Problems with Dubia roach breeding colonies are common, but bad outcomes are rarely inevitable. There are usually easy fixes for most common issues at-home breeders face. In fact, there are simple solutions to almost all Dubia roach breeding problems – whether common or not – and the key to raising healthy and productive roaches is almost always a matter of preventing small problems from occurring, identifying and fixing those that do, and acting quickly.
You can skip to troubleshooting by choosing a problem category below. The next few paragraphs are introductory and background.
- 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 most of our knowledge was earned 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. Then we collected, read, and studied all the literature we could find. But reliable information was hard to come by. We spent a lot of time piecing together fragmented data from many sources before we had anything we could use in practice, 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 use as reference. 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 are not the norm in Dubia roach breeding colonies, but small ones are. Lesson #1 is that small problems need to be dealt with as they arise, and it’s not wise to let them fester. Speed is key when it comes to easy fixes and keeping damages to a minimum. And as it follows, procrastination should be avoided. If you do that, the small, common problems will rarely become big ones.
We have 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, and they have very specific requirements that we have to work very hard to meet in North America. And it isn’t always possible to meet them. Food, temperature, light cycles, humidity, air circulation, population – all factors that the roaches largely regulate themselves in the wild. In captivity, however, they rely on us to provide it for them. When things are not to their liking they can neither escape nor complain.
The bottom line is that until you have a good sense of what’s going on it’s wise to act quickly. Don’t put off until tomorrow what can be done today. When you get that good sense of what’s happening inside your colony you’ll probably still not put things off because you’ll know firsthand how dangerous that can be.
If you need reasons why this is the case, consider that it is 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 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 is rarely a problem, a large number all at once can 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.
1. Roaches not breeding
As certain as death and taxes, insects reproduce in the right conditions. That’s not only how they exist, it’s arguably why they exist. They surely wouldn’t exist at all if they failed to breed. If you think your Dubia roaches aren’t breeding, the first (and often only) place to look is their environment.
No breeding at all is cause for immediate concern. If this is the case, something serious is 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 that there may 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 that begin breeding immediately. The time it takes to see babies can be even longer if the females were stressed at any time, so factor that in your thinking. 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 chances it would take this long are slim, but it’s within the realm of possibility. When you end up with babies depends entirely on where you started.
If you can rule out the normal B. dubia 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 that started with optimum breeding and declined from there. 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 and then provide them. The following is a list of the most common reasons 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 will slow. The solution in this case is to lower the temperature. Keep it in the sweet spot as much as you can. If it wanders, find the cause and fix it as soon as possible. A breeding colony can handle some temperature fluctuations, but less and fewer is better.
Where colony temperatures are consistently low, production will also slow. Unlike the production slowdown seen with high temperatures, which is a slowing of colony production, actual individual roach production will slow when temperatures are too low. This means the roaches will reproduce less frequently and give birth to fewer nymphs when they do.
When diagnosing temperature 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 slower 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.
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, be sure 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 seven 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 maximum production.
Reproduction may slow if Dubia roaches don’t have enough food or 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?
- Are you feeding them fruits and vegetables?
- Do they ever run out of food? If so, 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 breed B. dubia successfully 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.
Low humidity can cause a reduction in productivity. Tropical roaches rely on humidity to prevent their egg sacs, or ootheca, from drying out. Dubia roaches are somewhat unique in that they are among the few species that carry their eggs internally, but they still need a constant medium to medium-high humidity to avoid problems.
Buy a hygrometer and maintain colony humidity at 40% or higher. This 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% and boosting with manual misting, an occasional bowl of hot water nearby, or even a humidifier when it drops to 50%. 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, so there is no consequence to overshooting the target. The only thing you need to worry about is the humidity falling too low.
Too many males
Males may have a tendency to eat young nymphs when 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, so males can stress an entire colony with their aggression. Of course, stress can also reduce productivity. Avoid it whenever you can.
The solution is to count the adults and bring the ratio of females to males within range.
So to one degree or another, these are the sources of the majority of Dubia roach breeding problems. When you get food, temperature, humidity, and the social order under control, most problems will clear up or never happen in the first place. Of course, it’s not quite as simple as that, and if you’ve tried everything and nothing is working, or if you want to further reduce problems or the potential for problems going forward, there are some other things to consider.
Strong odors are not a good sign. They indicate mold or some other growth that may cause breeding issues. Dubia roach colonies should not smell bad. If yours does, 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.
