Pests and Disease
This site will give a brief summary and images of the pests and diseases to look out for. Click on the links above for a summary of the information you require.
This link provides a list of notifiable diseases and the contact names and numbers to notify the department of primary industry. List and contacts for notifiable diseases.
Some diseases require irradiation of equipment, and the beekeeper can request compensation.
The DPI sites in all states have very detailed information. The following link to the DPI in NSW has a series of 9 videos on Pests and Diseases as well as hard copy resources that will give you detailed information.
The Seasonal Tasks Link on the left includes hive management procedures to carry out. Good Hive Management practices go a long way towards reducing and controlling pests and diseases in your hives.
Attending Field Days gives you the opportunity to listen to talks given by experienced beekeepers. This provides you with the opportunity to ask questions for your own needs. You can purchase various hive components, and get to know others with the same interest as you.
Marong Field Day all crowding around a demonstration.
Small Hive Beetle (SHB)
This beetle is attracted to the pheromones sent out from a weak, diseased or queenless hive. Keep your hives from being stressed. Stressed hives attract beetles. Strong hives can deal with the beetle. The DPI have a video on the Small Hive Beetle at: Small Hive Beetle Video it is 7.09 minutes long.
The following information and more can be found at the RIRDC site at:
Freezing frames kills both larvae and adults.
Queenlessness will attract beetles, and the presence of a small amount of brood and also pollen encourage beetles to reproduce. Unite colonies if necessary.
Above 2 images courtesy of the DPI.
Above image courtesy of RIRDC slimed frames
Best Management Practice
1. Keep all hives strong. Don’t try to keep weak hives going.
Use beetle traps to reduce numbers to keep them under control.
Ants are more of a nuisance than anything, so place your beehive away from any known ants nests, or get rid of the ants nest. If you have a problem then stand each leg/brick that holds the hive above the ground into a can of oil or water so that the ants can't climb into the hive. Another way that I haven't tried myself is to sprinkle cinnamon around the hive and under the lid. Apparently Ants hate it, and its not harmful to bees. each time it rains you would need to re sprinkle.
Heavy crop yields and summer rains have created ideal breeding conditions for mice, with areas of New South Wales, South Australia and Queensland inundated with rodents, the Geelong Advertiser said.
The Department of Primary Industries have reported outbreaks along the Murray River.
Mice can come in their hundreds and when this happens mouse guards can be fixed to the beehive entrances. These allow bees to come and go but not the mice. If a harvest is happening near your hives, then fix the mouse guards to the entrance before the harvest has started.
Mice can also destroy a healthy hive during the winter by eating through the comb and eating bees and honey. Fixing mouse guards to your hives for the winter period can also close part of the entrance as well as keeping the mice out. You can purchase various styles of mouse guards, some are made from metal, as in the image.
Wax Moth - By Doug Somerville - Full article can be found at: Wax Moth DPI
The greater wax moth (Galleria mellonella) and lesser wax moth (Achroia grisella) are major pests of stored or unattended combs. The greater wax moth causes the most damage; however, the lesser wax moth is generally more common, and can also cause significant damage. The two species tend to coexist, and are frequently found in the same location.
The primary concern for beekeepers is how to adequately store combs without them being destroyed or damaged by the larval stages of the moths. Destruction or damage to combs can also occur within weak hives which have died or have low populations. The presence of an adequate number of adult bees will prevent wax moth damage. It can be assumed that wax moth will never be completely eliminated from an apiary or storage shed.
Control of Wax Moth - Freezing
All life-cycle stages of the wax moth, including eggs, are killed by freezing at the following temperatures and times:
- - 6.7C at 4.5 hours
- -12.2C at 3 hours
- -15.0C at 2 hours.
It is important to commence timing of this treatment only when the hive material or apiary products have reached the recommended temperature. A number of hobby beekeepers have purchased small freezers and find freezing an excellent means of protecting their combs.
After freezing, the combs should be stored in a moth-proof environment to prevent re-infestation. Sealed, strong plastic garbage bags provide a good insect-proof storage environment.
Combs that have been frozen and then placed in untreated supers for storage are immediately at risk to infestation because the supers may contain wax moth eggs. It is best to treat the super and combs and then place them together in a sealed plastic bag.
Provide a light source
Wax moths hate the light. So supers can be stored on top of each other, with a light source at the base, shining up through the stack.
