Problems in Dubia roach breeding colonies are common, but bad outcomes are rarely inevitable. For most of the common issues at-home Dubia breeders face with their roaches, there are usually easy fixes.
In fact, there are simple solutions to almost all Dubia roach breeding problems, whether common or not. Successfully raising healthy and productive Dubia roaches is largely a matter of preventing small problems from occurring, identifying and fixing problems that do occur, and always acting quickly.
You can skip straight to troubleshooting by selecting a problem category link from the list below. The next few paragraphs are introductory and provide background information.
- Roaches not breeding
- Roaches breeding slowly
- High adult mortality
- High adult male mortality
- Slow colony or nymph growth
This guide describes how to identify, fix, and – as much as possible – prevent problems in Dubia roach breeding colonies. It is based on the entirety of our breeding experience with respect to hurdles and roadblocks, and we earned most of our knowledge the hard way.
In the beginning, we searched everywhere for Dubia roach breeding information. We looked online, at our public library, and at our local university library. We gathered and studied all the literature we could find. But practical information was hard to come by. We spent a lot of time piecing together fragments of data from lots of sources before we had anything we could put to use, and even then it took actual experience before we knew what to make of most of it. What we really needed back then was a single source of information that we could reference when we needed. Something like, say, this troubleshooting guide.
So just because we learned the hard way doesn’t mean everyone has to. Before we begin though, it’s important to frame the issue.
Big problems occur in Dubia roach breeding colonies, but they are not the norm. Small ones are. However, small problems have a habit of becoming big ones if you don’t deal with them quickly and correctly. The first lesson is that you must deal with small problems as they arise. It is unwise to let them fester. Speed is essential for easy fixes with minimal damage. Avoid procrastination. When you procrastinate, small, common problems may become big, unruly ones.
We’ve been breeding Dubia roaches for a while, and we’re still learning what we can get away with, so to speak, and what we can’t. Tropical insects are delicate. They have very specific requirements that we have to work hard to meet in North America. And it isn’t always possible to meet them all. Food, temperature, light cycles, humidity, air circulation, population – these are all factors that largely regulate themselves in the wild. In captivity, however, the roaches rely on us to provide these things for them. When one or more are not to their liking, they can neither escape nor complain. They just react.
The bottom line is that until you have a good sense of what’s going on with your roaches, always address problems with urgency. Don’t put off until tomorrow what you can do today. When you get a good amount of experience, you’ll have a sense of what you can and can’t put off until tomorrow…but you’ll probably not want to because you’ll know firsthand how dangerous that can be.
If you need reasons why this is true, consider that it’s wet, warm, and dark inside your colony. This is ideal for the rapid growth of bacteria and mold. Also consider that there is often a huge difference between the environment inside the enclosure and what exists outside of it in the average American home. Throw in the fact that B. dubia is a sensitive tropical insect that responds unfavorably to the wrong conditions, and you can see why problems are common, how they can get out of control quickly, and that it is wise to act fast.
Also consider that while a few dead roaches here and there rarely cause problems, a large number of deaths all at once will get nasty in a hurry. When roaches die, others in the colony may eat them. If a problem in a colony is serious enough to kill roaches, the last thing you want the live ones to do is eat the dead victims and then sit around in a hot, dark, wet environment. Throw on top of that the fact that dead roaches may secrete a chemical that repels the live ones so strongly that they may become sick if they can’t escape, and you can begin to see how procrastination seldom makes things better and almost always makes them worse.
So with this in mind, let’s move on to the breeding problems and their solutions.
1. Roaches not breeding
As certain as death and taxes, insects reproduce when conditions support it. That’s not only how they exist, but arguably why they exist. They surely would not exist if they failed to breed. If you think your Dubia roaches aren’t breeding at their full potential, the first (and often only) place to look is their environment.
No breeding activity at all is cause for immediate concern. If this is the case, something is seriously wrong in the colony. However, before panicking, allow us to suggest that it may take more time to see results from mating than you think, and there might be nothing wrong with your roaches or your colony. Here’s why:
The Dubia roach reproductive cycle
Female Dubia roaches mate around five days after adult emergence, but it takes another 65 days before she will give birth to nymphs. This is what you can expect from new females under no stress when they start breeding immediately upon introduction to males. However, the time it takes to see babies can be even longer if the females were stressed at any time, so factor this in. If on the other hand you started your colony with existing female breeders, you may see babies immediately, but it could also take up to 65 days. The chance that it would take this long are slim, but it is within the realm of possibility. When you end up with babies depends entirely on where you started.
