Apologies. I was very busy for the last month and failed to provide a “what to do in April” Post in time. There is no point in providing it now and we might as well skip it altogether.
In a nutshell, things that need to be done in April/May aren’t too different from March. The beehives are winding down and preparing for winter or have already prepared. They should have plenty of stores now (if not, there is still time to feed them sugar syrup) and most importantly the mite load should have been reduced weeks ago, to enable them to raise a healthy generation of long-living winter bees.
As the season progresses and we head through autumn into winter what happens is that the bees reduce the amount of brood rearing they are doing. With regards to varroa mites this means if there still is a significant amount of infestation in the hive (either due to re-infestation, which totally is a thing or because summer treatments were not as efficient as you thought they were), all those mites suddenly have a lower number of brood cells to infest. Thus, the ratio of infested cells goes up and more and more short-lived sick bees emerge. This can lead into a downward spiral and cause hives to die off despite receiving proper summer treatments. Inexperienced beekeepers might blame their losses on queen problems or cold temperatures (or even wasps)
Depending on local climate, and genetics queens might seize the rearing of brood entirely. Especially after the first few nightly frosts. For example, at my apiary in Dunedin pretty much all queens have all but stopped laying eggs, as we had a patch of horrible weather for the past few days and before those night-time temperatures reached quite low. Inexperienced beekeepers could interpret this behaviour as signs of queen problems but that is not the case in this instance.
All but 2 hives, which were late splits have good strength, all hives have plenty of stores (honey and pollen) and most importantly their behavior when doing an inspection is calm. Trying to find the queen and confirm her presence would give some ease of mind to less experienced beekeepers, but I have found that whenever I really want to to find a queen, I won’t.
Minimal or stopped rearing of brood is a godsend with regards to varroa control as any time window where there are no more capped brood cells means that all mites inside a hive are phoretic only and can easily be killed by one application of oxalic spray or vaporization, ensuring low infestation levels well into spring.
As brood rearing is reduced and there will be less overall capped cells it is also a good time to do inspections for diseases (some people will have to do AFB inspections in autumn as part of their DECA). Since there is less capped brood any lone capped cells with unhatched/dead larvae in them will stick out and be easy to spot, let us hope they are just leftover signs of PMS and not AFB. Of course, in the instance that you do find AFB make sure you do the right thing and burn the hive and notify the AFB Management Agency.
Assuming your hives are healthy and well fed there is not much else to do, which means finally the time has come to do all those mundane tasks that you haven’t found the motivation or time to do them during summer. Tidy up your shed/garage where you store your beekeeping stuff, clean, and repair any unused hive ware. Scrape or melt the beeswax off old frames before waxmoths leave a mess, dispose of mouldy frames with dead brood in them (ideally by controlled burning).