Assessing the risks of intervention: immobilization, radio-collaring and vaccination of African wild dogs

Controversy has surrounded the role of intervention in studies of African wild dogs Lycaon pictus. Following the death or disappearance of all wild dogs under study in the Serengeti ecosystem, it was suggested that immobilization, radio-collaring or administration of rabies vaccines might have caused high mortality by compromising wild dogs' immune response to rabies virus. Planning future management and research on wild dogs and other species demands an assessment of the risks associated with such intervention. This paper critically reviews the available evidence and concludes that it is extremely unlikely that intervention contributed to the extinction of wild dogs in the Serengeti ecosystem. A more likely scenario is that vaccination failed to protect wild dogs exposed to rabies virus. Radio-collaring is an important component of wild dog research; hence, the benefits of immobilization appear to outweigh the risks, as long as (i) research is orientated towards wild dog conservation, (ii) radio-collaring is followed up by efficient monitoring, (iii) the number of animals immobilized is kept to the minimum necessary to maintain scientific rigour, and (iv) full data on disease and genetics are collected from all immobilized animals. By contrast, rabies vaccination currently seems to confer few benefits, at least when a single dose of vaccine is given. Further research, on captive animals, is in progress to establish more effective protocols, and to assess the role that vaccination might play in future management of wild dog populations.