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March 2021

Spring is in the air and March often marks the beginning of the active beekeeping season in our area. However, at the moment the weather is still very changeable and there is a chance of an Arctic blast during early March. As I write, the sun is shining and temperatures are reaching 16 -17°C but the long-range forecast is predicting possible snow. Conditions can change rapidly in March so apiary visits now need to be weekly checks. If conditions improve towards the end of the month, on a warm, windless day when the temperature is above 14°C, it would be prudent to make a first check inside your hives to see how each colony is faring. However, it soon goes cold in the late afternoon and night time temperatures can still be very low so make any checks really quick – a matter of a few of minutes. The bees have worked hard to build up their internal hive temperature and letting it out creates even more stress when the colony is already under pressure – and stress leads to disease taking hold

Warmer temperatures will also bring other pollinator queens out to feed and establish their new nests – this includes any Asian Hornet queens that may have escaped detection, last year. AH queens may be seen stripping wood off the bark of trees or wooden fences to chew up and make their primary nests. At this time, they need a sweet carbohydrate diet so traps should be baited with something like pressed apple juice or sweet alcohol and placed close to where you can observe them daily in order to report a finding. Spring trapping before a new colony produces foraging workers, is our best weapon against this predator.

More Brood than Workers

This month is critical to colony survival. Honey bee queens will be increasing their rate of lay so there will be a lot more brood to feed and keep warm. Whenever possible, bees will be leaving the hive to defecate, fetch water and clear out the older dead bees as well as bring in pollen – a sure sign that the queen is laying and new brood needs feeding. The temperature in the brood nest now needs to be maintained between 34-35°C by the rapidly diminishing winter bees. With this demand for energy there could be a problem as although the spring blossom is appearing, heavy rain can wash away pollen, dilute the nectar and if we get the cold snap the blossom could die off. It is not unusual for colonies to starve between March and April and as brood numbers exceed workers to care for them, it requires beekeepers to make weekly visits and if in doubt feed. Stick to fondant until it is much warmer. It is still too early to chance feeding with syrup a s a change between day and night time temperatures, can lead to pressure causing a contact feeder to dollop freezing cold syrup over the cluster. If you’re aware brood rearing is well underway in your colonies and a cold/ wet spell damages plants, you may need to consider feeding pollen patties to tide colonies over. However, take care not to use pollen patties to over-stimulate your bees into rearing a large foraging force before there is a flow for them to forage on. Beekeeping is a funny business – it’s all about planning but also observing the weather, the available forage and your bees then taking action accordingly – no two years are the same!

Spring Dwindle

Take the time to watch your hive entrance. Pollen going in is a good sign that the queen is present, laying and the colony building. A hundred or so dead bees outside the hive is normal at this time of year but if you see piles of dead bees in their thousands and no movement or very little movement when other hive entrances are buzzing, all might not be well. Take a quick look inside to see if the colony has died out. As mentioned last month, close the hive right up to avoid other bees robbing it and potentially spreading disease, then remove as soon as possible. Away from the apiary, try to ascertain why this happened: has the colony starved, was it diseased or just too small to keep up the core temperature of the cluster? Dispose of the frames, bees and debris by burning, then scorch the boxes thoroughly before reusing.

However, if you find a colony that is small, place fondant on the top bars directly above the cluster and surrounded it with an eke, so the bees are in contact with food, then replace the crown board above. Also, close the entrance to one bee space to avoid robbing and make a note in your records to do a thorough disease check as soon as a warm day allows. The adult bee gut disease, Nosema is one of the main dangers at this time of year, as it prevents the affected workers from processing pollen to feed the brood as well as shortening their lives. This can often be the cause of ‘spring dwindle’ when the colony fails to build beyond 3-5 frames and is a very common problem. Even if you see no signs of faecal staining/dysentery, be aware that Nosema Ceranae is now just as common and displays no visible symptoms. If you do suspect Nosema, as soon as the weather permits (usually April) move your bees into clean, sterile equipment using a Bailey Comb Change for a weak colony. This is not the same as a normal Bailey Comb Change and if unsure of this method, you can always ask someone who has taken the Honey Bee Health Certificate. Useful booklets every Beekeeper should have are ‘Common Pest, Diseases and Disorders of the Adult Honey Bee’ and ‘Managing Varroa’ both of which can be obtained for free from The Animal & Plant Health Agency or downloaded from the BeeBase website:

First Quick Check Inside

Towards the end of the month, if the weather is suitable, it’s time to check what’s happening inside each hive. Hopefully, if all continues to improve with the pandemic situation, you may be able to work closely with another beekeeper to ensure you carry out hive manipulations as quickly as possible, plus get advice if needed.

