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In my apiary, I consider robbing screens a necessity. Since I began using them about ten years ago, I haven’t had a single case of robbing. Prior to that, it was an annual fight to keep things under control.
This year in particular, I’ve had many beekeepers write in a panic asking how to stop the robbers. But, in truth, it is a zillion times easier to prevent robbing than it is to stop it.
Robbing usually begins in a nectar dearth when foragers from one colony find a hive that is weak or poorly defended. They detect the scent of stored honey inside and try to steal it. Fighting ensues, often with many deaths on both sides. If the defending colony becomes overrun, the marauders are free to take what they want.
Ripped and ragged cells
Robbing bees rip open honey cells instead of opening them nicely, honey flows out of the damaged cells, and the scent of honey is further disseminated. The scent will attract not only more bees, but other predators as well. Both the scent of honey and the odor of dead bees will attract hornets and yellowjackets. Once robbing begins, it feels like an avalanche. Everything gets worse in an overwhelming hurry.
Beekeepers can inadvertently initiate robbing by spilling a drop or two of honey or sugar syrup in the vicinity of the hives. Anytime you open hives in a dearth you are asking for trouble if you don’t take preventive measures.
Following the scent
Both wasps and honey bee robbers follow the scent of the hive. Since they don’t live there, they don’t know where the “door” is, so they sniff around. You can often see robbers examining the area just under the roof, the seam between two boxes, loose box joints, the area under the screened bottom, or any other place where the scent of the hive can leak out. They will keep trying and trying until they find their way in.
Robbing screens work by diverting legitimate hive traffic to an opening away from the real opening. The new openings are usually five or six inches above the main opening, and they are positioned above an impervious surface that prevents the hive odor from escaping.
However, a screen lower down near the “real” opening, allows the scent to escape. The robbing bees detect the scent through the screen and spend their time trying to find their way in. They don’t go near the diverted opening because it is covered by the impervious surface. Once the robbers move too far from the screen, the scent weakens, so they turn around and go back down.
Robbing screens traditionally have two diverted openings that open and close. Normally, you start with one open and one closed. If some robbers manage to find the opening, you can switch them and the learning process has to start all over again.
The first time I used robbing screens, I was skeptical, but they really do work. However, they work best if robbing never starts in the first place.
Use robbing screens early and often
I install my screens just before honey harvest because harvesting can sometimes begin a robbing spree. Then I leave the screens on until the fall when cold weather keeps the bees inside.
However, with nucs, splits, and captured swarms, I use a robbing screen from day one. These colonies are often small enough to get attacked by robbers during early spring or when there is a temporary lull in the nectar flow. I used to worry about those small colonies, but now I just add the screens proactively.
Types of robbing screens
A few different styles of robbing screen are on the market, but my favorite is by BeeSmart Designs. They are easy to put on and take off and they fit either 8-frame or 10-frame equipment. They come with push pins for attachment. If you buy the BeeSmart Designs ultimate bottom board, there are attachment points for the screen as well. Best, with the BeeSmart bottom board, the robbing screen can be replaced with a special mouse guard in the fall.
One of the problems with the wooden-framed robbing screens is that if you use a slatted rack, the rack and the lower brood box must be lined up precisely because wood doesn’t bend around the edges and you can end up with a space at the sides large enough for a yellowjacket. You still need to have things basically lined up with the BeeSmart screen, but I find the plastic is a little more forgiving and easier to use.
Other advantages of a robbing screen
One of the overlooked advantages of a robbing screen is that it keeps out drifting bees as well. This can have a significant impact on varroa control. We know that drifting bees are one of the primary means of varroa dissemination. Drones especially are not very particular about where they bed down for the night, and they can easily travel from one hive to another. And because they’re drones, they’re usually allowed in.
If your colony is already overrun with mites, this might not make much difference. Perhaps you lose a few mites when drones leave, and you gain a few mites when drones arrive. However, if your mites are under control, drifting bees can make a huge difference.
In fact, if you have no mites to start with, one foundress mite can multiply into a sizeable infestation in one season. But if three foundress mites move in, they can produce three times as many mites in the same length of time. Multiple and repeated introductions can overwhelm even mite-resistant bees.
To me, it seems that robbing screens should be part of an IPM program to keep varroa under control. It is an additional technique we can use that is inexpensive, easy to implement, and chemical free. When paired with other IPM techniques, robbing screens can be a useful mite control tool.
Honey Bee Suite
How do the bees get the dead out? Are they able to haul the bodies up to the opening for disposal? I’ve had problems with closed-bottom robbing screens–they had trouble cleaning house.
The bees can carry the dead out, just like they do when they’ve only got a top entrance.
Thanks Rusty, I have been thinking about robbing screens for a while now. I have a weak colony that is now awaiting a queen cell to yells a queen. This helped me to be decisive about a robbing screen for it…and soon!
Maybe I will put them on my other hives right before I harvest.
Good ideas, please keep posting them.