If you rule out the timing of B. dubia’s breeding cycle and you’ve determined that there is a problem, the next thing is to recognize that whatever that problem may be, it’s one part of a continuum with optimum breeding on one side and no breeding on the other. The key is that something happened, and keeping that in mind will help you fix the problem. So will the following:
2. Roaches breeding slowly
Dubia roaches breed better in some conditions than others. The goal is to know these conditions, then provide them to your roaches. The following is a list of the most common reasons Dubia roach reproduction slows, and how to fix it.
Dubia roach reproduction slows as enclosure temperatures move away from the “sweet spot”, which is between 80ºF to 90ºF. This is the range we recommend, and it’s based on a little scientific research and a lot of observation. Unfortunately there aren’t any studies on ideal Blaptica dubia breeding temperatures, so we start with what exists then work on experience from there.
If colony temperatures are consistently high, or if they rise above the sweet spot for too long, production slows. If you experience this, the solution is lowering the temperature. Keep it in the sweet spot as long and often as possible. If it wanders, find the cause and fix it quickly. A breeding colony can handle some temperature fluctuation, but less is better. Dubia roaches can become stressed when temperatures are less than ideal, and as you know by now, stress is bad.
When colony temperature is consistently low, production will decrease. Unlike the production slowdown seen with high temperatures, which is a general decline in the rate of production among the roaches that make up the colony, individual roach production will slow when temperatures are too low. This means the roaches will reproduce not just less frequently, but they will also give birth to fewer nymphs.
When diagnosing thermal issues, first be sure to find the colony’s actual temperature, which is different from the temperature you’re almost sure it is. Get a “high” temp reading by measuring with a reliable thermometer at the hottest time of the day. Then check it again when the heat source kicks off. If you use heat mats under your bin, check temperatures a few minutes after the thermostat clicks off. Heat under a plastic bin dissipates more slowly than it accumulates, so if your heat cycles on and off rapidly as temps rise and then fall, the colony may be getting hotter than your thermostat’s setting, and hotter than your thermometer indicates.
Next, find the low temperature the same way you found the high. Check at night or when the temperature in the storage area is at its lowest. To capture the actual low, try to get a reading just before the heat source kicks in.
Then, make whatever changes are needed to maintain a consistent temperature between 80ºF and 90ºF.
NOTE: a nighttime drop in temperature is OK, and it may reduce your electricity bill with no impact on production. However, the drop should be no more than about five to ten degrees. A small nighttime temperature drop combined with at least 10 to 12 hours of temperatures in the middle of the sweet zone should result in good production numbers.
Reproduction may slow if Dubia roaches don’t have enough food or if they have the wrong food. Too much protein and too few carbohydrates will have a negative effect on their health. So will too many carbohydrates and too little protein. Too little dietary protein may result in the adults eating their offspring. Larger nymphs may also eat smaller ones, which obviously has a negative impact on production. Check their diet for balance while keeping the following questions in mind:
- Are you giving them a high quality protein source?
- ARE you giving them a high quality carbohydrate source?
- Do you feed them fruits and vegetables?
- How often do they go without food, and for how long?
- Do they ever go wild when you feed them a certain food? If so, is there any chance there’s some nutrient in that food they may be deficient in?
Dubia roach diet and nutrition is a complex topic and one we’ve studied in great depth. The average home breeder can successfully breed Dubia roaches if, among other things, he or she supplies adequate nutrition. If you’re in doubt you can try our roach chow and see if it makes a difference. How much improvement you’ll see depends on how bad off your roaches are now and how big (or small) your colony is, but if you have a sense that there’s a problem somewhere and a change their diet to something you know works ends up fixing it, then the problem is identified and a solution is in sight. If not, the issue may be related to something other than diet.
Tropical roaches require adequate humidity for reproduction, and low humidity can cause a reduction in productivity. Dubia roaches use humidity to keep their egg sacs, or ootheca, moist. You will notice that at times, they will climb to the highest location within the colony and extend their egg sacks outside their body. This helps prevent the ootheca from drying out. Dubia roaches are somewhat unique in this way. They are among the few roach species that carry their eggs internally. However, they still need medium to medium-high air humidity to avoid problems with their egg sacks.
To avoid these problems, use a hygrometer and maintain colony humidity at 40% or higher. 40% is the bare minimum. We haven’t done much testing in this area so we can’t say for sure, but there seems to be a natural cut-off around 40%. To be safe, you might consider shooting for 60% humidity and boosting with manual misting, an occasional bowl of hot water nearby, or even a humidifier when it drops to 50%. Use whatever method works for your situation. Humidity is more likely to remain in the target zone if you use a narrower range than you know they need. Dubia roaches are OK with high humidity. There is no consequence to overshooting the humidity target. The only thing you need to worry about is humidity falling too low.
