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It's vital to know other beekeepers and grow the skill's bank for beekeeping in SA and the world!
We are so excited!
The Winter Solstice has come and gone in the Southern Hemisphere. It marks the shortest day of the year - as well as the middle of winter.
The opposite, of course, can be said for the northern hemisphere!
"Knowledge about various bee diseases, pests and parasites are an important aspect of beekeeping management."
Certain diseases and conditions have distinctive symptoms in contrast to viruses that do not produce distinctive signs in the field. Some of these diseases, pests and parasites can be avoided while others can be dealt with." ~ Notes from Dr Human.
What are the 3 most challenging pests for bees?
It's very much the case of our experience in South Africa that we can say with general accuracy that the three most challenging pests currently and overall are the small hive beetle, the wax moth and the ant!
There are minor pests or pests less effective on the overall performance of honeybees and these would be bee pirates, bee eaters and braula.
Let's talk about Diseases
Bacterial diseases:
American foulbrood (AFB)
Infection is caused by the spore-forming bacterium Paenibacillus larvae. This disease can result in sever colony losses. It affects only the brood, is highly contagious and extremely difficult to eradicate. The bacterial spores can remain viable for up to 60 years and are extremely resistant to heat extremes and chemicals.
Infected larvae die and a distinctive foul smell develops upon decomposition. At this stage the remains of the larvae can be drawn out as a string (extend up 10 -30mm). There after the remains dry out to dark and highly infectious foulbrood scales that remain in the cell. Infected colonies have scattered and uneven brood patterns with dark, greasy-looking, sunken cappings.
In South Africa, it is required that any colonies found with confirmed AFB infection should be destroyed by fire. Report the finding to the DAFF. The entire bee hive, frames and lid should be burned. The ashes to be buried. It is quite disheartening to say the least. But it is to preserve the remaining healthy colonies that such drastic steps are to be taken.
Experiment: There is a beekeeper testing a method which may permit at least the saving of the wooden hive and components despite having to destroy the colony itself. The method involves dipping the wooden components in a drum of paraffin wax at 160 degrees Celsius for 20 minutes. This has the potential to destroy the bacteria.
Additional methods of destroying AFB in the wooden components:
One can use irradiation by gamma rays to eradicate the bacteria however it comes at a cost. Packaging, delivery and preparation for the irradiation plant may outweigh the benefit of trying to reuse the hive components. There is one office in Isando, South Africa that MAY provide sterilisation in this way.
Caution: When dealing with infected colonies any equipment used that comes into contact with the bees, honey or comb may transfer the bacteria. Be very diligent in keeping your gloves and hive tool free of contaminated bacteria by washing them both with bleach in a shallow container nearby when working multiple hives in a single apiary and between apiary sites.
EXTREME CAUTION: There is a major risk of spreading AFB if honey is removed and extracted from infected hives. Although the AFB bacteria is not harmful to humans it can be spread by leaving spilled or unfinished honey in open containers that end up in dustbins or rubbish landfills.
Alternative resources on AFB:
What about European foulbrood (EFB)
This brood disease is caused by the non-spore forming bacterium Melissoscoccus pluton. It affects open brood and is common during spring when brood rearing is at its height. Colonies may be severely weakened. EFB is considered a less serious disese than AFB but high losses have been recorded. Infected larvae appear coiled/twiseted in their cells with a brownish colour and normally die when they are 4-5 days old. Sometimes one can detect a sour odour.
Source: P Kryger
Braula or bee louse usually confused with Varroa
A small louse or tick-like mite which Scutellata can usually manage themselves when cleaning each other. It is more round in shape than the Varroa.
 Scutellata worker bees with queen. Spot the braula (bee louse) on the worker bee next to the queen. (Source: P. Kruger)
Fungal diseases
Chalkbrood
This is a disease affecting sealed brood and is caused by the fungi Ascosphaera apis. The presence of chalkbrood is influenced by climactic factors, which influence the temperature and humidity in the hive, especially when it is cooler and wet. This fungus can affect a single colony or an entire apiary or even regions in "chalkbrood years". At first larvae are covered with a fluffy, whitish fungus growth. After death the larvae become mummified and have a chalk-like appearance; the colour varying from white, to grey to finally black.
Honeybee Pests:
Small hive beetle (SHB) – Aethina tumida
Small hives beetles are endemic to sub-Saharan Africa. African bees are able to keep the beetles in check but weakened colonies may lose control over their beetle populations. The colonies will then abscond and leave the infested nest site behind.
However, they have recently been introduced in Northern Africa, Italy, Australia, Hawaii and North America where it developed into a pest resulting in devastating infestations.Small hive beetles feed on bee brood and food reserves and reproduce within hives, but as soon as the larvae reach the wandering stage, they crawl out of the hives to pupate in the soil, (within 20m of the hive).