Rusty. Interesting article. Begs the question – can’t figure out from the pictures – is the hive opening the usual full width across by 1/2″ or so to start? So this covers the whole opening and forces the bees to find a new entrance/exit up at the top? Maybe you mentioned but needs to be put on in the morning before the workers leave or they won’t find the new entrances? Sorry for my confusion. This time of year I’ve usually constricted my entrances down to 1/3 opening to hope keep out yellow jackets. Mike
No, I have entrance reducers on under the robbing screens. I think some people take out the entrance reducers, but I think if robbers are bad the first line of defense is the robbing screen. If some of the robbers get in, the second line of defense is the reduced entrance. Most of my hives are reduced to about three inches and then the robbing screen added. I never open the entrances all the way across.
As for putting them on in the morning, that’s what the instructions say. But I put them on any old time. Once one of the bees finds her way in, she will fan the rest in with pheromones. So I don’t do what the directions say on that.
Rusty, have you ever used a Brushy Mountain Bee Farm robbing screen? Because that’s what I have and I get the impression that it is confusing the legitimate hive-dwellers. It’s been on for over a week and there are always a bunch of bees crawling on the inside of the hardware cloth, apparently sensing fresh air and believing that there must be an exit there, but of course not finding one. Although, there are also many bees using the two doors of the robbing screen. (I am using a robbing screen because it’s a new package, but with both doors open because we are not in a dearth. I also was just curious to see how bees react to having a robbing screen put on their hive.) Is it possible that some of the bees are actually still confused and some of them figured it out really fast?
I took it off for a few minutes last week, after it had already been on for two days, and a bunch of bees came pouring out the entrance reducer, almost as if there had been a roadblock and the traffic jam behind it was clearing out all at once. I plan to try that again next time I go see them. What do you make of this?
Also, since I put on the robbing screen, there are always a bunch of bees hovering in front of the hive, weaving back and forth facing the hive like they are trying to remember how to get in. Have you ever had this type of bee-havior related to putting on a robbing screen?
I watched them at dusk the other day and it seemed like all the hovering bees made it back inside before dark. So they can’t be that confused. I just don’t understand why adding a robbing screen would make 30 to 60 bees stand around (or hover around) all day doing nothing, just staring at their house like there is something wrong with it. Not even flying in circles for orientation flights. Not facing outward to guard the hive (the hoverers completely ignore me). Just swaying back and forth staring at the front of their hive. I don’t get it.
Looking at this page again 3 years later and replying to myself in case someone reads my long comment. It was all orientation flights. The confused bees inside the screen every day were just the brand new foragers that were graduating each day.
I also keep robbing screens on all year. Robbing is one of the biggest threats any colony faces in an apiary with hives in relatively close quarters. Yellow jackets and other wasps and hornets have been bad for me this year and I am very grateful for the robbing screens. I make my own out of scraps 3/8 or 3/4 inch plywood and #8 screen. I have the one small 3/4″ entrance at the top left side and a larger 2-3″ on the bottom right which is closed or reduced most of the time in the spring and summer. But during our May and September nectar flows, I leave both open. If you spot a problem it is easy to close up the hive until everyone gives up and goes home.
As you said they really work.
Whatever we (readers) get to glimpse of them, your hive stands are beautiful, functional, and seem sturdy and well made … Inspirations for sure.
Thanks, Paul. That’s because they’re built and designed by a mechanical engineer!
Thanks once again for your valuable info, I’m always learning from you. ?
I’d love to replace my current DIY robber screens with these, but can’t see to find a stockist in Australia, and shipping costs from US seem very high. Do you know of any stockists nearer or in Oz. Cheers Kaz
I’m sorry but I don’t know of any. This product is fairly new and it will probably take a while to get better distribution.
I have the same thought as above, I can’t figure out from the pics where the entrances even are!
I, too, use robbing screens all year round. I use the wooden w/the screened front, but over the screen I usually add house screening so that the bees cannot feed each other thru the mesh. In the past, I have seen robbing bees feed each other thru the mesh, so that is what prompted me to add the screening. On the nucs, I too use both, the entrance reducer and the robbing screen and use the top entrance when the nuc is young and convert to the bottom entrance as the nuc strengthens. One way people can tell for sure if robbing is going on, is by looking at the bottom board, if it has wax pieces all over the place, then you know that the bees are uncapping that honey. Also, I try to take most of the excess honey off of the hive before robbing season starts, and then put it back toward the winter maintenance “bedding” time. This way, it reduces the aroma of the hive a bit and keeps robbing to a minimum. Oh the joys of beekeeping ! Thanks for this posting, I think people under value the uses of robbing screens. I leave them on all year long except on the huge mass producing hives that can pretty much take care of themselves!
If you follow the link you can see a good diagram of the robbing screen.
I agree that harvesting before the dearth is the best alternative.
I plan on harvesting honey in mid September. Should I reduce entrance and put robbing screens on after harvest? Should I leave them on until spring?
I usually do it before because harvesting can start a robbing incident, but that’s up to you. There’s really no reason to leave them on during winter. In winter mouse guards are more important.
Hi Rusty! I am a new beekeeper (started in May with two hives) and I have a couple of questions about robbing screens. Is this something you use only when you have multiple hives? I live in NC and wondering when “robbing season” is? Just during the nectar dearth? Thank you! I love following your blog – so much useful information for a newbie like me!
Robbing honey bees can show up from hives a mile or two away, however the closer they are, the more likely is a robbing incident. Yellowjackets and hornets can be close by, too.
