Water Monitors- for Reptiles Magazine by Robyn Markland/Pro Exotics March 2003
I love talking about monitors! We are in a very exciting time for understanding monitor lizards, the hobby as a whole is really making some great advances in monitor husbandry, captive breeding, and overall monitor theory.
Just ten or fifteen years ago, most keepers kept monitors the way they kept their snakes, matching general temperatures, cage setups, and even diets. As we learn more about the lizards and their basic needs, we are able to make strides not just in captive husbandry, but in breeding as well.
These advances in husbandry, the breakdown of the basic requirements and strategies to keep monitor lizards alive and healthy over the long term, have opened up the hobby to an entire new generation of keepers. Monitors are absolutely booming in popularity!
One of the most popular pet monitors available today is the Water Monitor (Varanus salvator).
The Water Monitor is the largest lizard that you can possibly own, dwarfed only by the mighty Komodo Dragon. An average adult Water will reach at least 6 feet from tip to tail, and can easily weigh 60-70 pounds. That is a lot of lizard!
Waters can be a fine choice for a monitor if a keeper is well prepared, but there are definitely pros and cons to be weighed before making this potentially giant acquisition.
Simply because of their sheer size, Water Monitors cannot be considered a beginner reptile. Babies may be fairly inexpensive to purchase, and 12 inches of baby madness may not seem like a big deal, but for this type of decision, you have to look 1, 2, 5, even 10 years down the line, and consider the awesome future of the this reptile, and what responsible ownership really means.
A six foot eating machine is an expensive reptile. The reasonable initial investment will quickly fade when you are faced with building a 12 or 15 foot cage for your giant monitor. That time will come much sooner than you may think.
No pet store sells a monitor cage ready for a 6 foot Water monitor. As you will learn, snake cages are NOT reasonable environments for monitor lizards, they simply do not allow for the temperature gradients, the substrate requirements, and they certainly don’t have the square footage necessary for such an active animal. You are most likely looking at a custom cage, or perhaps a remodeled room, to accommodate this type of reptile. These custom environments can run from $500 to $2000 or more, and that investment will come due not in 5 years, but more likely just one or two (what what WHAT?!?).
And where does a 15 foot cage go? Probably not in the living room. Many keepers end up putting large monitor cages in the garage (there goes the car) or in a basement, and now you have just doubled your heating bill, because those rooms are often COLD, and will have to be specially heated to meet the needs of your new housemate.
Don’t forget that big monitors have a BIG appetite, and they can put away a lot of food. Before you make your final decision, don’t forget to factor in your monthly, and yearly, food bill. Monitors don’t eat table scraps, they eat a balanced, nutritious, healthy diet, and you may very well need clearance from the head of the household to keep 50 pounds of frozen rodents in the family freezer!
After that food goes in, it comes right back out. Monitors have a quick metabolism compared to snakes, they make efficient use of their food, and return the extras right back to you. If you stay on top of your cage cleaning, the smell is no worse than your favorite ball python, but let a 50 pound monitor go for a week without cleaning, and your neighbor may well call the National Guard.
Monitors are a lot of fun to keep, and I absolutely recommend them, but if you are not yet prepared to make the time, space, and financial commitment required for a Water monitor, there certainly are other choices. Small 2 foot monitors like the Acanthurus (Ackies) don’t require nearly the caging and feeding needs of a large Water. That would be a much better choice for a beginner keeper, start with a scooter before you try and drive the tank.
It is all about responsible ownership. Huge lizards are incredible visual animals, I certainly love going to the zoo to see the Komodos, but the novelty of size wears really fast. When you choose a new reptile, choose wisely, and make sure that you can fulfill the lifelong needs of that reptile. There should be no disposable animals.
For the keeper truly capable of caring for a giant monitor like the Salvator, you are in for a special treat! Waters have great personality, and like most monitors, are inquisitive, interactive, and reward keepers in ways that snakes simply cannot!
So where to start? Start with a baby! Why? Why not jump a year ahead of schedule and find a juvie or adult animal for sale? Because you will have the best chance of success with a baby. You are in it to win it, and you want the strongest, prettiest, healthiest adult Water possible. You will greatly increase the odds of that success by doing the work yourself. Raising a baby yourself allows you to completely control the variables, both good and bad. You can ensure proper husbandry and a great diet, and in a very short time (it goes by quickly) you will have that polished, beautiful, full sized adult Water you have been dreaming of.