Too many males
Dubia roach males have a tendency to eat young nymphs when colony stress and competition for mates is high. This is one of the reasons we suggest in our breeding guide to keep the female to male ratio between 3:1 and 7:1. Your breeding colony contains captive roaches that can’t escape colony problems, and males can stress an entire colony with their aggression. Of course, stress can also reduce productivity. Avoid it when you can.
The solution is to count the adults and bring the ratio of females to males within range.
To one degree or another, these are the sources of the most typical Dubia roach breeding problems. Most of these problems will clear up – or you can avoid them completely – when you get food, temperature, humidity, and colony social order under control. Of course, it’s not always this simple. There are a smaller subset of “non-typical” problems with different origins not related to the more broadly defined causes listed above. If you’ve tried everything mentioned so far and nothing is working, or if you want to further reduce problems or the potential for problems going forward, the following are other factors you can consider:
Dubia roach colonies should not smell bad. They tend to have a faintly musty smell, but it’s neither “bad” nor “strong”. Unusual or unusually strong odors likely indicate mold or some other type of growth in the colony, and this may cause breeding issues. If you sense any unusual odors, consider identifying the cause, cleaning the bin, and preventing it from happening again. Maintaining clean enclosures is generally good practice anyway, and it can’t hurt to get into the habit if you aren’t already.
It’s important to note that “clean” does not mean free of debris. It doesn’t even mean free of the occasional smell of dead roaches. Some of this is normal and you should expect it. In fact, Dubia roaches benefit from frass. It doesn’t smell bad, and frass itself won’t cause mold. It’s also inevitable, and it’s a necessary part of roach life. Consider frass an asset. Nymphs need it to survive and roaches of all ages seem to enjoy burying themselves in it. Frass is good. Too much frass, however, may cause problems.
We think the way to deal with frass is to clean the colony and remove dead roaches and excess frass, but leave some of the frass behind. A good target is enough frass to cover the enclosure’s floor but not enough to create any substantial depth. More is probably OK, but it’s not necessary, and it could contribute to problems. The deeper the frass, the more water it holds. At some point, moisture will accumulate faster than it evaporates. This is something you should avoid because it will lead to mold.
Too much light or other disturbance of their colonies can have negative health effects on your roaches. Aim for providing no more than 12 hours of light per day, and keep your roaches away from visual and auditory disturbance as much as possible. Don’t shuffle things around in their bin more than once a day. Less is probably better if you can. The ideal amount of disturbance would be none, but that’s not possible or practical. Just keep disturbances to a minimum. Don’t avoid necessary cleaning chores for fear of disturbing the roaches. Use your judgment. Do what you need to do keeping in mind that less is better.
NOTE: As mentioned, it’s critical to buy healthy Dubia roaches for your breeding project. Unhealthy roaches can languish for weeks and months, never recovering from their prior life challenges (external link). We’ve seen this all too often. In the beginning, we bought roaches that were so bad off that we removed them from our breeding stock altogether. In our opinion there’s no substitute for optimum conditions not just from the day each individual roach is born but from the day it’s parents are born. Healthy breeders have healthy offspring, and they carry that advantage throughout their entire lives. And the advantage is a big one.
That said, Dubia roaches that are unhealthy or struggling or stressed or in decline due to old age will not reproduce as quickly or robustly as those without health issues. Where lower productivity is an issue and you can’t find the direct cause, do everything you can to improve the health of your roaches and your colony. This may increase their productivity or even eliminate the problem altogether, depending on the cause.
3. High adult mortality
If you notice that your adults start dying at higher rates, there are a few things you can check.
With any sudden mass die-off in a roach colony, the first suspect is disease. If you think this is the case, do the following:
- Remove and properly discard the dead roaches.
- Remove and separate the remaining adults and nymphs.
- Discard the contents of the bin, clean it thoroughly, then set it aside to dry.
- Set up the separated adults and nymphs in new bins with new food, water, and harborage.
- Feed them only dry food for a week or two and keep humidity at it 40%.
- Check the bins at least daily and remove any roaches that die.
- Wait. If a week goes by and everything looks OK, you can recombine the adults and nymphs and continue on as you were.
- If things get worse, at least you will have a better idea of the problem’s cause.