Sometimes these are confused, as you can see the wasp is slightly larger than the bee, and has yellow legs and bright yellow and black stripes on their back half with black dots between the stripes, down each side of the abdomen. They are very aggressive and kill honeybees and rob their hives.
The following information came from :http://www.pestcontrol.org.au/Bees-Wasps.html
European wasp and English wasp
The hymenopteran insects known as wasps can also pose quite a severe threat to the safety of humans and animals. Many species are capable of inflicting severe stings but two species which have gained prominence in some parts of Australia are the European wasp (Vespula germanica) and the English wasp (Vespula vulgaris). Both of these species have been introduced from overseas. The European wasp can now be found in Tasmania, Victoria, Sydney and some country areas of N.S.W. The English wasp can be found in Victoria.
The workers of both species are about the same size as bees but have conspicuous lemon-yellow banded markings on a black body. The colourless wings are folded longitudinally when at rest.
They construct rounded community nests, normally oval in shape, usually about 1 metre in length but, here in Australia, where colonies may live over winter, the nests may be 3 to 4 metres high and contain up to 100,000 individuals. They are predatory social insects and often act as scavengers in urban areas. They tend to nest around human habitation where there are greater opportunities for finding food. This food may include fruits, confectionery, cakes or soft drinks. European wasps also destroy honeybees. In spring and summer, the wasps are very aggressive and will swarm to attack anybody whom they consider a threat to the nest. The sting is more painful than that of a bee and each wasp may sting the victim many times. The wasp does not die after stinging.
This aggressive colonizer now threatens rural industries such as berry and grape growing and beekeeping and has the potential to impact adversely on tourism when they are very abundant at outdoor venues.
Seek pest control for wasps nests as they kill and rob honey bee hives.
The following information comes from the DPI Victoria and the full article can be found at:
Infection does not normally pass directly from infected bees to the next generation of adults. Instead, young bees become infected when they ingest spores as they clean contaminated combs.
During the summer months, most honey bee colonies carry a few infected bees with little or no apparent effect on the colony. Spores may also persist on the combs. As the weather in autumn changes, these spores may initiate an outbreak of nosema. Losses of bees at this time of the year may be very heavy.
Winter losses can also be heavy. Infected bees confined in their hives due to bad weather may defecate inside the hive soiling the combs and hive interior with excreta and spores. This, together with spores produced in the preceding autumn causes infection in spring.
Spring outbreaks usually begin in late August or September, when temperatures begin to rise. They may last until late spring or early summer.
When the warm weather comes, the disease begins to decline due to improved flight conditions. The source of infection is largely removed because the bees are able to defecate outside the hive thereby reducing the contamination of combs.
Fortunately, serious nosema outbreaks do not occur every year. Research has indicated that the following conditions appear to be associated with serious autumn outbreaks and epidemics of nosema:
- heavy summer rainfall
- an early autumn break in the fine weather about mid-March to early April
- bees working grey box (Eucalyptus microcarpa), red ironbark (E. sideroxylon) and white box (E. albens).
The exact reasons for these apparent relationships are not known. In these epidemics, strong colonies may be seriously weakened before winter. They may be reduced to the size of a nucleus colony in a matter of days. Infected colonies that survive the winter may require a long build-up period for the population of adult bees to reach normal numbers.
Losses caused by nosema disease are not confined to areas of Victoria having the field conditions mentioned above.
Spores of Nosema apis may occur in honey or pollen. Research reports indicate that honey bee workers can transmit nosema to queens in queen mailing cages, queen banks and queen mating nuclei.
American Foulbrood (AFB) This is a notifiable disease.
The DPI provide a honey culture testing service to see if your hives are carrying AFB disease. This will be sent to you when you register your hives, and you are advised to have this done on an annual basis.
A series of 9 videos explains and demonstrates diseases in bees. A video from this series (The DPI Govt of NSW) has provided the information for this article. For full information please go to the following site:
DPI American Foul Brood (http://www.dpi.nsw.gov.au/agriculture/livestock/honey-bees/pests-diseases/videos/video-7.)
When examining the brood box for AFB, look for concave brood cells that are discoloured (chocolate brown and sunken), a bit greasy, some with dead brood, and chewed cappings.
A rope test can be carried out in the early stages of the disease by inserting a match into a capped cell and drawing out a rope of slime. In advanced cases, the cells are full of scale when you look down at the cells from the top frame.
Advanced stage there is an odour coming from the frames.
Typical look of brood with AFB
Rope test carried out with a match
Management Strategy for AFB
- Inspect hives in spring, summer and autumn and look in the brood box for symptoms.