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 that is to be expected. In fact, Dubia roaches benefit from frass. It doesn’t smell bad, so frass itself won’t be the cause of mold, and it’s also an inevitable and 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.
We think the way to deal with frass is to clean the colony and remove dead roaches and excess frass, but leave some frass behind. A good target is enough to completely cover the enclosure’s floor but not more than is necessary to do so up to about a quarter inch. More is probably OK, but it’s not necessary, and it could contribute to problems. The deeper the frass the more moisture it will hold, and at some point it will accumulate faster than it evaporates. This is something you should avoid.
Too much light and too much ongoing disturbance can also have negative health effects on your roaches. Shoot for no more than 12 hours of light per day, and keep your roaches away from visual and auditory intrusion as much as you can. Don’t shuffle things around in their bin more than once a day. Less is probably better if you can manage it. The ideal amount would be never, but that isn’t practical, so just keep it to a minimum. Don’t not clean out their food and water bowl out of fear of disturbing them. Use your judgment with the knowledge that less is better.
NOTE: As we’ve 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 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 that don’t have health issues. If you’re unable to find a direct cause, consider doing everything you can to improve the health of your roaches and your colony.
3. High adult mortality
If you notice that your adults seem to be dying at higher rates than before or at rates you think are too high, there are a few things you should 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 separate the remaining adults and nymphs.
- Set up the separated adults and nymphs in new bins with new food, water, and harborage.
- Check the bins at least daily and remove any roaches that die.
- 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 and sudden die-off we later figured out came from a batch of pesticide-laden fruit. That’s when we learned to always wash fruits and vegetables before feeding them to your roaches. A tiny amount of bug spray like Raid Ant and Roach Killer can kill roaches almost on contact even weeks and months later. Pesticides don’t mess around. As they say, they “kill bugs dead”. 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.
What you’re seeing could be caused by something as simple as old age. If you buy a bunch of new adult females as breeders, for example, mate them with a group of males, then remove all the offspring before they mature, in time you’ll end up not just with old females but a group of females that reach old age at the same time. Consider this, if appropriate for your situation, and always let at least some nymphs grow into adults.
Studies suggest the stress of breeding reduces longevity in roaches, but there’s no avoiding that in a breeding colony. You can, however, reduce overall stress by focusing on finding other sources that you can actually control. Overcrowding, too much protein, not enough carbs, too many males, too much light, wrong temperatures, and all the other conditions mentioned throughout this page and our breeding guide can all cause stress, and they can usually all be fixed.
Do a mental inventory and see if you can think of anything that might be causing stress. If there is, fix it and see what happens. You may also consider changing up their diet a bit 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 absolutely relevant to a breeding colony.
4. High adult male mortality
This problem may sound similar to the previous one at first pass, but unless it’s caused by one of the issues listed above, it’s not.
Lifespan difference between sexes
After a while you may notice that the males in your breeding colony begin dying 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 may in fact 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 at least reasonably 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 many times over. Of course, this is the “worst case” scenario, and males usually live longer than 12 months.
5. Slow colony/nymph growth
One of the main causes of slow colony “production” is slow nymph growth. In this case, “production” on the individual level may actually be OK, and production on the colony level is the issue. This problem can occur when nymphs fail to grow or grow slowly. New nymphs may appear with regularity, but what happens after that may not seem right to the roach keeper.
Nymphs are very sensitive to their environment. They are the first to suffer and die when things go wrong, and as such they can be considered a “leading indicator” of problems. A colony that is doing well by all other measures can suddenly start to lose nymphs, and if you’re paying close attention and catch it early, you might be able to prevent a lot of 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 means room temperature in the average American home. It slows so well in fact that nymph growth stops and the roaches can remain 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, rather than living long lives, “doing poorly” means they die. And to top it off, you probably won’t know they’re dying because sick nymphs small, easy to miss, and they’re probably eaten quickly by larger roaches. You won’t see that happen. You’ll just notice that production seems low, and you won’t know why.
Even though problems are evident 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 it hits nymphs particularly hard. Not only do they lack the reserves of older roaches, but they tend to fall victim to larger roaches and their 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. Ootheca are very high in protein. The second thing nymphs do is eat frass, or roach feces. Frass is very high in nitrogen, which they can convert to protein in a process unique in the animal kingdom. The third thing nymphs do is eat as many high protein foods as they can. We think the message is clear: Dubia roach nymphs need high 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!