Pesticides and other chemicals
We hate to admit it, but this happened to us in the past. We had an unexplained die-off that we later determined originated from high pesticide produce. That’s when we learned to always wash fruits and vegetables before feeding them to our Dubia roaches. A tiny amount of bug spray like Raid Ant and Roach Killer can kill roaches by contact even weeks and months later. Pesticides don’t mess around. As they say, pesticides “kill bugs dead”. Take every precaution to keep them away from your roaches.
With any sudden die-off, also consider food as a potential source. If you noticed that it happened three hours after you dropped an unwashed Mango from South America into the colony, then you probably have your answer. Follow the same steps listed under Diseases above, except there’s no need to separate adults from nymphs. With a little luck the situation will resolve without too much loss.
Something as simple as old age can cause falling production in Dubia roaches. If you buy a bunch of new adult females as breeders, for example, mate them with a group of males, then remove the offspring before they mature, you will end up with a group of old females that reach old age at the same time. Keep this in mind, and always let at least some of the nymphs grow out into breeding adults. If you don’t, your breeding operation will be unsustainable. If you don’t do this consistently, roach productivity will rise and fall over time, and there may even be large gaps in production. When you see new nymphs, you can feed some of them off to your animals, but set some aside and let them grow.
Studies suggest the stress of breeding reduces longevity in roaches, but there’s no avoiding this in a breeding colony. You can, however, reduce overall stress by finding other sources of stress that you can control. Overcrowding, too much protein, too few carbohydrates, too many males, too much light, wrong temperatures, and all the other conditions mentioned throughout this page and our breeding guide can each cause stress. They can also almost always be fixed or at least mitigated.
Do a mental inventory and see if you can think of anything that might be causing stress. If you come up with something, fix it the best you can and see what happens. You may also consider changing up their diet to see if that helps. If you need more information on this topic, consider reading our article about Dubia roach die off. It covers the mortality issue in greater detail from a slightly different perspective, but one that is relevant to a breeding colony.
4. High adult male mortality
This problem sounds a lot like the previous one, but unless it’s caused by one of the issues listed above, it’s not. Male Dubia roaches are more fragile than females, and they don’t live as long in breeding situations. You may need to adjust for this.
Lifespan difference between sexes
After a while, you may notice that the males in your breeding colony die sooner than the females. Because it would be very unusual for females and males to not be equally affected by something within a colony serious enough to kill them, consider that the cause might be just be the natural life-cycle of the roach. Female Dubia roaches typically live between 18 and 24 months. Males live between 12 and 18 months. Males naturally die sooner than females, and until a colony is self-sustaining, it may be necessary to replace some males along the way.
The good news is that while the issue is common, most people won’t have to do anything about it. The exceptions are in cases where a roach keeper wants to maintain a certain female:male ratio, in very small starter colonies, or in cases where the batch of roaches they began with were particularly old. Of course, early death can be a function of stress too, but we’ll assume for the moment that any stress within a colony that could lead to early death would affect both males and females equally.
The reason male die off is usually not a problem in starter colonies is because it only takes about four months for a newborn nymph to mature to adulthood and begin breeding. Taking the very low-end of the longevity range as an example, the life-cycle of an adult male is 12 months. Most of them should survive at least one breeding cycle. Statistically, a random batch of these short-lived males will survive 1.5 breeding cycles, which is plenty of time for them to “replace themselves” through their breeding activities many times over. Of course, this is the worst-case scenario, and males usually live longer than 12 months.
If you notice males living less than 12 months, their shorter lives could be caused by many things. Too much heat, stress, and on and on. The same rules apply for keeping males healthy as stated above for the colony generally: Give them proper conditions including nutrition, keep colony stress low – particularly for the males by reducing their numbers to fit our recommended F:M ratio – and resolve all problems within the colony quickly.
5. Slow colony/nymph growth
One common cause of slow colony “production” is slow nymph growth. In this case, production on the individual roach level may OK, while production at the colony level is not. This situation occurs when nymphs fail to grow or grow slower than normal. New nymphs may appear regularly, but whatever is happening after that may not seem right to the roach keeper. New nymphs keep coming, but for some reason they aren’t growing out.
Nymphs are very sensitive to their environment. They are the first to suffer and die when things go wrong, and as such you can consider them a “leading indicator” of problems. A colony that is doing well by all other measures can suddenly start to lose nymphs, and this indicates a problem. If you’re paying close attention and catch it early, you might be able to prevent a lot of nymph deaths.
If you think this may be happening in your colony, take a look at the common causes of slow nymph growth below.