Aside from that, you can’t expect someone else to do all the hard work, all the blood, sweat, tears (and rodents) and NOT expect them to ask primo dinero for a gorgeous adult Water. The blood, sweat and tears are the investment, put in that work yourself, and reap the rewards.
You can purchase baby Water monitors from a number of sources. Pet stores sell them, reptile shows sell them, if you are lucky you can catch one of the few U.S. captive bred babies available each year, and you can find them on any one of 3001 internet sale sites.
Always demand the best when choosing a new reptile (monitor or otherwise). Don’t start with a pity case or “pet store rescue”. No matter what the “savings”, don’t pick a half dead bag of bones out of an unheated 20 gallon aquarium filled with 2 dozen limp babies sitting in an inch of stale water (“Dude, it says they’re WATER monitors!”- does that spark any old reptile show nightmares for you?). Why folks dream of that fabulous new reptile addition and then start themselves six feet in the hole absolutely mystifies me.
Choose a healthy, vibrant, alert, solid animal! A healthy Water monitor baby should feel strong in the hand, and while it may become your tamest lizard ever, for that first contact, it should be defensive, fairly scared, and awfully skittish. As far as that baby knows, you have just chosen your next lunch!
Make sure the eyes are clear, and there is no mucus or excess saliva in the mouth. Make sure there is a full compliment of toes and nails, and check to see that the tail is complete and in good condition. There should be no stuck sheds, and if the animal is currently in shed, the shedding skin should come off fairly easily, although keep in mind that monitors shed in pieces, and over a few days, not in one long piece like the more familiar snake.
Monitors store fat in their tails, and the hips are a good indicator of an animal’s general condition. The hip bones should NOT be visible, the tail should be full, thick, and round at the base. The legs and belly should also have good tone, and while they should not look stuffed like a sausage casing, the should have good muscle quality and a strong, full appearance.
Once you have made your selection, you need to maintain that great bill of health, and in order to do that, you need a great setup.
At Pro Exotics, we always suggest new customers start with a smaller cage for babies. Smaller cages are easier to control temperature wise. It is easier to monitor food intake and observe and react to your new animal’s progress. We like to start our baby Waters in a 10 or 20 gallon long glass tank.
Water monitors do not need a large pool of water to swim in, so that does not need to dominate your cage space. What you do need is a good moist substrate, some good hiding spots, a water bowl, and an appropriate temperature gradient that covers both ambient and basking temperatures.
Temperatures are one of the aspects of monitor husbandry that have changed radically over the past 15 years. I remember in the early 1990’s keeping monitor babies (not very successfully) with basking spots of 90-95° F. That is hardly even warm. But that is what all the literature said (and much of it still does). If you are new to the vanguard of monitor husbandry, you might want to sit down before you try and understand our current accepted minimums for basking temperatures. Here we go…
120-130 degrees. Fahrenheit. Absolutely.
Now before you split your britches, understand a couple of things. Number one, we are talking about BASKING TEMPERATURES. At their hottest point. Ambient (general) cage temperatures should be in the low to mid 80’s. But basking temps do indeed run into these ranges.
We are also talking about SURFACE TEMPERATURES. Not air temperatures, and certainly not body tissue temperatures. We are talking about basking temperatures that allow the lizard to fully metabolize and function as a cold blooded, highly active reptile.
With temperatures being such an important part of successful monitor husbandry, you are going to need tools to measure those temperatures accurately and effectively. Before you make your monitor purchase, get yourself an infrared Temp Gun, and some Minimum/Maximum Digital Thermometers with probes. These tools will become your best friends.
You can either trust me on this temperature thing, or test it for yourself. Take your temp gun out on a hot summer day, let’s say a moderately warm day of 90° F, the kind of day you might have in Indonesia , the home range of the Water monitor, and find a nice absorbing surface in the direct sun. The kind of surface you would find a monitor basking on. A rock, or for simplicities sake, the asphalt in the street.
Now even though the air temps hover in the warm but tolerable range of 80-90° F, you will find these heat thirsty “basking” spots run well over 110° F.
