There is a great debate that has been raging for decades in reptile-keeping circles, do we need to mimic the wild environment of our animals, and I’m including isopods in that statement. The other side to that debate is that animals are variable, and other than some unusual species most will thrive in a healthy middle ground. Some isopods are considered ideal species for beginners due to their resilience and ease of care.
You are hopefully looking to buy isopods that are captive-bred and sold from here in the UK. It’s no use finding isopods for sale, doing your research on the correct species, and not seeing that pay off in terms of a thriving colony. Isopods make great pets for those interested in low-maintenance, fascinating creatures. So what is humility and why is it important? Remember, proper care is essential for a thriving colony.
What is humidity?
Humidity is the amount of water vapour in the air. The hotter the air the more water vapour it can hold. So if you have an enclosure at 20ºC, that can hold twice as much water vapour as the same enclosure at 10ºC if everything else remains the same.
Maintaining the correct temperature range is crucial for isopod health and activity.
Since temperature affects how much water vapour the air can hold, it also impacts humidity levels in the enclosure. Different isopod species prefer temperatures within specific temperature levels, so it is important to monitor and adjust both temperature and humidity to suit their needs.
To maintain stable humidity and temperature conditions, avoid extreme temperature fluctuations. Sudden changes in temperature can negatively impact isopod health, so always aim to avoid extreme temperature fluctuations in the enclosure.
Measuring humidity levels
Reptile and other exotic keepers tend to use relative humidity. That is the percentage of water vapour in the air for that temperature. Compared to how much that is theoretically possible. Measuring humidity is a lot more difficult than the cheap humidity gauges would have you believe.
To maintain humidity within the optimal range for isopods, it is important to use reliable tools such as hygrometers and regularly monitor the enclosure.
You can have 100% humidity in a vivarium that is cold, but that isn’t as much water vapour as a warmer vivarium at say 60% humidity. The two numbers are linked, and we have to ensure that both are dealt with. A moist environment is necessary for isopod health and natural behavior, so keeping the humidity consistent is essential.
Controlling humidity in a vivarium or terrarium
The first step is to find and establish the correct temperature for the species you are keeping. Cubaris sp. such as Panda Kings or Rubber Duckys generally come from warm tropical regions, whereas Moo Cow Isopods thrives in slightly cooler conditions. As the temperatures lower the amount of water vapour in the air will naturally drop. This is the reason you might see condensation on the glass or sides of your enclosure in the morning after a slightly cooler night. The cooler air holds less energy, and the water vapour condenses on the colder surfaces. Proper ventilation is important to prevent mold growth and maintain healthy humidity levels in the enclosure.
There is nothing wrong with a cooler nighttime period. Even in the tropics, the air temperature will drop overnight. That wonderful time when the mugginess of the day gives way to the refreshing evening air. Just make sure that you don’t let it fall outside of the safe range for your isopods.
To help keep the humidity levels in the correct range you want a substrate that will retain moisture, and release it as the air loses water vapour and dries out. Using moisture retaining materials such as sphagnum moss and bark helps maintain the necessary humidity. For isopod keepers, the good news is that leaf litter holds humidity well, but there are a whole host of other substrates to consider, from mosses to coconut husks, cork bark as a substrate enhancer and source of hiding spots, and other natural moisture-retaining substrates. Adding leaf litter to the substrate helps retain moisture and create microclimates. Be careful that they haven’t been treated in any way as some plant products have to be treated for pests before being imported. The substrate should be kept moist but not waterlogged. Incorporating organic materials like leaf litter and coconut fiber mimics natural habitats and supports isopod health.
A plastic container is a great choice for an enclosure, as it helps maintain humidity and provides a secure environment for your isopods. Be sure to provide hiding spots such as cork bark and leaf litter to support natural behaviors. Ample hiding spots reduce stress and promote breeding success.
Why is humidity important for isopods?
Isopods moved out of the ocean in evolutionary terms without lungs in the way we think of them. Ours are internal, giving our body a chance to regulate things, such as the humidity of the air before it hits our lung sacs. Isopods have pleopodal lungs, these are external for most species of isopods, meaning that their lungs are exposed to the outside air with no chance for the body to add humidity before it comes into contact with the features designed to get oxygen into the body. Because of this, isopods have specific moisture needs, and their respiratory system requires a consistently humid environment to function properly.
For all animals, the humidity can influence body temperature, how wet or dry their skin is, how their eyes function, and so much more. Isopods are no different. Their hard exoskeleton provides protection, especially when they curl up to defend themselves from predators. Proper exoskeleton development is essential, and providing adequate calcium sources, such as cuttlebone or crushed eggshells, supports healthy growth and strength of the exoskeleton. When it comes to reproduction, female isopods use a specialized brood pouch to carry their eggs, offering a protected environment for developing embryos. To support growth, reproductive health, and overall wellbeing, it is important to provide all necessary nutrients, including protein sources, as part of a balanced and nutrient-rich diet.
Species-Specific Humidity Requirements
When it comes to isopod care, understanding the unique humidity requirements of different isopod species is an essential part of creating a suitable habitat. Not all isopods thrive under the same conditions—some species need a consistently humid environment, while others are more tolerant of moderate moisture levels. Researching the specific needs of your chosen isopod species is the first step toward ensuring their overall well-being and happiness.
