"monitor" lizard

Cleo's Story

Cleo was a Nile monitor. Most Nile monitors are known for their irrascable dispositions, paranoid outlook on life, high strung nerves, and intractable temperments. Cleo was different. Although not exactly trusting of strangers, she did tolerate being touched and handled in a familiar environment. Her unusual intelligence and quiet presence made her an important part of my household.

Cleo's Beginnings
baby Cleo I aquired Cleo at a repile show in San Francisco in 1994 as a hatchling. At the same time, I purchased a second hatchling Nile monitor which I named Rameses. From the beginning, Cleo was calmer and friendlier than Rameses. She quickly got to the point where she stopped biting and deficating when picked up, and although baby monitors can be expected to be a bit squirmy, Cleo would usually calm down and let herself be handled. She also developed a peculiar habit that lasted throughout her life - she liked to perch on the top of my head. After a few months, Rameses sickened and quickly died, leaving me with only one Nile monitor.
Cleo as a baby. Wasn't she adorable?
(baby photos by Jean Campbell)
baby Cleo

Cleo on a log Cleo at the entrance to her cage

baby Cleo hanging out Cleo was originally housed in a ten gallon aquarium. Monitors, however, grow rapidly, and before long I was forced to move her into new quarters. A 30 gallon aquarium served her needs after I moved to Seattle in the summer of '95, but soon she was relocated to a 60 gallon aquarium, and finally a custom built wood enclosure, 150 cm by 60 cm by 60 cm, with sliding plexiglas doors and screen ventilation on top. This served for about a year. Since monitors are such active animals, they should have plenty of room to roam, and at this time, I felt I had no choice but to let Cleo have the run of the appartment.

Cleo on the Loose
Once let out, Cleo wasted no time in making a big mess. She would climb up the bookshelves, knocking all the books down. She would dig up the potted plants, or just climb on them and break their stems. Nothing was safe, and anything left out soon fell victim to her curiosity. She could get anywhere, even the places that were barricaded off from the ferrets.

At first, I resigned myself to having to pick up the objects that Cleo would occasionally strew about (and dispose of the plants she killed), but before too long, a problem developed. Like most lizards, monitors like to hide in burrows, crevices, and the like. The more inaccessable, the better. This makes them feel secure from big nasty predators, like humans. At first, Cleo chose to hide in the couch. No, not under the couch, in the couch. I feel strongly that I should be able to get to my pets when neccessary, in case a problem arises, for example. Thus, after several days of Cleo hiding in the couch, and not coming out even to be fed, I finally cut the bottom of the couch open to extract her. This ruined the spring supports, so the couch sagged ever after that. Of course, now that her hiding spot was less secure, she had to find some place else. The book case was not that much of a problem, I could just shift the book case. Finally, however, she found the stove.

Cleo and the Stove
Cleo's head poking out of a stove burner By climbing behind the stove, Cleo could get up inside of it. At first, she stayed down by the drawers. By pulling out the drawers, I could get to her. Of course, Cleo didn't like anyone being able to get to her, so she climbed higher. Each time I found a way to get her out, she found a way to make herself even more inaccessable. I tried to keep her out of the stove by sealing off any way for her to get behind it. A stack of books wedged between the stove and the refrigerator were easily climbed. A strip of plywood duct-taped to the entrance fared no better. To seal off the top of the stove, I stuck strips of duct tape between the top of the stove and the refrigerator and the wall. She just went in behind the other side of the refrigerator. I sealed off the entire back of the refrigerator, and she pulled off the narrow grill at the bottom to climb under the refrigerator, and from there to the back of the stove. Finally, my kitchen was a mess of plywood, duct tape and hardware cloth, and still nothing worked. Cleo could get over, around, under, or through and barrier I put up. When I saw her chimney up the narrow crevice between the stove and refrigerator and then dig through the duct tape, I finally gave up. Each time I got her out, though, she went into more inaccessable parts of the stove. Finally, she climbed up into the part on the top-back that has all the dials for setting temperature. This was of solid metal construction, and the only way in required more flexibility that the human arm was capable of. There was no way of extracting her.

She stayed in there for weeks. Sometimes, she would poke her head out one of the burners. One of those times, I was quick enough to run over, reach under the burner, and grab her tail before she could hide away completely. After a prolonged struggle, I was able to drag her, hissing, and scratching, from the stove. After that, I put up a plywood barrier separating the kitchen from the living room (the appartment didn't have doors). Cleo got to stay in the living room. At the time, it seemed a sheer, vertical, one meter high barrier of solid plywood (with a gate thet people could use) was too much for even Cleo to climb. However, I had to clear the area in front of the barrier of all furnature to a distance of one and a half meters, or Cleo could climb up on the furnature and jump up to the top of the barrier. I found out later that Cleo could, in fact, climb the plywood wall, probably by putting her arms and legs on either side of the 2x4 frame that held the gate and pushing inward. This provided enough friction that she could wiggle up, despite the lack of foot or claw holds. My best guess is that she just got tired of the fight, and settled for one of the hide spots I provided her.

Grievous Bodily Harm
Cleo being held Although Cleo was usually fairly calm around people she knew in a familiar setting, she didn't like being restrained when picked up. If you lifted her gently without grabbing, supporting her body in your hands, she would usually just try to calmly walk away. By placing the hand she just walked off of in front of her, you could treadmill her quite effectively, and in so doing so move her to wherever she needed to go. However, when grabbed, or even worse, dragged out from her hiding spot, she would take pains to escape. This involved reaching up with her back feet to get a purchase, usually on your wrists, and then pushing off with those feet to try to run away. Of course, since you had a good grip on her, she wouldn't go anywhere, but her claws sure would! They would be pushed back across your wrists with force, cutting painful and ugly wounds. Fortunately, these lacerations were superficial, but for several days you would have red streaks lacing your wrists, palms, and forearms.

