I have been fighting SHB (small hive beetle) all summer. Now that my honey harvest is over, I am reflecting on how the FLOW frames and hive architecture/construction harbor SHB and make it difficult for the bees (and me). I’ll list my problems/observations and suggest three solutions.
Once the FLOW super was put in place, I noticed that the bees corralled the SHB in empty cells. I doubt any nectar/honey gets stored in those cells as long as the SHB survive. After honey harvest the bees kept SHB corralled in the open cells. Any control is hampered by the available open space that the SHB take advantage of. A good trap (see #2 below) is needed for season-long SHB control.
SHB are dimorphic; i.e., the males are smaller than the females. Small SHB might fall through the screened bottom board, but the small screen opening only allows immatures and males to fall through, not females. Increasing the screen size opening (#7) allows both sexes to fall through. A SHB trap of some design could be incorporated into the bottom board design.
The gabled hive cover has many nooks and crannies where SHB can escape the bees. The roof looks great, but does more for SHB than the bees. Caulking or sealant might solve the harboring, but a simpler design might be in order.
Hi Paul, I consider myself to be an expert on SHBs. I’ve been dealing with them since they arrived here in the year 2000.
The main thing for SHBs is to keep the colony strong with workers. Beetles will use empty flow cells to hide in, however they also use empty traditional cells to hide in. If the bees want to store honey in the cells the beetle are hiding in, they’ll easily drive them out. Then they’ll hide somewhere else.
You are correct in saying that the roof needs a lot of caulking or sealing to reduce hiding places. However a hive needs hiding places for beetles to hide in, otherwise the bees will spend too much time chasing them around in circles.
There IS one trap with the flow frames I observed the other day while inspecting a clients flow hive. I noticed a whole section, about 6 cells wide & it extended from the top to the bottom with residue SHB larvae slyme stain. That section was empty of honey, plus some beetles were hiding there. The SHB larvae exudes a slyme which is a bee repellent. That’s the reason that area was free of honey. Even though the rest of the frame was full of honey & capped
The trap is when the honey is harvested at the hive, bees can get stuck in the cells. Those trapped bees are a target for the beetles to lay eggs in. If there is not enough workers to quickly overwhelm the beetle larvae & clean it out, that section will get slymed by the beetle larvae.
Therefore my suggestion would be to harvest the honey away from the hive.
Edit:- Another area of concern is when flow frames flood onto the brood while harvesting honey.
If the flood is significant, the bees that normally chase beetles spend a lot of time cleaning honey off themselves as well as trying to clean up the honey spill. While those workers are busy doing that, it allows the beetles that would normally be hiding, an opportunity to quickly lay eggs in the bases of the brood. This can/has quickly turn/ed into a slyme-out.
Hi Paul we modified the corflute on the bottom to have small timber surround with lime or DE in it. A small gap at the bottom allows beetles to enter but not bees. Any beetles or moths moths lavae get coverd with the lime and die. Any beetles etc in the hive get driven down also except as you have mentioned those that are too big.
My thoughts were to let them in the bottom and get trapped. Seems to help us.The new flowhive has a similar setup. Search our posts for the modification.Thanks for sharing you observations.
Goodluck.
The SBB mesh on the Flow hive Classic is actually #7 hardware cloth - I checked with the manufacturer. The new Flow hive 2 has a beetle trap built in (Multifunctional Tray in the image below), as you suggest.
Allowing SHB to enter from the rear and get trapped would definitely help. The SHB are masters at finding opportunities to enter through the front even when it is crowded with bees. If the bees could chase/harass the SHB through the screened bottom board into the trap it could help control the pests on two fronts.
I pulled my bottom board from my classic and found the the large SHB would not fall through. If it is a #7 screen (I’m checking on it) then a #6 screen might be in my future.
Last year I didn’t notice many SHB, but this year they arrived early and in large numbers; took me by surprise. I spent the summer trying different internal and external types of traps with variable results. I definitely underestimated their resourcefulness in infesting a hive.