For example, species like Cubaris murina prefer a humid environment with humidity levels ranging from 70-85%, while Porcellio laevis can do well in slightly drier conditions, with a humidity level of 60-75%. These differences mean that the ideal conditions for one species may not be suitable for another, so it’s important to tailor your enclosure setup accordingly.
To maintain the proper humidity level, start with a suitable substrate that retains moisture without becoming waterlogged. Materials such as coconut fiber, sphagnum moss, and leaf litter are excellent choices, as they help maintain moisture levels and mimic the natural environment of many isopod species. Adding decaying organic matter, like rotting wood and leaf litter, not only supports humidity but also provides a food source and encourages natural behaviors.
Regular misting of the enclosure is necessary to keep the humidity within the desired range, but be careful to avoid excessive moisture, which can lead to mold growth and the proliferation of harmful bacteria. Adequate ventilation is equally important—proper airflow helps prevent stagnant air and keeps the environment clean and healthy. Make sure to remove uneaten food and waste frequently to prevent mold and maintain a clean environment.
A shallow water dish can be included to help regulate moisture levels and provide a source of clean water, but it’s crucial to avoid stagnant water, as this can quickly become a breeding ground for harmful bacteria. Always use a shallow dish and change the water regularly to support your isopods’ well-being.
In bioactive enclosures, isopods play a vital role in breaking down decaying organic matter and maintaining a balanced ecosystem. By providing the right humidity levels and a suitable substrate, you help your isopods thrive and contribute to the overall health of the enclosure.
Creating a slice of nature
Looking just at humidity, how would we a keeper, many thousands of miles away from the natural habitat for our animals, know what the correct humidity is? Especially given we know so little about many of the species arriving into the hobby? It is important to note that different species of isopods may have unique humidity and temperature requirements, so researching the needs of your specific species is essential.
To ensure optimal living conditions, it is crucial to check and maintain the enclosure regularly by misting, cleaning, and monitoring humidity and temperature levels. This helps create a stable environment that mimics their natural habitat.
For a thriving colony, isopods should be fed a varied diet and provided with regular feedings. Proper feeding practices include offering foods such as leaf litter, fruits, vegetables, and protein sources like shrimp pellets, while removing uneaten food to prevent mold. Supplementing their diet with crushed eggshells as a calcium source supports exoskeleton development and overall health.
Climate vs. Microclimate
Climate is the average weather conditions for a particular area over a long period of time. A microclimate is a small area that has different conditions from the surrounding area.
An important aspect of successful isopod care is considering both the overall climate and the specific microclimate where the isopods live.
We need to consider both of these, the climate in Thailand is hot and humid, but is that going to be the same in a large cave, or a small cave? The weather in the UK tends towards cold and wet with moderate humidity, but again is that true in a cave deep underground? In fact, the two caves may share more similarities than we might think. In the leaf litter on the forest floor, there is yet a different set of conditions. It is in these microclimates that we find our isopods.
Hallaniyat Island ‘Oman’ Isopods are a great example, their habitat is famed for being dry and barren, but even the driest deserts have climate shifts and microclimates. These isopods are generally nocturnal, coming out in the less-drying nighttime air. Spending the day in the crags and rocky piles that dot the landscape. Just like a plant pot on your back patio will harbour a damp area even in the height of summer, there will be pockets of higher humidity. But beyond that the annual monsoon season means that 6 months of the year fog rolls in off the ocean, increasing the humidity for at least parts of the day.
Many of the desert-dwelling isopods take things a set further, digging burrows to hide in during the heat of the day. Once night falls the air cools and falls, the water vapour condenses out in the depths of the cooler burrow, giving them moisture for hours and even days to come.
A healthy medium with decaying organic matter
Many species can survive and thrive in some sort of healthy medium, but it’s well worth creating an environment to allow them to thrive. Let’s be honest you’re spending time and money on buying and keeping isopods, and all the other inhabitants of your vivariums or terrariums. Spend the time to get things right before you add any inhabitants, that way it will be a lot less stressful in the future.
To maintain a healthy environment and prevent mold growth, regularly clean the enclosure and remove any uneaten food.
We don’t tend to worry about the nitty-gritty of isopod care when we buy them. But consider how much money you can save in the long term by breeding your own isopods from foundation stock. Get the care right and have a look at some of the rarer isopods we stock. A small group can grow into a large colony soon enough.
Gradients
There is another option, that I think more keepers need to consider. Gradients. That can be along the length of an enclosure, or as you go down through the top levels of the substrate. Plants will allow some areas to be more humid than others.
Let's look at a reptile vivarium, good practice now for a lot of species is to have a temperature gradient, with a warm and a cool end. That means that the air at one end is being warmed more than the other, meaning that the humidity in real terms is higher at one end than the other. Isopods can therefore choose where they want to be in terms of temperature and humidity. Now let's not put a species that likes drier conditions in a vivarium that ranges from 70-95% relative humidity. But creating a gradient gives you the peace of mind to know there are safety margins in all directions.
Overall
Do your research so you know the correct humidity range for the species you are keeping, ensure you have a good quality substrate that mimics their natural environment, if suitable have a drainage layer, and mist your enclosures at regular intervals. Use a good quality humidity meter to measure the levels, and you'll be on your way to happy and healthy isopods, that will breed regularly.