We sell small hive beetle traps from our shop in Centurion.
Wax moth – Galleria mellonella
Wax moths are known to cause serious damage in hives after the bees have been driven out or in comb stores. Burrowing larvae leave silk trails behind and can, in extreme cases, destroy the entire comb, with only a matted mass of silk and other debris remaining.
Moth's larvae destroy the comb and gnaw wooden material as they get ready for pupation. Their cocoons are very sturdy. Strong colonies are not susceptible to damage since they can control the population of moths. The wax moth is adapted to warm climates and generate less damage in cold regions or at higher altitude.
Management: Add entrance blockers to the front of the bee hive reducing the area bees would need to guard against form invading pests like wax moth, Capensis and large hive beetles. Simple to make, the hive entrance reducer or blocker is a wooden or plastic strip that fits across the entrance of the hive leaving two small blocks open allowing reduced access like a traffic control for a high way divergence.
Parasitic Mites:
Varroa destructor
These are external parasitic mites that feed off of the haemolymph (blood) of developing and adult bees. Examples of the damage caused by these mites are morphological deformation, reduced lifespan, weakening of the immune system and transmission of secondary diseases.
Varroa mites are one of the most serious pests of European bees worldwide and now also found in South Africa; if infested colonies are left untreated by the beekeeper, the mites will kill the colony within 2 to 3 years. The mites need brood to reproduce and they find drone cells more attractive to breed in than worker cells.
Within my experience, reports of South African colonies coping with Varroa are common as long as the colony is strong. The "African Killer bee" may well revitalise European strains in the Americas in the long term as long as chemicals are not used to "strengthen" the Varroa mite.
Some countries decided to use chemicals to treat Varroa. Since then Varroa has become resistant to these chemicals and therefore also harder for bees to adapt to as a pest in a natural way. South Africa has not followed in similar footsteps in general and rather looked for alternative methods of managing the Varroa mite.
One method of managing the Varroa mite is to insert a super frame into the brood chamber. This frame is usually drawn out with drone cells. As Varroa are drawn to drone cells for reproduction the Varroa gather on this frame. Once it is time for the drone cells to be sealed the entire frame should be removed and the comb can be removed entirely and then varroa destroyed.
CAUTION: There are products still being used in various countries that create stronger resistant strains of Varroa which there make it even harder for natural resilience of honeybees to adapt.
France has since banned these products and a number of manufacturers have also stopped producing their products due to the adverse affects on the medium to long term making Varroa more resistant.
Note to South African beekeepers:
There has been an unfortunate breach of the Capensis barrier between The North-South line between the two distinct subspecies of Apis Mellifera in South Africa. It took place as far back as the early 1990s already.
A beekeeper moved a few hundred bees across the natural barrier prescribed in the Blue Book and by the DAFF and SABIO which resulted in the introduction to the Capensis subspecies to the North into the Scutellata territory.
Since this disaster, thousands of colonies have been lost and or killed due to Capensis infestation in the north. Due to the fact the Capensis is not a natural honeybee above-the-line it is also treated as a threat to Scutellata colonies and falls into the pest category. If you find very dark or nearly black bees in your Scutellata colony, especially where multiple eggs are in cells, there is likely an infestation of Capensis.
Management: When inspecting your Scutellata hives check for multiple eggs in cells as well as any eggs in the super chamber if you are using a queen excluder. Unless you find the queen bee in the super chamber doing the royal business it is likely you have Capensis bees. Capensis workers can lay eggs like a queen which is not the case for any other mellifera subspecies.
These colonies should be destroyed. NOT THE BOXES! Confirm with a friendly beekeeper and or contact your local bee association if you are suspicious above-the-line.
Tip #2: As Capensis workers can move through queen excluders and begin laying eggs there which can eventually breed large numbers of workers it is advisable to use no more than 3 super chambers on top of each other in the Northern territory.
Historically, beekeepers across South Africa would be capable of building up to 5 or 6 super/honey chambers on a brood/deep chamber. Capensis beekeepers can do the same as the beekeepers of old south of the line. There is absolutely nothing stopping Capensis beekeepers from repeating the practice of old. The Scutellata holds no threat in reverse for the Capensis in the South-of-the-line territory.
Source: P. Kruger
Content sources: P Kryger, U Strauss
Easy Buzzing bee course
Going forward the bee course dates for Joburg are:
July 25th in Midrand. Then 5th Sept.
Bee WARE RETAIL open in Centurion from 09h00 -16h00 weekdays. Sat 09h00 - 12h30.
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