Monitor breeders trekking in Indo and Australia have directly temped out animals basking on surfaces surging past 160° F! It gets way extreme, and when you first try to wrap your mind around a temperature like that, it can indeed be very difficult.
But for a monitor, it is the difference between barely hanging on at 95° F, or growing, thriving, and even breeding at 130° F or more. We regularly use basking temps of 160° F for adult breeder monitors, and they make regular use of it, but with babies, we run the lower basking temps of 120-130, as they are not into egg production or breeding cycling.
I really can’t stress enough how important temps are to your monitor. They are the single biggest factor, and most commonly overlooked, to having success with monitor lizards. Don’t sell yourself or your animal short by relying on the cheapest dial or color changing “thermometer” you can find, and for goodness sakes don’t pull the old “lick your finger and put it under the light” technique, after which you invariably say “Seems hot enough to me!” Because it isn’t. Get a high quality thermometer, get a temp gun, and learn to use them. They will become your most valuable tools for your entire collection, not just your monitors.
Achieving these temperature gradients in a cage is not that difficult. It doesn’t require a 250 watt “Super Bulb” to get your basking temp just right. You just gotta know the tricks!
The simplest trick is using an elevated basking spot. If you set up your cage so the basking spot is elevated to within just a few inches of your light (remember that we are talking about a cage setup for a baby), you will indeed be rocking those ideal temps. In a 20 gallon setup, we can easily achieve a temperature gradient of 84-125° F by setting up a 45-65 watt bulb reflector lamp on one end, and creating a basking spot that very nearly reaches the top of the cage.
You can use cork bark flats and tubes to get up there, or you can use stone, perhaps sandstone or slate. Be careful when choosing your basking material though, don’t use cardboard or paper, and if you use rock, consider very carefully the possibility of the elevated spot toppling and crushing your precious new baby.
At PE we use a stack of wood panels that have been adapted and modified from an idea first popularized by monitor breeding guru Frank Retes from the Goanna Ranch.
The wood stacks are made from 1/8 inch wood paneling and 2x2’s, and they can be stacked just about as high as necessary to achieve the proper temperature gradient. We use stacks of 4 or 5 in our baby Water setups, and what you achieve with their use is quite amazing. Pull your temp gun out again…
On the top of the stack, right under the basking light, you will find those top temps of 120-130° F. As you go down through the stacks, level by level, you will find the temperature steadily dropping 5-10 degrees. At the bottom of the stack, you will find temps that just about match your ambient cage settings of 84° F or so. We cut a center access hole in our stacks, to allow for easier animal movement, and for a better temperature gradient as well.
The monitors absolutely love their wood basking stacks. Depending on their current temperature needs, they make use of every level. When you extrapolate it out, for a 20 gallon cage, you have effectively more than doubled your usable floor space.
The narrow spacing between the stacks makes for a fine hiding spot, and for home use, I would even considering adding cloth or denim sheets to the sides of the stacks to provide an even darker and more secure hiding area for these initially shy reptiles.
You are shooting for that overall daytime temperature gradient of 84-125° F. At night, you can turn off your basking spot, but you still want to have some ambient heating, whether it be room heat (for those that have a dedicated reptile room), a night bulb, or a ceramic bulb. Your nighttime target temperature is going to be 80° F, or at the very least, the very high 70’s. Baby Water monitors are not “more prone” to respiratory illness than other monitors, but they will react quickly if you are not on top of your temperature game. Unknown nighttime temperature drops are where most new keepers make initial mistakes. Of course, with that new Min/Max digital thermometer ($20 or less through a dozen different sources), you will know exactly what you have happening in the cool of the night, and you will be able to react and adjust accordingly.
The substrate that you choose for your Water monitor baby is another important factor in your potential success.
While “Waters” do not live primarily in the water, they do need a moist substrate in order to thrive. Aspen bedding, newspaper, sand, or other dry substrates are inappropriate and will literally suck the life out of your animal.
We have used cypress mulch for many years with our baby monitors, and I have always liked it for that application. It holds moisture and cage humidity well, is easy to spot clean, and keeps Water monitor skin in good condition. Cypress is widely available in the southeast portion of the country, but becomes harder and harder to find the further west you head. Check with your local gardening or landscape center for availability. Zoo Med also makes a cypress mulch product, it comes in small bags under the name Forest Floor, and is available through many pet stores. Wood mulches are not all interchangeable, cypress works, most others don’t, and keep in mind that cedar can be toxic to reptiles.
