Post‐natal growth of elephants Loxodonta africana in Etosha National Park, Namibia

Abstract

Post‐natal growth in the African elephant (Loxodonta africana) was described using three alternative mathematical models, and two age estimation schedules. Von Bertalanffy, Gompertz and Logistic equations all provided adequate models of post‐natal growth in a species for which age estimation methods are largely unsubstantiated. Gompertz and Logistic models overestimated pre‐weaning growth and underestimated adult size. Self‐accelerating growth is of short duration (one and three years in females and males, respectively), and we found no evidence of a secondary growth spurt in males. Males, nevertheless, continue to grow throughout their lifespan, while females reach asymptotic size at the age of 35–40 years. We found no evidence of differences in growth rate of males and females up to 10 years, and there does not seem to be differential investment in male and female offspring. Growth rates of captive elephants differ substantially from all wild populations studied and may not serve as adequate references for the revision of existing age estimation schedules.