Premium
The natural regulation of buffalo populations in East Africa: III. Population trends and mortality *
Author(s) -
SINCLAIR A. R. E.
Publication year - 1974
Publication title -
african journal of ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.499
H-Index - 54
eISSN - 1365-2028
pISSN - 0141-6707
DOI - 10.1111/j.1365-2028.1974.tb00112.x
Subject(s) - population , predation , malnutrition , demography , juvenile , biology , fertility , population growth , mortality rate , ecology , medicine , pathology , sociology
Summary Analysis is carried out on the population data obtained from censuses and estimates of fertility and recruitment for the years 1965–1972, From the analysis, adult mortality is the only detectable reduction which acts as a negative feedback on the population, and is the only one needed to regulate the population in a way similar to the observed population trends. From a frequency distribution of ages at death, an approximate composite life table is constructed. This shows that males and females have similar age‐specific mortalities until old age, but then males survive relatively better. Information on the causes of mortality indicate that the regulating adult mortality is caused in part by undernutrition, which in turn is due to food limitation rather than to social and physiological factors. Predation causes only a small part of the annual adult mortality, and its effect is swamped by other factors. Diseases play an important part as a primary factor in juvenile mortality but not in adult mortality because of the development of immunity. However, both disease and predation are important as secondary agents killing adults already weakened by moderate undernutrition. It is suggested that they play an essential role by hastening the population's response to changes in the food supply, and hence dampening oscillations that might develop in population and resource.