We present data on the pattern of births in the Drakensberg Mountain baboon
population (Papio cynocephalus ursinus). Data from five troops at two diff
erent locations reveal a seasonal bias in the distribution of births with s
ignificantly more occurring during wet months (n = 32) than during dry mont
hs (n = 5). The number of conceptions per month peaked following a number o
f consecutive high rainfall months, providing evidence for the claim that t
he proximate mechanism mediating conception timing is probably improved bod
y condition associated with increased food availability.