U.S. Department of Agriculture: Animal and Plant Health Inspection Service


Document Type


Date of this Version

October 2006


Copyright 2006 The Authors. Journal compilation Copyright 2006 Blackwell Publishing Ltd, Afr. J. Ecol. Permission to use.


In many places in Africa, constraints in human, financial and physical resources are common problems that limit the effectiveness of wildlife researchers and managers. In an attempt to identify a useful tool for monitoring African wildlife populations, we tested a passive tracking index (PTI) methodology on a unique wildlife resource area in the Lower Omo Valley, Ethiopia. The methodology had previously proved valuable for monitoring a wide variety of wildlife species, including ungulates and carnivores in North America and Australia. Two ungulates (lesser kudu and dikdik), a carnivore (hyena), a primate (baboon), and a ground foraging bird (guineafowl) were simultaneously indexed. In addition, single observations were recorded for genet, serval and caracal. The species indexed also represent the broad needs for monitoring wildlife. The mammal species are of economic importance to the region through sport hunting. Two of the species, hyenas and baboons, potentially conflict with human agricultural interests through depredations on livestock and crop production. Anthrax periodically decimates the wildlife in the Lower Omo Valley, Ethiopia, but losses of many species are difficult to observe or quantitatively document. The PTI is a simple-to-apply, easy-to- calculate means to quantify simultaneously population trends for multiple species, and particularly applicable to sustainable harvest by sport hunting, human–wildlife conflicts, and impacts and recovery from wildlife disease.