In African semi-arid savannas livestock production frequently dominate
s human activity, but it has been claimed that wildlife ranching can b
e more profitable than extensive beef production. Traditional accounti
ng methods generally exclude the biological costs of stocking effects
on rangeland productivity. This paper presents a framework for evaluat
ing overstocking effects on the financial profits (based on market pri
ces) and economic profits (estimated from the opportunity costs of inp
uts and outputs) of alternative range-based animal production systems.
The method was applied to 50 commercial cattle, wildlife, and mixed r
anches in the Zimbabwe Midlands using 1989/90 data. Level of overstock
ing was estimated from positive differences between grazer stocking ra
te and rangeland carrying capacity, which was predicted from long-term
mean annual rainfall. Since it is generally impossible to accurately
quantify stocking effects on rangeland productivity, and thus to confi
dently evaluate overstocking costs, values ranging from Z$0.00 to Z$0.
50 kg(-1) ha(-1) overstocking were used. The resulting range of costs
were subtracted from financial and economic profits. Cattle ranches we
re significantly overstocked while mixed and wildlife ranches were not
. Thus cattle ranch profits decreased more rapidly with increasing sim
ulated overstocking cost. In other words, with increasing sensitivity
to overstocking, wildlife and mixed ranches had a higher probability o
f remaining financially and economically profitable than did cattle ra
nches.