Fall is not just honey harvest and smiles, its the toughest time for our bees here in the Southland. Varroa, Robbing, Starvation, even Usurpation all seem to hit hardest this time of year. The bees need our help this time of year the most. And on top of all that, we here at OC Beekeeping believe its the best time of year to requeen ! So lets talk about what we can do to help our girls survive and flourish.
Varroa. If you treated all the way back in Spring its absolutely time to check on mite levels. The alcohol wash is by far the most accurate, sugar shakes can be off as much as 50% unless your really really shake and roll the bees. You have to get the bees angry enough to heat up their bodies, so a gentle roll leaves many mites behind. Some folks even think many bees die later from a vigorous sugar shake. Swallow hard and sacrifice the half cup of bees with an alcohol wash to get an accurate count. If you get 0 or 1, your in great shape. Otherwise, you should treat with some sort of mite treatment.
Which one ? The first factor is weather, above about 85 degrees your pretty well stuck with Amitraz (Trade name APIVAR). Remove any honey humans are going to consume and give one strip for each 5 frames of BEES. Get it into the brood nest where nurse bees with come in contact with it. Amitraz really takes about 7-8 days to start to lower mite levels. Hopefully, your not working with a mite load of 20 or above, if so use a faster treatment such as Apigard or Mite Away Quick Strips or they may succumb to viruses before you get the mite level down. Both of those have a temperature restriction, so you balance what you need with what your available options are. If the temperature is cooler you can use any one of the treatments available, APIVAR, APIGUARD or FORMIC PRO. Some beekeepers may choose to use Oxalic acid, either through a dribble or application via towels, although its not yet approved for California. Look on the web or see Randy Oliver's Scientific Beekeeping site for more information about Oxalic acid application. For really detailed instructions on any of the treatment methods, drop by the shop for advice, we find the actual labels don't give you good results here is SoCal.
The bottom line about Varroa is you must address it. You will be sad with the results if you don't.
Robbing. Get those entrance restrictors in place ! We like to use screen instead of wood and only leave about 3/4 of inch of opening. Until you see a traffic jam, its fine. We dont leave it in place all year, the bees can really clean the bottom board themselves if you leave it off in springtime. We sell inexpensive pre bent screens if you need it. Leave off the box feeders this time of year, we see it really spreads the scent of the syrup because of all the surface area. Also, don't add anything to your syrup. It greatly increases the odor for robber bees to detect you are feeding. For us, we switch to a semi dry mix called winter patties. It does not seem to incite the robbing that can occur in some yards this time of year when there is very little forage, and it is very low in protein because we aren't trying to encourage the colonies to build up. We switch to Ultrabee full protein patties in January for spring buildup.
Starvation. Each colony should have a minimum of 4 frames of honey for stores at the end of August. This applies to SoCal, more if your in a rural location (no irrigated landscape) or one that gets snow. Look for some pollen too. If you don't see any pollen frames, give them some pollen substitute. You can lift the hive from the back (tilt up the back) and it should weigh about 30 lbs. Not enough honey ? Feed them syrup or steal honey from some another hive. Its common to have to move honey or pollen around between hives to get all our hives provisioned well for Fall and Winter.
Usurpation. This happens infrequently in suburban locations but is a problem in rural areas. A small swarm with queen moves into the beeyard, often settling of a hive top, side or nearby bush. Usually about the size of a softball, it takes to the air again and lands at the entrance of one of your hives. If they can fight their way in, they ball the queen of the existing hive and kill her. And they ball the invading queen to protect her from the local bees. After about a day she is the 'new' queen. Did you ever have a queen lose her paint without even a trace of it left on her and now the bees are acting different ? And there were never any queen cells so they couldn't have replaced her themselves ? Well, its likely you suffered a takeover. What can you do about it ? There is little to do to protect against this but keep hives strong, combine the weak ones so its more difficult to overpower. And keep a eye on the beeyard and kill those little tiny swarms that move in. Just spray them with soapy water or knock them onto a white hive top and look for the queen. Its easy as there only about 300-400 bees. Smash her when you spot her, don't wait. The swarm won't really be able to reorganize after that. Those little swarms can really screw up your colonies, don't try to save them.