Great info thank you.
What does that do for good ventilation? In the summer don’t you need openings in the top too? Here in Virginia Beach it’s kind of hot.
Thanks for all your info,
You can use robbing screens along with screened bottom boards, screened inner covers, and screened ventilation ports. Your options for ventilation are endless.
I like my robbing screens too. Never thought of it being used as a mite control.
Hi Rusty (& everyone else),
Four years ago, I came across this article by Dr. Eric Mussen, UC-Davis, on robbing: http://entomology.ucdavis.edu/files/147611.pdf . I made four of the screens and they seemed to work as I haven’t had a robbing incident since. I’ve seen the occasional yellow jacket get in, but I see the bees take care of the intruder. This year, on a somewhat weak colony, I noticed some marauders getting in, but I solved this problem (seemingly) by reducing the entrance.
I have a picture of an even simpler robbing screen, but don’t know how to post it. I can email it to you if you wish.
You can email it to me here: firstname.lastname@example.org
How does one distinguish between robber bees and the girls who belong there. I am a first year beekeeper and bewildered by it all.
Please read “Robbing bees: questions and answers.”
Do you ever concern yourself with a robbing screen that covers the top entrance in the inner cover?
To stop robbing, I’ve put on a mouse guard over the top of an entrance reducer. Then added a very small piece of tin between the two reducing the entrance down to 2 openings for smaller colonies, and 3 or 4 for larger colonies. The round openings can be blocked by a single guard bee. It will create a bit of a bottle neck, but the additional bees at the opening seems to discourage the robbers from thinking about it. As the robbing stops, I increase the number of holes available till the number of bees at the bottle neck decreases.
I like this idea and it’s a good way to transition between robbing screen and mouse guard.
As for top entrances, I remove them when my honey supers come off.
Can you comment on when to put robber screens on vs mouse guards? I have robber screens on now but I was recently told that mouse guards should be on now as our nights are starting to get cooler. I recently purchased new mouse guards that are metal with 3/8 inch holes. I was considering using both if they fit after reading that you keep entrance reducers on. Your thoughts?
Thank you for another perfectly timed post.
I put mouse guards on when the bees begin clustering to stay warm, but you can use both. See the comment below by Boyd Young.
You said that they work really good with their bottom board. How do they work with standard SBB?
They work fine with a screened bottom board (SBB) or a solid bottom board (SBB). If you look at the last picture, you will see mine used with a screened bottom board.
When using year round do you use a top entrance when you’re in a heavy flow? Also do you use any type of top ventilation?
1. I have a top entrance drilled in each honey super.
2. I use screened inner covers for upper ventilation.
Just curious. When you use that BeeSmart bottom board, have you noticed any increase in washboarding/linedancing?
One of the theories on why bees do that is that they’re polishing the surface of the wood. Since that bottom board seems to have a textured surface, it might either confirm or dismiss that theory to some extent. If they want things smooth, they’d most likely be line dancing their butts off.
No, I haven’t seen any increase. One hive had a lot of washboarding this year but they did it on the front of the wooden brood boxes, above the bottom board and robbing screen.
Thanks for info. Here in the southeast bearding and fanning can cover the entire front of hive.
Yes. Here too.
I’m from the UK and all my hive floors are the same dimensions as the brood boxes etc. Unless I pay the high price of international shipping I cannot get a plastic robbing screen. My question is the wooden screens mostly seem to have the bottom corners cut out so to fit snug with the hive floor, this looks to work only with floors that extent out from the bottom of the brood box, do all US floors extend out like the ones in your pictures?
I don’t know if “all” US floors extend out beyond the brood box, but you can make a robber screen out of a piece of hardware cloth.
Saw these robbing screens on an earlier post of yours and decided I may prefer these over the wooden ones I normally use (which warp in the rain). So when I was at EAS I snagged a couple to try and I really, really, like them. Very easy to install and won’t warp!
In my apiary I’ve not been able to feed nucs or small colonies for years due to robbing. I’ve had to feed the large colonies and then give the filled frames to the smaller colonies.
Something I’ve wondered: if all of the colonies have robbing screens, don’t the potential robbers (who also come from a colony with a robbing screen) figure it out? I guess if they use scent to locate the entrance of an unfamiliar colony rather than prior experience (of their own robbing screen), it can work to have screens on all of the entrances.
I like your idea of feeding the large colonies and then transferring filled frames. That’s a clever idea.
I too have wondered about all the hives having similar entrances, but apparently bee learning is not like human learning. Apparently they go by smell regardless of what they “know” about the doorway arrangement at home. But yes, it seems odd.
I’m just about to move my apiary around 120 kms. I was going to close up the entrances with f/g screen and duct tape just before the move but I’m wondering if I can get double duty from these robbing screens by just closing both entrances for the trip. I haven’t decided if I’ll move the hives pre-dawn or post-dusk but I’ll strap and spline the hives first. Your thoughts?
Yes, robbing screens would work. In fact, they are very similar to what are called “moving screens.”
Since having a couple robbing incidences I also use the screens sometimes, but I also always reduce the entrances to 2-3 inches using house screen. Thank you for the great article.
