Crop-raiding 79Concluding this section we can say that the Budongo chimpanzees do not appear to
hunt frequently despite a relatively high density of potential prey (forest monkeys of all
three species occur at high densities in the range of the Sonso chimpanzees, Plumptre and
Reynolds 1994). The number of hunting and meat-eating episodes observed may, how-
ever, be far short of the actual number taking place because some successful hunts are
sure to have gone unnoticed by observers. This was particularly brought home to Hugh
Notman when he observed two of the Sonso males catch and kill a colobus monkey in
total silence when other chimpanzees were nearby, apparently keeping quiet about it in
order to maximize their own benefits, because they moved away from nearby chim-
panzees with their kill. This could be called ‘covert hunting’ (Newton-Fisher et al. 2002).
At other sites, hunting appears to be more frequent and the prey species may be dif-
ferent too. In Kibale, for example, the predominant species taken by chimpanzees as
prey is the red colobus monkey,Procolobus badius, which is absent from Budongo. This
species is preferred to black and white colobus monkeys which are also present at
Kibale. In Tanzania at both Gombe and Mahale (Hosaka et al. 2001), and in West Africa
at Taï Forest, red colobus monkeys are the preferred prey. It may be that their larger
group size (up to 100 in a group) is a response to chimpanzee predation, they may have
a less successful method of escaping from chimpanzees in the treetops, or they may just
taste better, but they are certainly the preferred form of meat at most other sites where
hunting has been described, 80% or more of all prey eaten being red colobus at these
sites (Hosaka et al. 2001). These and other aspects of red colobus–chimpanzee interactions
are discussed thoroughly by Stanford (1998).
Crop-raiding
The last kind of feeding behaviour I want to mention is crop-raiding. Chimpanzees are
occasionally partial to mangoes, paw-paws, maize cobs and sugar cane, all of which
are grown in the villages around the forest.
The Sonso chimpanzees do sometimes raid crops, particularly near the village of
Nyakafunjo to the south, and sometimes with disastrous results.^22 Having examined
their dung over the last 12 years, we know that they live almost entirely on forest foods.
Nevertheless crop-raiding does occur on mangoes and these days into the sugar cane
fields near the forest edge.
The Nyakafunjo chimpanzees do much more crop-raiding than their Sonso cousins.
They live much closer to people (the village people of Nyakafunjo) and a survey
(Watkins 2001, in press) found that the people of this village see chimpanzees often,
sometimes in the context of crop-raiding. We return to the subject of crop-raiding in
Chapter 10.
In this context, mention needs to be made of the Budongo Forest chimpanzees that
live outside the main forest block. Around the southern margins of the forest, where
(^22) In May 2003, while this book was being written, our fine adult male Jambo was speared to death while
crop-raiding at Nyakafunjo. A similar fate may have befallen Vernon in 1999.