I checked out the new Flow hive with the multifunctional tray and screen. I like it and maybe those modifications will resolve the SHB problems for that design. I’m guessing that the multifunctional tray can be filled with hydrated lime or diatomaceous earth.
I too checked my Flow SHB and discovered that it is a #6. Doing a bit more investigation I found that half of my non-Flow SBB’s have #8; they were the culprits of only allowing males and immature SHB through. With chagrin I retract my statements about the Flow SBB. A #7 screen might still be a solution for those with the Flow classic SSB, if they find small bees in their SHB traps. Thanks for sharing your thoughts and info.
Hi Paul, when you say “large numbers”, how many are we talking? I see large numbers at times, however it never phases me. I don’t use any traps of any kind. I just squash the ones I’m able to while doing inspections.
The main thing to do is keep the colony strong, as I previously stated.
Also get to know the enemy. They lay eggs in brood, dead or dying bees & pollen. Drones don’t do any defending. Once we understand that, we can carryout our beekeeping activities with peace of mind, making sure that they don’t have access to any of those 3 places to lay eggs in.
Be aware that they can also breed up outside the hive. It’s advisable to not leave anything sitting around outside the hive that they can lay eggs in. They also lay eggs in slumgum (residue after processing wax).
I pulled off a 6 frame super after the bees cleaned it up and set it over a SBB with #6 screen to see how many SHB would be trapped in a tray of water/cooking oil. After 1 day over 160 SHB were trapped. I pulled the frames out and found the bees were still trapping SHB. I shook off the bees, frame by frame, over the screened trap and easily picked-up another 50 SHB. I performed the same for two more Flow supers, with somewhat lesser numbers. All three hives are very strong and spend a lot of time corralling the SHB in the Flow frames and on top of the inner cover and hive cover. Don’t know what a “safe” SHB number per hive would be. Thanks for your thoughts and time.
Nice of you to retract, but it shouldn’t be “with chagrin”! No failure or humiliation here, you successfully worked out the cause of your SHB observations. Such is the nature of real science. Nicely done, and you have learned something. Hopefully your under-hive beetle traps work, if you ever use any. I have SHB, and I don’t use the trays. Just a hive tool, careful handling, and occasional frame-hanging traps if numbers seem higher than normal.
I don’t think anyone really knows. But if I have to kill more than 8 SHB during an inspection, or I see SHB larvae in a pollen patty (gross), I hang traps. Usually just one in the top box of the hive. Of course I throw out the infested patties too - only had to do that once. Truly vomit-worthy.
You’re welcome Paul, I opened a hive to find about 500 hiding in the lid & under the hive mat once. I must have squashed 200. I still felt confident walking away from that hive, knowing that the remaining 300 can’t do any damage. There is always lots of beetles in that hive because it stands alone. No other hive to share the numbers.
“safe” SHB numbers is only dependent on how well we work our hives with SHB in mind. One pair would be unsafe if they had easy access to something to lay eggs in, such as @Dawn_SD’s patty, for example cheers
Jeff- I had a question for you about beetles and solid bottom hives: do you ever observe bees chasing beetles out of the front entrance? It occurred to me that having no landing board might be an advantage in such a situation as the beetles would be ejected and fall directly to the ground.
Hi Jack, I haven’t observed that. Think about what you just said. Beetles can crawl, fly, whatever it takes to get somewhere, while they have strength.
Wouldn’t you think that if a beetle got kicked out, it would get up & fly back in again.
It would be good if someone could figure out a biological solution like that for beetles, a combination of chickens, geckos, etc. We don’t yet have beetles here in Adelaide but my brothers hive is situated in his chicken coup- I wonder how much chickens alone would help to control beetles.
The new Flow hive 2 has a beetle trap built in (Multifunctional Tray in the image below), as you suggest.
No failure or humiliation here, you successfully worked out the cause of your SHB observations. Such is the nature of real science. Nicely done, and you have learned something. Hopefully your under-hive beetle traps work, if you ever use any. I have SHB, and I don’t use the trays. Just a hive tool, careful handling, and occasional frame-hanging traps if numbers seem higher than normal. 
cheers