Throughout sub-Saharan, eastern and northern Africa.
The adult Nile monitor has a reputation for being aggressive and ill-tempered. Captive Nile monitors need large, spacious cages with water containers large enough to allow swimming and soaking. Because Nile monitors are also arboreal, their cages should be furnished with branches or elevated shelves for basking.
In captivity, young Nile monitors will thrive on various insects, small fish and newborn rodents, while adults will live on shellfish, mollusks, fish, chicks and mice (heavily furred mammals should be avoided).
Nile monitors require temperatures ranging between 82 and 90 degrees Fahrenheit, with a warmer basking spot (up to about 95 or 97 degrees Fahrenheit). Nighttime temperatures can be lowered to around 70 or 75 degrees Fahrenheit. A thermal gradient is recommended.