Remember worker bees take 3 weeks from egg till they emerge and another 3 weeks as adult bees inside the hive so it is these early eggs that will become the foragers once the spring flow is underway. On a warm, windless day (above 14°C) when the bees are flying well; suit-up, have spare equipment ready and smoke the entrance gently. Do a QUICK check to assess what is going on but leave your first full inspection until temperatures are constantly higher – usually April. Remove woodpecker protection and mouse guards, also replace the hive floor, which may have a number of dead bees the ‘undertakers’ have been unable to remove. Take this opportunity to place mesh around the legs of your hive stand to prevent possible Asian Hornets from zooming out from underneath to snap up foraging bees. Your aim, for this first inspection, is just to check the colony has made it through the winter well and is expanding. Be on the look-out for where the brood is. If there are empty frames with no brood or stores, move these to the outside of the box to remove any gaps and keep the brood in contact with the colony’s stores but do not leave the queen without anywhere to lay and expand the nest. Also, there should be good patches of eggs, larvae and worker brood in a regular pattern.

Quickly decide whether each colony has enough stores, space to expand and the queen is laying properly. If you find lots of drone brood in worker cells, either the queen is failing or you could have laying workers. Make a note to read up on each scenario straight away or ask more experienced beekeepers for help so you can rectify the situation before the colony is lost.

During this first check, only keep each colony open a very short time. You do not need to examine every frame or see the queen but try to estimate the size of the colony and number of brood frames occupied. Update your records to show what will be needed next visit, as well as give you a base line to compare against and ensure each colony is expanding.

Varroa Loads

Due to the cold weather this winter, many of us were able to treat our colonies with a legal oxalic acid product while they were clustered and broodless, so now is a good time to test its effect and monitor varroa levels by inserting a varroa board underneath the open mesh floor of your hive for about a week. Varroa drop can vary from day to day depending on the weather and how active the bees are so it is better to leave the varroa tray in for several days and work out the average drop per day. Before inserting, draw a roughly 5 x 5cm square grid pattern on to the plastic Correx Varroa board with a permanent marker. This makes it much easier to tot up the offenders and get a more accurate count. You can use the BeeBase calculator or NBU booklet to check the drop for the time of year but a high average above 8 per day, means that some intervention will be needed.

If you were unable to treat with oxalic acid, it is likely that varroa infestation is going to build up rapidly so plan your Integrated Pest Management (IPM) and if you are intending to use Apiguard, the 4-6 week cycle of treatment needs to happen ahead of supers going on, as soon as temperatures are above 15°C. Whereas MAQS needs one treatment over 7 days and can be used above 10°C or with supers in place. Avoid using the same treatments as last year and only use when the temperature is high enough for the product to work effectively, to avoid the mites building up resistance. Alternatively, you may decide to use bio-technical methods that do not require chemicals. When it’s warmer (not this month), if colonies are free of Nosema and have built up well, Shook Swarm is now the preferred method for many beekeepers and it has been shown that strong colonies quickly catch up on clean comb.

Swarm Preparations!

Be aware that a sudden change to better weather could lead to rapid build-up and early swarming. Milder conditions may mean you can begin feeding with sugar syrup to take advantage of a spring crop. It is recommended that sugar syrup should be made up in the strength of 2kg of sugar to 1.25L water (1kg sugar/625ml). However, feeding syrup now causes rapid expansion in a healthy colony and can lead to early swarm preparations if the hive becomes congested. Ensure the brood area always has sufficient space for the queen to lay and create extra room for storage by adding supers early. Now is the time to make sure you have plenty of spare sterile equipment and frames made up so you can put all your colonies on to clean equipment when necessary and be ready to carry out an artificial swarm at short notice. Don’t forget to have supers ready – this month will be about watching and responding to the long range weather forecast as well as what your bees are communicating to you!

Check List for March

  • Check weekly & feed if necessary
  • Watch hive entrance for activity, especially pollen going in
  • Close up hive completely & remove if colony has died out
  • On a sunny, calm day above 14°C carryout quick inspection
  • Remove mouse guards and woodpecker protection
  • Put hive on to a clean floor
  • Place mesh around hive legs & hang up AH traps
  • Insert varroa boards & decide on IPM intervention
  • Start recording for the new season
  • Begin feeding with syrup, in a contact feeder, once consistently mild
  • Avoid early swarming by preventing congestion in the hive
  • Have spare equipment ready: for an artificial swarm + supers.