Dubia roach metabolism slows at low temperatures, which includes room temperature in the average American home. It slows so much that nymph growth stops and the roaches can stay in the same instar (growth phase) for a year or more. This is bad news for breeding, and of course efficiency is out the window.
Nymphs also do poorly in high temperatures. In this case though, instead of living long lives, “doing poorly” means they die. And to top it off, you probably won’t know they’re dying because sick nymphs are small, easy to miss, and they’re probably eaten quickly by larger roaches. You won’t see this happen. You’ll just notice that production seems low, and you probably won’t know why.
Even though these problems become clear earlier in nymphs, the solutions are the same as they are for adult temperature problems. Check the enclosure, make sure to get temperature readings at or near the highs and lows, then adjust as necessary. Then, read through the following causes of slow growth, look into anything you think might need attention, fix any problems you find, then sit back and see what happens.
Low food quantity or quality can affect roach growth, but nutrition issues hit nymphs particularly hard. Not only do they lack the reserves of older roaches, but they tend to fall victim to larger roaches with cannibalistic urges when the colony falls on hard times. Nymphs are an excellent source of nutrition. We know it…and so do other roaches.
The solution again is generally the same as it is for adults that breed slowly. Check their food and provide a balanced diet. There is, however, additional information that you should know about nymphs that will help you solve and even avoid growth problems in the future.
The first thing nymphs do when they’re born is eat their ootheca, or egg sack. Oothecae are very high in protein, so they’re very nutritious. The second thing nymphs eat is frass, or roach feces. Frass is very high in nitrogen, which they convert to protein in a process that in the animal kingdom is unique to roaches. The third thing nymphs do is eat as many high protein foods as they can. The message here is clear: Dubia roach nymphs need a lot of protein.
A caution on protein
However, too much protein (or too much of any nutrient for that matter) is bad for nymphs as it is for all roaches. The same process that allows them to store it can cause harm if they eat too much. It may also lead to some other weird results like malnutrition from overcompensation. We wrote about this in our article titled Dubia Roaches and Dietary Protein. Feel free to use it as a resource if you want to learn more about the topic.
Basically, the takeaway is that Dubia roaches have specific nutritional requirements at each life stage, and it’s very important that their needs are met. Nymphs need high protein for growth. Older nymphs need less. Females crave carbohydrates at certain reproductive stages, and the list goes on…
With a breeding colony that contains roaches of all sexes and ages, it’s impossible to provide one single food that meets all of their needs. The solution is to provide a wide range of foods in whole form. This includes plenty of grains, fresh fruits and vegetables, and whatever other ingredients you want to try. The roaches will eat only what they need. They’re actually very good at doing that. Use this to your advantage.
If your nymphs are growing slow from lack of protein, this will solve it. It may also resolve other nutrition-related issues that you may not know about but that nonetheless affect mating, growth, nymph viability, and more.
Too many males
As mentioned above, males sometimes eat nymphs when competition for females is high. Why this is happens is a matter of speculation, but the answer isn’t nearly as important as recognizing the problem and knowing how to avoid it.
The solution: See above. Get the female to male ratio right, make sure temperature, food, and water are as they should be. If this is causing slow nymph growth, the problem should resolve.
Again, stress affects growth, and a lot of things can cause stress. Check their food, water, temperature, humidity, light/dark cycle, noise and disruption, population density, and housing. Basically everything that has already been mentioned. Clean the enclosure if necessary, stock it with fresh amenities, and avoid chemicals as much as possible.
Dubia roaches need a certain level of care, but part of that care involves letting them be. As a rule, cockroaches are not particularly easy going insects, and Dubia roaches are no exception. In fact, some species will even drop their egg sack when pursued by a predator. While we can speculate about why, this is obviously a stress response. Maybe it works to lighten the load for escape. Or it could be a strategy to cut losses in bad environments so resources can be devoted to surviving and then starting fresh somewhere else. Whatever the case, the bottom line is that healthy Dubia roaches are happy roaches, and happy roaches can reproduce at their full potential when given the right environment.
Summary & conclusion
Breeding Dubia roaches is not without pitfalls, but with a little knowledge and experience, the most common of them can either be avoided or dealt with easily. The trick is to act fast and learn as much as you can. The first place to look when problems occur are related to the colony’s environment. Broadly, that means temperature, food, humidity, and social organization. Once you have those under control, there are some other issues to be aware of that can help you “fine-tune” your colony and increase production.
Of course, if you have any questions after reading this article, or if you think of a topic that should be included but isn’t, please let us know!