For a baby Water setup, you want to offer at least a couple inches of the mulch. You will want to keep it damp, but not wet, and we typically add water to it every couple of days to stay in balance. Add enough water to achieve a good rich color in the mulch, but not so much that there is any standing water. Watch the cage for evaporation rates (you may want to cover a portion of the cage lid to prevent rapid loss of water content) and add water accordingly. It only takes a couple of weeks to develop a feel for how much water to add at a time to achieve your balance.
While the mulch has worked well for us in the past, we are always looking for ways to improve our monitor husbandry, and sometimes changes can smack you straight in the forehead with their simplicity and effectiveness.
The most significant change we have made in the last 5 years of keeping monitors is in our substrate. We have changed most monitors over to a diggable, burrowable soil substrate. Soil is easily the best substrate for a monitor, it is very natural, and if you could grade soil as 100% effective and appropriate for monitor use, cypress mulch would barely crack into the 70th percentile. There is that much of a difference.
I think that for practical use, keeping monitor babies on cypress for the first few months is fine. It can be very awkward and dangerous weighing down a 10 gallon glass tank with 30 pounds of dirt, cypress will serve the purpose well and you will move past that initial stage soon enough. Once you move on to an intermediate sized cage, or your final adult Water cage, I think a good soil is easily the best choice, and I would bet that once you try a good soil, see your animal burrow, explore, and generally thrive in a good soil, you will never turn back.
Of course, describing a good soil is not as easy as it sounds. I can tell you what it is not. It is not sand. It is not potting soil. It is not straight topsoil. And no, it is not a 50/50 mix of cypress and topsoil. It takes a lot of trial and error to find a good soil, you literally have to get your hands dirty, try different dirts, and see what works.
A good soil holds moisture well, digs well, holds a burrow well, and serves the animals well. You can check out some of the soil information at proexotics.com, and I am even willing to offer a phone consultation on “good soil” to anyone who needs. All 55,000 readers of the magazine if necessary. I just can’t capture the difficult and subtle topic of soil in this article. Start with cypress mulch for your baby monitor, and take it from there, you will be fine.
Once you have your setup ready, hidespots, water bowl, moist substrates, and ideal temps, your cage should be ready for the actual animal. Balancing those temps and moisture levels is not the easiest task, so have that cage running for a few days before the arrival of your new Water monitor baby.
Water monitor babies are not the most confident lizards available, in fact, they are pretty shy and defensive. They are well known for taming down quickly, and making for predictable and tractable adults (there are always exceptions), but for the first few months, they may act defensively, they may bite, and you may not see them out and about as much as you would like. During the initial acclimation period, limit interaction and personal time as much as possible. Your priority is to let the new baby settle in, explore its new surroundings, find some good hidespots, good temps, and then settle in to a good eating pattern. Chasing the animal around the cage with your gargantuan predatory paw three times a day DOES NOT speed the acclimation process along, nor does it speed up “taming”. Your personal interaction time will come later, once the animal has settled in and you have gained its confidence, primarily through food.
Start offering food to your new Water the day after arrival. Keep in mind the monitor will feel very exposed and vulnerable while feeding, so it may be very reluctant to feed in front of you. A baby Blackthroat monitor may tear through 2 dozen crickets 6 minutes after arriving, a baby Water monitor will not. For the best response, offer your prey items at night, so the animal can feed in the still of night, in peace and quiet. Count your prey items, so you can calculate your baby Water’s daily intake. Feeding in controlled portions lets you easily monitor feeding response and appetite.
Baby Water monitors are not meat grinders. They are small lizards, with small digestive systems, and need a good amount of roughage to keep things flowing smoothly. Baby monitors are built to eat bugs, lots and lots of bugs. At Pro Exotics we feed our baby Waters a diet of crickets, superworms, roaches, rodents, and raw ground turkey.
The insects are the base of the diet, and are offered 4 days a week. Rodents are offered one day, and the raw ground turkey (mixed with crushed vitamins and calcium) is also offered on a single day (both meats are offered in controlled portions). That adds up to 6 days a week. I would say 5 days is the absolute minimum I would consider a healthy feeding schedule for a rapidly growing baby monitor.