Question: From looking at the picture, I wonder, do you overwinter in a deep and a medium?
Yes, this year I’m going to winter in a deep and a medium.
Hi Rusty, I know this has briefly been addressed above, and I really like the idea of the robbing screen, but it seems trash is accumulating at the entrance and bees are not carrying it up and out. It’s the end of winter here now, so no dead bee material, but they are carrying out sugar that I put in the vivaldi board feeder. That is accumulating at the entrance. Any thoughts?
You could just remove the robbing screen and sweep away the debris. I often clear the bottom boards at the close of winter regardless of whether I use a robbing screen.
I checked out BeeSmart Designs for the robber screens but didn’t see them for sale. Another source?
The links in the article take you straight to Blue Sky Bee Supply, where you can purchase the robbing screens.
Jackie, I talked to BeeSmart at EAS and told him the screen was not on his website and he said it was hard to keep the site up-to-date with new products. Use the link Rusty provided.
The first time I saw a wasp land on a super I had just set aside, I realized how open and vulnerable that box was while the rest of the inspection was taking place. I began as a habit now to bring 4 of those plastic sign boards with me and offer protection by placing one on the ground, then my first medium which is promptly covered with a sign board. So is the open hive top. This gives me time. I can decide to inspect either. Bees are contained, not flying at me, and everyone is safe always. I can pry off the next box and set it on the sign board thats on the first box, then cover it with another. It works so well, why have I never heard of anyone else doing it?
Only my 2nd year… Lisa
Many people use pieces of canvas to lay over the open boxes. I’ve heard them called inspection clothes, manipulations clothes, draw quilts, and other names. I use screened inner covers or just pieces of cardboard. They all do the same thing.
Rusty, Thank you for the link. They are nice robbing screens. I will order a dozen of them to try out. Covering boxes as they are removed is an excellent idea I have used for years now. It sure keeps down on the bees flying around and it keeps them much calmer. This is a great post with some great ideas. Thanks again !
Another thing I like about this screen is the bees cannot ‘see’ through the front …. and it only has two entrances on the top. An improvement over the wooden/mesh screens. I like ! Thanks !
I am in a predicament. Due to our severely dry summer (wildfires and high temps) I began feeding bees. Robber screen is in place yet I thing they are still being robbed. Entrance is reduced to one small 1.5″ opening and my own bees I think have backing up traffic coming and going. Front of screen, I believe, is covered with robbers altho they won’t tell me they’re robbing. There are fights. Should I stop feeding 2:1 syrup in upper most super that surrounds the feeder? I don’t have a second upper entrance because of robbing. Would it do any good to cover the screen where the small entrance is visible? What makes the robbers leave? Do they smell the sugar formula on my bees? Any comments and suggestions gratefully appreciated.
Are you sure it is robbing and not drone eviction? If you’ve reduced the entrance and are using robbing screens, there isn’t much more you can do. Don’t use any essential oils in your syrup, though. That would make it worse.
I am in eastern south dakota and my buuy has his bees about 75 yards from my four colonies. I had 4 medium supers on two of these colonies. The supers being older had a few openings on corners etc. Today the bees from his Warre hives were robbing mine. I don’t know when it began but it was in full swing. I duct taped all possible entry points. I had planned to put escape boards on to remove in morning but hesistated now. What should I do? I ordered four beesmart robber screens. Should I go ahead this eve and place the escape boards and reseal for the night? I thought to remove two supers at at a time, or should I go for all four on each now? Or should I wait leave them sealed up for a week until robber screens get here? I would like to start feeding 1:1 syrup with fumidil soon. Thanks Rusty!
There is no perfect answer. If it were me, I think I would go ahead and try to remove all four supers at once. It might take them longer to empty out, depending on how many bees are hanging around up here. But every time you reopen the hive is like reopening an old wound. Certainly you won’t start robbing by putting in the escape boards because it’s already started. So I would just go ahead and do it in the evening when the robbing slows down.
Just be really sure everything is sealed or the robbers will get in the supers and with nobody to defend, the supers could get emptied out in a jiffy. Maybe there’s a better way, but that’s my gut feeling about it.
Today was 86. Tomorrow 65 for high and 40 low. Same again tuesday. Then a steady rise into mid 70’s rest of week. So do you think I should try pulling the supers on the next couple days? Then install robber screens?
Okay, I didn’t see this comment before I answered the last one. (I see them in reverse order, which is weird sometimes.) Anyway, yes. Temperatures of 65/40 are good to work with, and with 40 at night, the supers may empty over one night. So yes, get the supers off before it gets warm again, and then install the robbing screens as soon as you get them. That way, you can get on with your syrup, etc without waiting.
Ah yes thanks! This makes sense. To be honest I have not ever used robber screens in over 20 years of beekeeping?
P.S hope there is some honey left ?
You probably didn’t have your friend’s warre bees chompin’ at the bit, either!
Yeah that is true. He was worried they would not compete with Langstroth hives which were overwintered large colonies. One a survivor queen from Old Sol in Medford OR. But I did ask that he maybe relocate them for a little while to allow mine to bounce back. Heading out in cool morning to place the escape boards. Wednesday morning 40f.
