A die-off of large ungulates following a Stomoxys biting fly out-break in lowland forest, northern Republic of Congo

Understanding the role of natural die-offs or severe population declines is of significant importance to the management and conservation of large mammal populations. A die-off of bongo and other large ungulates occurred following a Stomoxys biting fly out-break in the lowland forest of the northern Republic of Congo in April-May 1997. Direct observations, remote camera surveys and monitoring within forest clearings indicated that the Stomoxys outbreak contributed to significant mortality in the bongo population and affected local distribution. Mortality was higher in adult males than in females. Male biased Stomoxys related mortality was also observed in sitatunga. Understanding of the causes and impact of such die-offs on bongo and other species are important to conservation and management planning in Central Africa.