With the right basking temps to allow for metabolism, it is pretty tough to overfeed a growing monitor. We offer as many insect feeders as the babies will eat (have you ever tried feeder roaches? Monitors LOVE them!). There is always a supply of insects available to the monitors.
We approach the meats in the diet differently. Once again, with proper temperatures, your monitor will have little trouble digesting just about any food item in moderation. But while many new keepers love the action involved in feeding their monitors rodents, that doesn’t always make it a great idea.
With those little tiny digestive systems, that meat intake can get awfully heavy. It would be like you eating a 9 pound pot roast every day for 3 months straight, you can’t tell me that you wouldn’t feel a bit sluggish, cramped and a bit unhealthy after that constant load of meat. Certainly as the monitor grows, the diet becomes primarily meat based (after the first year or so), but for your new baby, try to stay focused on insects, at that size, that is what they are built for.
The rodents we use for monitor feeding vary with the size of the animal, but another significant change we have made over the years is the move away from pinkie (newborn) mice altogether. We feed our monitors primarily thawed rodents, and for babies or smaller species like Ackies, we feed mice (adult Waters and Ionides eat a lot of rats). We use crawlers and hoppers quite a bit for baby feeding, including the Waters.
Mice that have moved past the “pinkie” stage, once they have started adding weight and fur, are going to be much more nutritious for your animals. Pinkie mice are kind of like miniature sticks of butter. Lots of fat, little in the way of nutrients. Older mice have started adding bone structure (calcium) and have a nutritious gut load that consists of more than just milk. Crawlers and hoppers are a better choice for your animals, and the health of your monitor over the long term will be better off by making this menu decision.
On a well balanced, nutritious diet, and with proper husbandry and care, you can expect your 10-inch hatchling Water monitor to be a bit better than 4 foot long at the end of the first year. You read that right, and 4 feet is a lot of lizard (remember all that custom caging talk?). This is a tip to tail measurement, and while the animal will not have added the true mature bulk at the yearling size, you can be assured that more growth is soon to come. By the second year, you will have that full sized, giant monitor that was the goal from day one.
Monitors are time consuming animals. Any animal that eats this much, grows this fast, and needs this much attention to caging and care is going to be a handful. Monitor lizards are a lot more work than boids. There is more feeding, they have a faster metabolism, and your monitors can go downhill a lot faster than your snakes.
For new monitor keepers, stay on the proven path as much as possible. After you have kept monitors successfully for a few years, you can start trying different ideas and theories, but when you are just beginning your monitor adventure, stick with a proven, healthy plan, otherwise it will be your monitor paying the price for any mistakes.
If you insist on trying your own recipe, ballparking your temps, using the most “convenient” substrate, or creating your own dietary plan, you will NOT get the same results. We use our method because it works, it has been proven over the long term by many experienced keepers, and we have already paid the steep price of mistakes. The details of our husbandry are not interchangeable. If proper temperatures are not “achievable” for you, or if you simply cannot resist the temptation to feed your monitor bacon, catfood, and BBQ chicken wings, then monitors are not for you. They are not toys or playthings, and they are not disposable animals.
One of the greatest things about monitors is the application of knowledge. Captive monitor care is amazingly consistent across the board. There are subtle variations for humidity, size, diet and such, but the basic setup remains the basic setup! That is to say ANY GOOD MONITOR INFORMATION is GOOD MONITOR INFORMATION FOR YOU! You can apply the strategies and theories in this article to any of your monitor species. Any good monitor literature will have gems of information and insight that you can apply directly to the species you work with. That is one of the “secret” keys that make monitor husbandry and breeding so much fun. We are constantly learning, reading, and discussing monitors as a community, and we are constantly fine tuning and improving our own monitor abilities. I have worked with many reptile species over the years, monitor lizards stand out as one of the most fascinating, and fun, reptiles for captive care and adventure.
For more information on monitors, soils, nutrition and husbandry, check out the caresheets and FAQ’s at proexotics.com
Thanks to Chad Brown for unwavering reptile dedication and thanks to Nicci, she’s a great wife.
© 2002-2003 Pro Exotics Inc.