solar or wind-generated electricity
- Use energy-efficient products and turn off electrical appliances at the wall when they are not in use
- Avoid using cars that rely on gas or diesel
- Use less water by using bathwater or greywater to water your garden
- What you eat is monitored by shops as they monitor what sells in their stores, this then impacts what they stock; eating less meat and foreign food will force stores to change their buying habits
- Avoid plastic
- Make your own compost
- Instead of using paper, switch to digital – we all have smartphones these days making it easy to keep a diary, make notes, send messages, and type documents without impacting the preservation of our trees
- Reduce, reuse, recycle
Plant plenty of trees, plants, flowers, and grass to purify the air.
Pathogens do not just come in chemical form as in pesticides or air pollution. Viruses, bacteria, fungus, and pests such as other insects or parasites are also effective pathogens.
The most dangerous pathogens to honeybees are:
- American Foulbrood – infects the midgut of the bee, and can kill the whole colony
- European Foulbrood – affects the brood leading to the death of the larvae, the hive will eventually die as there will be no bees to tend the brood cells
- Chalkbrood – mummifies the brood cells leaving the cells spongy and chalky
- Stonebrood – mummifies the brood cells but leave the cells solid
- Sacbrood – turns larvae from white to yellow and then dark brown; causes deformation on wings
- Deformed wing virus
- Black queen cell virus
- Acute bee paralysis virus
- Chronic bee paralysis virus
- Israel acute paralysis virus
- Slow bee paralysis virus
- Arkansas bee virus
- Macula-like virus
- Berkeley bee virus
- Lake Sinai virus 1 and 2
- Kashmir virus
- Nosema apis
- Nosema ceranae
- Ascosphaera apis
- Appelligus spp.
- Melissococcus plutonius
- Paenibacillus larvae
- Lotmaria passim
- Crithidia bombi
- Crithidia mellificae
- Varroa mites
- Tracheal mites
- Wax moths
- Small hive beetles
What to Do About Pathogens
Inspect your hive regularly and treat it as needed as soon as possible. Make sure that you remove ants and other insects immediately.
8. Global Warming
Global warming is visible in the changes to the climate and environment. Extreme cold, extreme heat, and a lack of plants to forage from all lead to either colony death or swarming.
Education about the impact of global warming is crucial to the survival of bees. We can no longer keep our blinders on and pretend global warming is a myth meant to scare or distract people from politician’s antics.
It is real!
I moved to our new home in South Africa 16 years ago. When we moved here the winter month’s temperatures averaged from 50 F to 68 F (10 to 20 Celsius), and summer averaged from 64 F to 86 F (18 – 30 Celsius).
We are in mid-winter right now; last week we were 1 F to 40 F (-17 to 4 Celsius), and this week we have had 64 F to 78 F (18 to 26 degrees Celsius). This past summer we were averaging maximum temperatures of 35 to 48 degrees Celsius.
Plants that should not grow here are flourishing while animals who have been raised in this area are dying because of changes to the climate and diet.
Nature is screaming for help and our bees are dying because of it.
It is time to acknowledge this issue and lobby and educate officials to force them to take steps to help restore environmental balance.
To protect your bees, you need to monitor them constantly, do hive inspections once or twice every month (when the temperature is above 60 degrees Fahrenheit), and treat them as necessary.
We have to address all these issues. There is no One Cause for bee colonies to die. They die from a combination of issues that are environmentally based.
Educate yourself, educate your kids, neighbors, and especially your local and national lawmakers.
Ensure access to water and plant life.
Above all else, play an active role to force government to preserve, conserve, protect, and improve natural environments, farming methods, food production, and urbanization.
Di-Anne Devenish Seebregts was raised in an environment where daily life consisted of hiking, environmental conservation, growing fruit and vegetables, and raising poultry for meat and eggs.
She combined her passion for the writing word with her love of the pride that comes with not relying on others. She raised three children (who are now adults) to value the environment, and understand the value of being self-sufficient.
Find out more about Di-Anne on our About Us page.