So truth be told upon investigation this evening I opened the hive that seemed more troubled with robbing. About half the honey in the supers. I dug down into the brood boxes…cleaned out. The bottom box had about 8 or 9 queen cells some capped some open. No bees except robbers. That was a really strong hive with no indication of swarming at least 3 weeks ago. Well I added hopguard strips for varroa control two weeks ago. This was the survivor hive with the survivor queen. Gee, wonder what happened this late in the season. The robbers were cleaning up the mess. Wow. What’s your take?
Wow. That is so sad. But I know robbers can make quick work of honey stores, so it doesn’t surprise me. Other than that, it’s impossible from here to know what happened. It’s possible robbers killed the queen, but it sounds like maybe she was weak for some other reason. I never had an issue with queens and HopGuard, so I doubt it’s that. Did you notice a lot of mite drop from the treatment? Maybe there was a high virus load in the hive.
Actually I had not noted the mite count. I was about to place a screened dadant bottom board on tbis one. The bottom board was littered with wax cappings with moth larvae wriggling. There seemed to be many bees in this hive. I actually made a split from it which is going great guns with a new queen this early summer. In fact the other over wintered colony is good too. I am down to four now. One tbought was CCD? The fact there was no virgin or mated queen with even a small cluster made me wonder…
Not CCD, I don’t think. That seems to be pretty much a thing of the past. See, “The demise of colony collapse disorder.”
Thanks! So, maybe tomorrow morning early when it is cool install boards and remove boards and supers when it is a lot cooler on tuesday morning @ 7am?
That sounds good, but check to make sure the supers are fairly empty. Sometimes when I put escape boards under multiple supers, I have to wait ttwo days.
I like the recommended robber device but this company’s shipping is outrageous…hopefully that will change in future….I don’t mind paying a fair price but almost $19 to ship 2 is a rip off.
Thanks. I didn’t realize the shipping was so high. I think all companies need to take a serious like at pricing. When shipping is more than the product, something is wrong. I often skip orders because of that.
Anyone got a 100% product that eliminates odor of butyric acid, i.e BeeGone? I had about a pint of it spill in a wooden cabinet and whole garage reeks to high heaven..? thanks!
Ewww. That sounds bad. Anyone have an idea?
Another benefit of robber screens in the southern US is it helps keep usurpation swarms from gaining access. I removed two in one day from the same hive and a total of four in just one month. I think I missed one because I found a new unmarked queen in another hive. Guess I’ll find out come spring if they’re Africanized. :-/ My project for this morning is to build robber screens for the rest of my hives since it’s clearly usurpation season.
I didn’t realize usurpation had a season, but now that I think about it, it makes perfect sense. Why go to all the work of putting away winter stores when you can just steal them? I agree, that’s an excellent use of robbing screens in AHB areas.
In truth, I have in years past seen them in late spring and all through summer, but this year they waited until the cool weather of fall to descend, bang, bang, bang. I was sitting in the bee yard a couple of days ago when the last one descended with a loud buzzing, which was interesting to watch but also sent me into panic mode for gathering supplies to remove them.
Hi Rusty, I’m a seventh year beekeeper here in W Oregon, and this year and last we have had extremely late frosts (mid-December). Because my hives were absolutely overrun (and subsequently decimated) last year with yellow jackets until then, I put on robber screens early this year and was about to take them off today (12/13) after at least 4 days of frosty nights, and then just saw a yellow jacket on a landing board! So I left them on. My question is: do I need to put mouse screening over the top of the robber screens, or will a robber screen keep mice out? They are your standard little 4-piece homemade wooden screens, with the opening across the entire width of the box.
I’m sure a mouse would climb right over a robbing screen. Can you fit the mouse guards under the screen? Or maybe you will finally get a freeze. We got our first one this week. Good riddance yellowjackets.
Thanks very much for the quick reply. I will just cut the mouse guards back a little and push them into the top opening of the screens instead of the actual entrance below. ? I don’t think it’s getting any colder for awhile yet.
I’ve moved some hives before less than the usually stated 2 miles and left a few leafy branches in front of the hive entrance for a week to force the bees to re-orient to the new location when leaving the hive the first few times. Do you think a robbing screen would serve the same purpose?
I don’t know for sure, but I don’t think it would force re-orientation. I assume that once they get outside the hive, they will recognize their surroundings.
Hi Rusty, I got the Blue Sky robber screen, and tried to install it last night. But my slatted rack extends beyond the base of the brood box by about an inch, and makes it like a couple of arms on each side that extend out and kind of make a porch. So the box isn’t flush with the rack.
I tried sliding the box forward so it sits flush, but that left an opening all along the back of the hive. I’m stumped. Maybe your slatted rack is the same size as your brood box? Or will I need to break off the tab to make it fit and then fill in the gap with something?
Two steps forward, three steps back. Oy vey!
Hi again, I posted a question about the box not sitting flush with the slatted rack. But I figured it out.
I took the hive apart and remembered I have a screen in there as well. That was what was sticking out.
So I slid it back a little, now everything is flush in the front, and I can attach screens tonight.
Thanks for your help! Now, can you help me with my router? Ha!
Good that you found the problem. Little things like that can cause big aggravation.