On rare occasions, Cleo was so frightened by being grabbed in such a way that she bit. Nile monitors have very powerful jaws, strong enough to crush clam shells. In addition, the front teeth are quite sharp (the back teeth are blunt, for better crushing). I was lucky in that none of these bites were particularly severe. In one case when she was a sub-adult, she panicked when I was giving her a bath. As she dashed around the bathroom, I grabbed her and she immediatly twisted around and grabbed back, but with her mouth. Since she was not an adult at the time, the bite was not that bad.

Another time, my parents were looking after her when I was ill. When I was mostly recovered, I went over for a visit. Cleo did not seem to like her new home. She was extremely nervous, staying under cover and struggling like crazy when taken out of her enclosure. At first, I thought this was because my parents didn't handle her the entire time she stayed with them. After telling them they should take her out more to get her used to humans, I took my mom to show her how it was done. Of course, Cleo chose that time to bite. It was not a very good bite, she only barely got a hold of some skin on the back of my left ring finger with the side of her mouth, but she held on like a bulldog with crushing strength. After putting dijon mustard in her mouth and prying at her jaws with a butter knife, we were able to release her grip. The wound bled freely, but after being disinfected with peroxide and wrapped up, it healed without incident. I still have a scar. I fear the bite could have been much worse if she had gotten a more solid grip, possibly ending with a broken finger bone.

Cleo doesn't want to pose for the camera Perhaps the most curious of the bites I recieved from Cleo came not because she was nervous, but because she was hungry. As mentined earlier, Cleo liked to climb on my head. When she was small, she would hide among my hair. As she grew, she could no longer do this, but she still liked the high, warm vantage point. I did discover a potential problem, though. It seems that the shaving cream I used that day smelled irresistably tasty. Now monitors have an incredible sense of smell, and even the remotest residue to a substance can be picked up. I'm guessing that she smelled the chemical trace of the shaving cream I had used earlier that morning, because as she was climbing up toward my head, she bit my chin. Fortunately, she quickly realized her mistake and let go. The bite was not very bad.

Cleo undoubtedly bit me several times when she was just a hatchling and still getting used to me, but the bites of a hatchling monitor are comical rather than dangerous.

In addition to biting and clawing, monitor lizards can use their tail as a sort of a combination between a whip and a club. Only once did I sustain any noticable injury from her tail, when I was trying to put her away when she was being obstreperous. In her lashing about as I held her, her tail whacked my arm and left a welt. She would commonly employ her tail against the other animals in my house, however. Monitors use their tail as their first line of defense when approached to closely. Blows from the tail keep threatening animals far enough away to avoid close physical combat. Cleo would bludgeon and lash the savanna monitors, the ferrets, and even some cats I was looking after for a while. They all learned that Cleo wasn't very fun to play with (although the cats seemed to find Cleo's long tail irresistable).


Cleo spent much of her time basking. She had a number of basking spots to choose from, scattered about the living room. It was not uncommon to see her stretched out under the "light table," or shacked up with the savanna monitors under the contraption I nailed together to hold their basking lamps. When she got good and warm, she would explore a bit, or go crawl into her hiding place for a nap. She also liked to rest on top of the highest cages, well above the level of my head. Perhaps it was because warm air rises, but maybe she just liked the view.


As my pet, I tried to feed Cleo a varied diet. I'd often hard-boil an egg for her, and she would have fun crushing it, pulling it apart, eating all the bits, and then spend hours sniffing the shells. I could give her a handful of beetle larvae I got from the pet store, and she would dig around for them and eat them, one by one. Goldfish by the dozens could be dumped into her water dish for her enjoyment. Crayfish were collected from nearby rivers, and she would crunch them up, while making a mess of their guts. On rainy days, I would collect earthworms and snails off the sidewalk. Snails would be crushed with enthusiasm, earthworms slurped down like animated spagetti. Sometimes, she got the kind of cat food with sliced chunks of meat, so she could easily pick them out without making too much of a mess (cat food is high in fat, though, and should probably only be fed sparingly to adult monitors). When I was eating meat for dinner, Cleo would often get a few pieces.

What Cleo ate most, though was mice. This was largely a matter of convenience, since mice could be bought in large numbers fairly economically. At first, I gave her live mice. After a while, I stopped this practice, for two reasons. One is that an adult mouse is equipped with chissel-like incisors that can make a narrow but deep wound. Such a wound can be easily infected and become fairly serious. A monitor is more than a match for any mouse, but sometimes, the mouse gets lucky. The other reason was convenience. Frozen mice are cheaper, stink less, are easier to catch, don't bite, and don't have to be cleaned, watered, and fed. They can be bought in bulk and stored in the freezer until they are needed. A weeks worth can be thawed at a time and stored in the refrigerator, then fed at the rate of one per day.

She also got a lot of a mixture of ground turkey, ground calcium supplement, and mutivitamins. I'll usually scoop out spoonfuls and either freeze or refrigerate them, depending on how long I have to store them. A standard spoon scoop provides a bite size chunk and one day's meal.

The End
Late in 1998, Cleo died from an infection of the heart valve. She was four years old. I found her in the morning when I was going round to feed the all monitors, lying cold and unresponsive, curled up in a corner near a heat lamp. She showed no earlier signs of illness. I took her remains to the vet for an autopsy, and there said my final goodbyes to this wonderful lizard.

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