Body size, age, and growth were studied in samples of Nile monitor lizards from variably exploited populations. One sample originated from the central Niger delta, in Mali, and the other two from Lake Chad. Snout–vent length, mean age, and longevity were reduced in the most exploited animals. These exhibited a characteristic pattern of somatic growth: size increased up to an age of 30 months and then dropped steeply to a negligible level after 54 months. Conversely, in the less exploited populations, initial growth was slower but remained at a sustained level within the limits of individual longevity. With reference to available data on sexual maturation and reproductive output in harvested Varanus niloticus, these results suggest that rapid growth and early sexual maturity both contribute to a demographic accommodation in exploited monitor populations.