- bees may rob a weak hive either yours or somewhere else and then your bees will bring back the disease to your hive
- Don't move components from hive to hive unless you are sure none of your hives has a disease.
- Barrier system where the equipment for each apiary stays in that apiary
- Feeding back honey or pollen is high risk for spreading disease.
- Invariably its the strong hives that get AFB not the weaker ones.
- very small risk in introducing AFB by re queening
In the end the colony must be destroyed and the hive equipment will need irradiating to get rid of the spores that last for many many years. Unfortunately the bees will need to be killed otherwise they will spread the disease.
This is a notifiable disease. So call your local apiary inspector to see what to do next if you suspect you have it. Go to Laboratory Notes from DPI for details.
European Foul Brood (EFB)
Full article is at: EFB DPI NSW
EFB can cause extensive losses in both amateur and commercial apiaries. EFB is highly contagious with all stages of larvae development susceptible to infection. There are a number of symptoms that are similar to AFB, and these two brood diseases can be confused.
Incidences of the disease are strongly correlated with climatic and nutritional stress factors. Cooler wet weather, poor nutrition and moving bees can promote the incidence of this disease.
Figure 1. The bright white larvae are healthy. The larvae that have a yellow colouring are infected with EFB.
The uneven aged larvae in the comb also suggests that the colony may be diseased as the worker bees regularly remove diseased larvae.
Image courtesy DPI NSW.
Signs of the disease
- Brood affected with EFB may have a mottled, peppered appearance, with healthy brood cells intermingled with dead or dying ones.
- Larvae are mostly affected in the unsealed, curled up stage, although in severe cases brood of all ages may be affected.
- Their colour changes from pearly white to yellow and finally, yellowish brown. After two to four weeks, larvae dry up to form a brown scale which can easily be removed from the cell.
- In some cases sealed brood is affected and the capped brood takes on a mottled appearance with scattered sunken and perforated cappings. Pupae may have a similar appearance to those affected by American foulbrood.
- The odour of infected brood varies from odourless to sour or foul, depending on the secondary invading bacteria present.
- Outer combs of the brood nest may show signs of the disease earlier and may have a heavier infection than inner combs in the same colony.
- Dead brood probed with a matchstick usually has a watery consistency, although the sealed brown pupae may exhibit a slightly ropy consistency.
Worker bees may remove and discard diseased larvae as they die and thus a colony may show few signs of disease.
The only accurate diagnostic method is laboratory examination, particularly where the stages resemble signs of AFB. These are FREE.
- While there may be times when antibiotic treatment is the only answer, the practice is becoming increasingly less attractive because of the possibility of honey contamination and the development of resistant strains of EFB.
In some commercial operations antibiotics are not used at all. Consider the following forms of prevention – all factors combined will certainly reduce your dependence on antibiotics.
Re queen on a regular basis
A young vigorous queen will always do better than an older queen. Select disease-resistant breeding stock.
Maintain hive hygiene
Regular replacement of brood nest combs will help to reduce the concentration of disease-causing organisms in the brood nest. This can be done by placing two or more white combs or foundation in the brood nest each year.
Shift bees with care
Shifting bees has long been recognised as stressful to bees. Moving bees at night with an open entrance will minimise stress. Moving bees closed up may lead to excessive heat production and associated stress. Bees are more likely to show signs of EFB soon after being moved.
Chalkbrood is caused by the fungus Ascosphaera apis and it affects both sealed and unsealed brood. Full article can be obtained at the Qld DPI.
DPI Queensland Chalk Brood
Appearance of Chalk Brood
At first, larvae are covered with a fluffy white fungal (mycelial) growth that looks like white mould on bread or very fine cotton wool. Larvae become swollen inside the cell. Later, the dead larvae dry out to become hard, white or grey/black chalk-like mummies.
Chalk Brood Image courtesy DPI Qld.
Dead mummies outside hive entrance
Management practices that reduce the stress on hives also reduce the number of chalkbrood spores. Maintaining strong healthy colonies has been demonstrated to reduce the effects of chalkbrood.
Management practices which may reduce the effects of chalkbrood disease are:
Good hygiene will also help. Change clothes and disinfect smokers, boots and hive tools using chlorine bleach between apiaries or infected hives.
Spores remain viable for up to 15 years or more in equipment and soil. Use of contaminated sites and old equipment could lead to infections. Interchange of equipment by the beekeepers also spreads the disease.