In 1993-4, approximately 1000 lions died in the Serengeti ecosystem from canine distemper virus.  This disease can infect most carnivore species and is spread through the air by close proximity to an infected individual.  Scientists suspect that domestic dogs from Serengeti District (bordering the northwest of the National Park) might have been the source of this outbreak.  But how could a domestic dog have spread a disease to a lion? Domestic dogs will not survive long inside the National Park and lions do not survive well in villages.  Other species probably act as intermediaries between dogs and lions in the disease transmission chain. In the 1994 epidemic for example, spotted hyenas and bat-eared foxes were infected, and species like these could then have spread the disease to lions.

A study is currently underway to investigate potential disease transmission routes among and between domestic and wild carnivores. One branch of the study aims to determine which wild carnivores interact with domestic dogs in villages nearby the National Park.  Wild carnivores are known to both predate and scavenge in the villages.  We are therefore interviewing residents to get a sense of which wild carnivores are seen around households, slaughter slabs, and trash pits.  In addition, we plan to use motion and heat activated video traps to document species presence and record interactions between wild and domestic carnivores.  We can then correlate interaction events with species abundance; for example, white-tailed mongooses, genets, and jackals are most commonly seen in Serengeti District during night transects.  Are these the same species interacting with domestic dogs?

The second branch of the study focuses on documenting interaction events among carnivores inside the Serengeti National Park.  For hyenas, jackals and lions, disease transmission among the same species can occur within social units, and between groups, for example during territorial defense, kleptoparasitism (stealing kills), or long-distance movements. Many inter-specific interactions occur when carnivores compete over food at a kill. Lions, spotted hyenas, and jackals are frequently observed at the same kill at the same time.  Disease could be spread during squabbles over food or even just by sharing the same food source.

Observations of carnivore interactions help to understand the ways in which disease could be transmitted among these wild and domestic species, and ultimately to find ways to reduce the threat of various diseases to both domestic and wild animals.