For colonies that haven’t had a robbing screen on all spring, I’ve found the need to install the solid cover over the screened bottom board prior to attaching the robbing screens. Otherwise, many bees cluster under the hive, clinging to the screen until they die. They just don’t seem to try another route after finding their way down there.
Thanks for all you do, Rusty!
How timely. I read this just before I installed my robbing screens yesterday. I took your advice and had the fastest re-orientation to the robbing screen entrances that I’ve ever seen. Good to know! And thank you.
Hi Rusty, when you put the robber screen on a new nuc, one that is making their own queen, is it your experience that the robber screen does not cause an issue with the queen making her mating flights? I’m wondering if I should remove the screen during the period of time when she likely will be taking her flights?
Since the queen never left the hive before, she won’t have anything to compare to, so she should be fine. The robbing screens can be confusing to workers because most of them already learned another way in and out. A virgin queen knows no other way in and out, so she won’t be confused.
Hi there, I’m a first time beekeeper this year in the northeast with 1 hive. I made a robbing screen with wood and screen with an opening at the top about 3″wide and 1/2″ deep. I removed the entrance reducer before placing it last night. I’m wondering how long it usually takes for the bees to adjust to the new entrance. I’ve been watching them and there is lots of crowding at the front, bees coming back with pollen and don’t know where to go, and a cluster of bees under the screened bottom board. I feel terrible watching them and feel like I’m setting them back from making honey, etc. I just want to run outside and remove the robbing screen! But I have noticed some bald-faced hornets and yellow jackets in my yard. Since I’m new, I just want to make sure this is normal behavior when you place a robbing screen.
Yes, it is perfectly normal. It usually takes a few days for the bees to sort it out, but some may take even longer. To reduce clustering under the screened bottom board, put the sliding varroa tray in for a few days.
You have helped me no end over my first years of beekeeping, which I love.
Good or bad thing, I set up a bait hive near to my apiary. A great number of bees were going in and out. I started to feed them, each day the syrup had all gone. I did my first inspection of this new colony, only to find no bees. You know what I am going to say, my other hives must have been just helping themselves. I had screens on all my other hives, so they must have thought it was their lucky days. Is this a bad thing?
No, it’s not really a bad thing. It’s like open feeding. The bees found a source of food and they scarfed it down. But it must feel disappointing in a way.
If a bait hive is being constantly robbed by other colonies because it’s a food source, a swarm wouldn’t see it as an attractive potential home. Just put some frames with old, empty brood comb in a used brood box. Tack a piece of ply on the bottom, drill a 3/4″ hole in the front, cover the top with something easy to remove, and hang it several feet off the ground in the tree-line or other shady spot. Attaching a board vertically on the back with hole(s) makes it easier to hang up on a tree, etc. You can put one of the proprietary swarm lure products inside or perhaps a few drops of lemongrass oil, to make it even more evident to swarm scouts. Nice thing about bait hives for swarms of the sort described above is that you don’t have to be in a huge rush to recover them. I like to let them set up their broodnest for a few days. Then I close up the entrance after dark or early in the morning, take it down and hive them at a distant location. If you don’t have a distant location, there are other strategies to get them reoriented, and since the queen has started a broodnest the whole swarm is very unlikely to abscond when you move them. BTW, it’s a great idea to have some bait hives out during swarm season, if for no other reason than to catch your own.
Hi Rusty –
So here in the mid-Atlantic it looks like we might finally be hitting the start of spring, and my colony came through the winter nice and strong. I’ll definitely be taking out the entrance reducer, but should I go ahead and remove the robber screen during the honeyflow? My thought is that from what I read, there’s little chance of robbing this time of year (at least until harvest) and screen removal would make it easier on the bees for approach and landing. I’m also going to be trying an upper entrance on a shim above the honey super… after the honey flow is over do you think I should I leave the upper entrance open through the year (with its own robber screen of course) or close it up? Thanks!
Yes, it’s probably best to remove the robbing screen before nectar flow, just to lesson congestion. I like to leave an upper entrance in place during the heat of the summer, but if robbing is a problem, you can screen it or remove it and use a screened inner cover.
Hi Rusty – I have two hives. I started with an Italian package in early April, then added a Carniolan nuc nearby in early May. It’s hard to know if what I witness is the difference between a package and a nuc or the difference in bee breed. Yesterday, there was a crazy amount of noise and activity in front of the Carnie hive, with some Italians trying to get in at the seams. I didn’t see much fighting. Mostly it looked as if the Carnies were being super industrious carrying in pollen and the Italians were either drifting in or looking for a way in. It is possible that I was mostly seeing an Carnie orienteering flight. (The Italians at the seams were super obvious.) I came to your site and managed to borrow a Bee Smart robbing screen last night. I live in California, where we’ve just squeaked out of major drought, pollen is high. I’ve had problems with lizards living in my hive and even eating the brood out of the comb. Right now I have a mouse guard over the Italian entrance (to keep out lizards) and the robbing screen over the Carnie hive. I am wondering if I can use robbing screens on both hives year round to protect the hives from lizards, yellow jackets (we are inundated with aggressive yellow jackets) and robbing. I’m using a slatted rack between the entrance board and brood box and am wondering if I should also try screened inner covers. Past beekeeping failures have been due to swarming, drought, heat and pests.
