SummaryA series of censuses throughout Uganda showed that the population of marabou storks between 1970 and 1972 was of the order of 4000–5000 of which the majority were usually in Ruwenzori (formerly Queen Elizabeth) National Park. There were at least twenty breeding colonies totalling some 1300 nests.Marabous have two main types of food. Firstly, there is what might be termed ‘natural food’, such as insects and amphibia, and the poachings from carcasses. This is assumed to have been the only kind of food available to marabous until comparatively recently. The other type is food obtained as a consequence of human activity. In Uganda, the second category is now far more important than the first.The numbers of marabous at three sites are considered in relation to their food supply, and in each case it appeared that there was usually an excess of food. Against this background, consideration is given to those factors which might be limiting to the rate of increase of this species.Marabous have obviously benefited from human activity and have no doubt increased greatly in numbers as a result. Moreover, they are probably still increasing, and it appears likely that they will continue to