Bosc monitors are a great starter Monitor Lizard, if given the regular attention it needs it can become a very tame lizard.
Bosc Monitors are generally a dull greyish colour with lighter oval dotted over their bodies, these can vary between burnt orange and olive green. Their heads are fairly blunt at the snout and wide at the ears. The underside is usually white with greyish dots/lines in an irregular pattern. Its tongue is long and forked at the end, and is pink up until about halfway, then is blue down to the tip. They frequently flick out their tongue when out and about. The size of an adult monitor can vary, the longest being around the 5ft mark, the smallest being around the 2.5-3ft mark, with many falling in between. They are not sexually dimorphic so are difficult to sex as adult.
The Bosc or Savannah Monitor is, as the latter name suggests, a species from central and southern Africa, with range from as far west as Senegal and Gambia, through Mali, Niger and Chad, to as far east as Sudan and Ethiopia. Their natural habitat is usually savannah areas, as well as scrubs, and arid grasslands with hot dry summers and monsoon like winters.
That depends on how much time and attention you give it.
Bosc Monitors are mainly terrestrial, which means that wherever you house them the floor space need to be that of considerable measurements, for and adult the minimum floor space required is something near to 6ft². In saying that though, many of these lizards will climb if they are allowed to do so. Therefore pieces of wood can be added to the enclosure if room permits, just make sure any wood you do get has been thoroughly disinfected before placing into the tank. This can be done by soaking the wood in a bath of boiling water for a few hours, scrubbing with a weak bleach solution, and soaked again. This should be enough to kill any of the bacteria and parasites that may have been on it.
Heating the tank is very important, as these lizards come from a very hot and arid area of Africa. The heating methods are entirely up to you as long as you don't put the animal’s health at risk of burns or overheating. Common methods for heating a large enclosure is by using a ceramic or equivalent heat bulb on a thermostat, with a heat mat covering up to half the length of the tank for a constant background temperature. At night time the light is switched off, or down if on a thermostat, with the heat mat left on 24 hours a day. Temperatures you should aim for should range from 80-85 F at the cool end to 95 F at the hot end. A basking point of up to 110 F is also advisable. These temperatures should be dropped by 10-15 F at night. As with all reptiles, this temperature gradient is essential so that the animal can properly regulate its body temperature (thermo regulate). One point that is worth a mention is that if you are using an incandescent light bulb, it must not be yellow or white as this can disrupt the lizards sleeping, which can lead to stress. A red light bulb is the best option, as this does not seem to keep them awake. Otherwise use a ceramic light bulb, as these stay warmer for a little longer than ordinary bulbs therefore providing a gradual decline in temperature.
With regard to lighting, I let my heat lamps light the cage. I do not have a UV light in his tank in the winter, but I do expose him to natural sunlight when it is a warm day, so he does have regular access to UVB, he also has a 2.0 or 5.0 % UV bulb in the summer. If you wish to include a UV light in your set-up all year round by all means do, as it has not been shown to harm these monitors, as they are diurnal lizards they would have access to a lot of UVB from the sun in the wild.
Substrate again is up to you, but there are a few things that you need to think about:
The feeding of Bosc monitors has been up for debate lately. It basically boils down to whether to feed mainly rodents or insects. My personal opinion is that where they come from they would come across a slightly larger percentage of insects rather than rodents. Therefore I feed mine insects such as crickets, locusts and earthworms, around twice a week, with a mouse about once a week. His diet is supplemented with calcium plus vitamins twice per week. His diet is generally around 60% insects.
Whatever you do decide to feed your monitor, just make sure that it is getting enough exercise as Bosc monitors can get very obese if they eat too much with little exercise. Being obese can seriously shorten this lizard’s life span, which is usually around 12 years, down to anything as low as 5 or 6 years. If your Bosc Monitor does get obese a few laps swimming around the bath every couple of days will do wonders! As well as lessening its food intake obviously!
If you give this lizard the respect and care that it needs and deserves then they can make fantastic pets. Just remember, it didn't ask to have a life in a cage therefore it is your responsibility to give it the best life it can possibly have in captivity.