I use robbing screens year-round. I see no reason not to, especially if you have lots of bee pests.
I have my first hive this year – a horizontal Langstroth. I’m hoping for some input on the robbing screens.
I’ll be leaving for a vacation during the first week of September and wonder if I should install a robbing screen just in case there are any issues while I’m gone. What do you think?
I’m also wondering if the screen that you recommend would work on the flat wall of the hive. I’m using a single slit opening that is about 5.75″ long but it is reduced to a very small entrance. I have plenty of flat wall length to place it against, but if there is anything that needs to fit into the opening rather than flat frame, it wouldn’t work. I looked at the photos, but they don’t show the side that goes against the hive.
Thanks for any input!
I appeared to have a robbing situation beginning, so I put your recommended screen on the front of my two hives. I did this during mid-day since it appeared bees from another hive were trying to gain access and there was some fighting on the front of the hive. Bees have now crowded all over one of my hives, and I’m trying to determine what I should do next. I was given advice to pull the honey and to consider moving the hives 5 miles away if it truly is robbing. I have a commercial bee farmer very close, so there are a lot of bees in the area.
When pulling honey, it did not appear like any robbing was going on inside the hive. May I send you a couple of extremely short videos to show you and to get your opinion? Here is some additional info. Both of my hives are first year and started as nucs. One hive has exploded in population, so I added a third hive body a month ago.
The hive has a lot of brood and all frames full with brood and honey, so I took a couple of frames of brood out and placed them in my other hive that is not as strong. I replaced them with empty frames. The strong hive had some queen cups at the bottom of a frame in the second brood box, and I scraped them off. I’m struggling with what to do next. Thoughts?
Are you sure you are seeing robbing and not bearding?
I have a couple of questions that I’m hoping you can comment on regarding robbing screens.
I put on a robbing screen a few weeks ago as a preventative action. This hive is a horizontal Langstroth, so it is a home made screen constructed to work with this particular hive. It has one opening slot at the top. (I would like to post a photo, but I haven’t figured out if that’s possible in the comments…) It will also be helpful to know that I only have one entrance which is reduced to about 1″-1.5″ at all times. This has worked great for the hive.
1. It seems hard for the bees to carry out the dead as they have to haul everything up and out. Should I be concerned with this?
2. My inclination is to just leave the screen on year-round.
A. Will that be an issue in the spring when they need to clean the hive out?
B. Will it be an issue in the spring when there will be lots of traffic and bees coming and going during heavy flow?
Otherwise, do you think there is any issue leaving it on year-round?
And….I wanted to thank you for a great site! This is literally the first place I look for information and I always enjoy reading your articles.
First, to post a photo you have to email it to me: email@example.com
Now the questions.
1. It might be harder, but they manage just fine.
2. I’ve left my robber screens on for years. I take them off and clean them each spring, then they go right back on. If it’s an issue in spring, I’ve never noticed it. Sometimes bees get backed up at the entrance during honey flow, but a small entrance doesn’t seem to inhibit honey production. All their attention can go to nectar collection instead of guarding the door and dealing with robbers and wasps.
Thank you for your reply!
I just emailed 5 photos to you showing the robbing screen and the horizontal hive. I’m also posting the questions here.
1. Do you think my screen is too tall?
This screen is about 7.75″ tall. I’m wondering if it should be shorter. I often see bees trying to carry dead all the way up to the top. They climb on the screen to go up, then when they reach the wood at top (still inside the screen), often fall back down to the bottom. I even see some bees NOT carrying anything climb up the screen then fall back to the bottom.
We just replaced the screen in the frame today as there was a small hole in it. When we did that, we also scored the interior top and sides with a tool to make it “rougher” than the smooth wood to see if that helps them cling to the to interior better. (You can see this in the photo: 5 – scored interior top closeup.jpg)
This leads to my second question:
What about open top robbing screens?
I’ve seen the robbing screens that have no wood piece across the top. It is totally open on top. (See: http://entomology.ucdavis.edu/files/147611.pdf ) I also notice the height on it is 4″ which is about half the height of mine.
Obviously the home bees would be able to get out of that screen much easier. But what about incoming robbers? Seems like it would be much easier for them to get in that kind of screen? The writer also stated that he wasn’t sure if it would work for yellow jackets which is very important!!!
I’d love to hear your thoughts.
I don’t know if there is a maximum height for robbing screens or even a recommended height. I use commercially made ones and they are just under four inches high and they work great, keeping out both bees and wasps.
Many people tell me that the open-topped ones work fine as well. The reason they work is because robbers are following the scent, not the sight, so they keep trying to get in where the scent is coming from. They never bother to go up away from the entrance because the scent isn’t coming from there. It seems improbable I agree, but we’re thinking about it from a human perspective, not an insect’s perspective.
For this season, I would just stay with the screen you’re using. Then, when you have time, you can cut it down if you want to make an easier carry-path for your bees.
