Master the Varroa Mite in Australia

The typical number of treatments used will vary according to your local climate. However, based on NZ we know that New Zealand beekeepers typically treat 3 times per year. We can safely assume you will need to treat 3 times per year in Australia and possibly more if you live in a warm climate that doesn’t have a cold winter.

Although there are organic methods to managing Varroa mite in your colony, a study of New Zealand beekeepers showed that those that used only organic treatments experienced a loss rate of 40% each year. This dropped to 20-30% when using 1x Organic treatment and 1x Synthetic treatment and further dropped to sub 10% when using 1x Organic treatment and 2x synthetic treatments. We therefore recommend using a mix of treatments on rotation to keep your colonies healthy.

FormicPro, which is an organic varroa mite treatment can be used to treat your hive with honey supers on in the temperature range of 15-29.5 degrees. It will not leave residues in your honey. You may also choose to remove honey supers and treat using synthetic strips, particularly if your hive is declining due to varroa. Reducing your boxes and treating will help your bees keep warm while the treatment takes effect.

Varroa mite kills a hive by the spreading of viruses. As varroa mite breeds below the cell capping, the number of varroa mites per cell increases over time. When the mites are feeding on young larvae, they can transfer multiple deadly diseases which can result in dead brood or weakened nurse bees which are unable to carry out their normal duties. Eventually the population collapses when varroa mite numbers get in the thousands

It is almost certain that your hive will eventually die of varroa if left untreated. Initially, your hive will handle high levels of varroa as the viral load hasn’t built up within the colony. However, it is extremely unlikely based on other countries experiences that your colony will have any resistance to mites

Not using the treatments for the full length of time or half dosing the treatments will result in resistance to the treatments very quickly in Australia. In parts of the USA, treatments weren’t rotated and synthetic strips were only half dosed. This resulted in rapid resistance to the treatments in parts of America. Please always use the treatments as per the instructions.

All approved products in Australia have proved to work very well so far in Australia. It is important that every beekeeper uses the treatments as per the instructions so varroa mite doesn’t build up resistance. Rotation of treatments also helps to prevent resistance to varroa treatment products.

Each treatment, either organic or synthetic uses what is called a Method of Action (MOA). MOA is how the treatment kills the varroa mite. Each treatment effects different parts of the varroa, for example the mouth piece. If a treatment is 99% effective and there are only a few mites leftover, these mites may have only been exposed to part of the treatment and could in theory build up resistance. So, we use a different treatment the next time which then wipes out the genes of those left over mites with a different MOA. Some products, such as Formic Pro uses multiple MOA’s which means there is presently no resistance detected world wide.

Officially the most accurate way of determining varroa mite numbers in your colony is with an alcohol wash. You can also inspect your drone comb regularly and look for the reddish brown varroa which prefers to breed in drone comb. You can also insert synthetic strips for 48hrs with sticky mats placed at the bottom of your hive. This will mean and varroa mites on the outside of the cell capping will fall to the sticky mat which you can then inspect.

Integrated hive management is the best way of managing varroa. It combines things like mesh bottom boards, regular surveillance, chemical and organic treatment options for the best possible outcomes for your colonies based on the best possible data available.

When varroa mite emerges from the cell cappings after their breeding phase, they move into their dispersal phase and look to latch onto a bee. When doing this, around 20% of varroa mites have been found to fall. Using a mesh bottom board/base ensures that the mites fall through the mesh and get chilled and die. Varroa is blind and relies on smell so they have a difficult time getting out of the trays. With a standard base, varroa have another shot at attaching themselves to a bee. Screened bottom boards are therefore a passive or mechanical way of helping to keep your varroa mite levels lower as part of your integrated management plan.

It is highly unlikely that your bees will have any natural resistance to Varroa mite. Without regular treatment they will likely die.

You can introduce a brood break in a number of ways. Using a queen cell to replace your queen is one way to expose all the varroa mites under cell cappings to synthetic strips. You can also confine your queen or even move your bees to a cold area so the queen stops laying or reduces her laying.

During the first few years of varroa arriving in Australia, nearly all colonies in the wild will die out. As they do, they will be strong vectors for varroa to spread and can spread varroa to your colonies. This means that you need to be extra vigilant even after treating, to check that you aren’t hit with a ‘mite bomb’ that quickly reinfests your colony.

Potentially yes, but the numbers would be very low. You will be unlikely to see wild bees in Australia after the next few years. Wild colonies are almost unheard of across the globle now.

7 days. You don’t need to be back to remove the treatment at the end of the 7 days. This can be done at your leisure.

6-8 weeks. Strips must remain in the hive for the full length of time as they require contact with varroa to be effective

8-10 weeks. Strips must remain in the hive for the full length of time as they require contact with varroa to be effective.