I just came out of a major robbing situation. Unfortunately, as a newbie, I made the mistake of thinking things were going great. Lots of activity! I had a peek in my hive one day, literally cracked the lid and peeked in at the honey super and noticed that some of the comb which had been previously drawn out, wasn’t even drawn out anymore. Ignorantly, I figured the bees knew what they were doing (DUH!) and left them to their work. Getting on into fall though I figured I’d feed them some syrup from the hive top feeder and see if they’d take that. WOW! Did they! I would put in a 2:1 syrup made from 10 cups of sugar and by the next day it was done and each time I replaced it the next morning it was gone and I could see little bee tongues licking from under the metal cap. But it just seemed too much. By now this had been going on for a few weeks. (Ugh, I know! I know! What was I thinking?) So I started looking into robbing as a possibility. What harm would it do if I put on a robbing screen? So I just fashioned a basic screen tunnel that I tacked on and waited. Sure enough all the activity that had been going on everyday slowed to a trickle. My bees were still coming and going having figured out the screen but it was a mere fraction of the activity that had been happening. Now, believing it had indeed been a robbing situation I checked the syrup and it was of course full. I started to imagine the damage that had occurred during the weeks of robbing. Weather has not been great here, either quite cold or just dreary, rainy days. I finally made a decision that I had to get in the hive to see what was going on. Is there anything left? Is there a queen? What kind of numbers were left? I don’t know how but when I opened my hive today business was booming. Lots of bees, lots of honey. I can only guess at why there wasn’t complete devastation after robbing going on for so long. All I can think is that with so much syrup available at easy access that the robbers went straight for that and my hive was happy to share as long as their stores were left alone. Thank you Rusty to the wealth of information on this site and your replies to each question. Thanks also to the many beekeepers who ask their questions given that each situation is a little bit different than the last. It is confusing, conflicting and helpful all at the same time. 🙂
Many of us, as newbees, have seen that burst of activity and thought it was a good thing. It can be extremely confusing, for sure. Happy to hear it all worked out!
I was planning on building a robber screen for my top bar hive but I run into a design problem due to the sloping sides and my horizontal landing board. As a result, I don’t think I can build a robber screen that has a top escape.
Does it matter which side has the escape for the bees? Could I build an escape on the sides assuming it is several inches horizontal distance from the actual hive entrance and not too large? Perhaps 4″ distant on each side from the actual entrance? Alternatively, will bees use a bottom escape?
I don’t think it matters too much. The main thing is the escape entrance should be removed from the real entrance. Robbers navigate by smell, so they will keep attempting entrance at the real entrance where the smell is coming out.
A couple of questions. Do the robbing screens not protect against mice? I guess I thought that they would do both. Also, Can you leave them on year-round or do you always take them off in the winter and add mouse guards? Thank you so much for being here. 🙂
It depends on how the robbing screens are designed. Some will keep out mice and some will not.
I leave my robbing screens in place all year and, so far, they’ve kept out the mice. Mine have two entrances for the bees, so in string and summer I leave both open, but in fall and winter, I close one.
Hi Rusty, I am overwintering for the first year with robbing screens installed. I have noticed that they are not removing dead bees through the top of the robbing screen, and they are accumulating around the base/entrance, on the interior of the screen. Do you just clear them out from time to time? My screens have a 3rd lower entrance that I have kept closed to prevent robbing/mice, but wonder if I should open so they can clear out dead bees easier? I am near Sacramento, they can be pretty active during the winter…
You can just take the screens off and clean behind them. Also, if not many bees or wasps are flying, you can open up the extra entrance, at least for now.
Can you use robber screens (Beesmart) and entrance reducers for overwintering or would that be too much?
I leave my Beesmart robber screens on year-round.
Hi Rusty – I’ve used the BeeSmart robbing screens for a few years, and generally like them a lot – they do seem to be very effective for preventing robbing from getting started. But after a few years, my bees have almost completely propolized the vented area in the screen, drastically reducing the opportunity for airflow through the screen. Have you encountered this with yours, and how have you handled it? I run between 25-40 hives depending on pollination needs on area farms, and am reluctant to sit and individually clean out each hole in each screen. Any suggestions? Thanks so much for your helpful site.
So far, I’ve cleaned them individually during the winter, but I’m sure there must be a better way.
Rusty, I used to use the fancy robbing screens that you see in bee catalogs but for the past three years I’ve just been stapling hardware cloth to the entrance and it has been working well. I haven’t had any robbing even with feeding very weak two-frame splits during a dearth (with essential oils). And it’s a lot cheaper.
I made a short video on this which I would love to have your opinion on if you ever had time, I had a lot of fun making it: https://www.youtube.com/watch?v=x2a6NVvLc5A
Yes, that will work just fine.
Rusty: I’m curious why the pictured hive is strapped. Is there a reason other than it had been or was going to be moved? Thanks. Alan.
I strap them to keep the raccoons from knocking off a box or two. Works great for raccoons, not so great for bears.
My question about robber screens is if I use them on all 20 hives in the apiary… won’t any drifting or robber bees have learnt how to enter since their own hive has the same robbing screen?
Just trying to think it all through before purchasing any.
Thanks in advance
This doesn’t seem to be a problem. Bees don’t see the way we do. When they go to rob a hive, they follow the scent, not the hive design. They don’t learn the geometry of the opening the way we would. Instead, they just keep sniffing in search of the opening. The holes allow the scent to leave the hive in multiple places, not just the entrance, which is highly confusing to the robbers.