Publications

Ecological change, group territoriality, and population dynamics in Serengeti Lions

Abstract:

Territorial behavior is expected to buffer populations against short-term environmental perturbations,

but we have found that group living in African lions causes a complex response to long-term

ecological change. Despite numerous gradual changes in prey availability and vegetative cover, regional
populations of Serengeti lions remained stable for 10- to 20-year periods and only shifted to new

equilibria in sudden leaps. Although gradually improving environmental conditions provided sufficient

resources to permit the subdivision of preexisting territories, regional lion populations did not expand

until short-term conditions supplied enough prey to generate large cohorts of surviving young. The

results of a simulation model show that the observed pattern of ‘‘saltatory equilibria’’ results from the

slions’ grouping behavior.

Packer, C., R. Hilborn, A. Mosser, B. Kissui, M. Borner, G. Hopcraft, J. Wilmshurst, S. Mduma, A. Sinclair. 2005. Ecological change, group territoriality, and population dynamics in Serengeti Lions.

Science. 307:390-393.

Can parks protect migratory ungulates? The case of the Serengeti wildebeest

Abstract:

The conservation of migratory species can be problematic because of their requirements for large

protected areas. We investigated this issue by examining the annual movements of the migratory

wildebeest, Connochaetes taurinus, in the 25 000 km2 Serengeti-Mara Ecosystem of Tanzania and

Kenya.We used Global Positioning System telemetry to track eight wildebeest during 1999–2000 in

relation to protected area status in different parts of the ecosystem. The collared wildebeest spent 90% of

their time within well-protected core areas. However, two sections of the wildebeest migration route – the

Ikoma Open Area and the Mara Group Ranches – currently receive limited protection and are threatened

by poaching or agriculture. Comparison of current wildebeest migration routes to those recorded during

1971–73 indicates that the western buffer zones appear to be used more extensively than in the past. This

tentative conclusion has important repercussions for management and needs further study. The current

development of community-run Wildlife Management Areas as additional buffer zones around the

Serengeti represents an important step in the conservation of this UNESCO World Heritage Site. This

study demonstrates that detailed knowledge of movement of migratory species is required to plan effective

conservation action.

Thirgood, S., A. Mosser, S. Tham, G. Hopcraft, E. Mwangomo, T. Mlengeya, M. Kilewo, J. Fryxell, A.

Sinclair and M. Borner. 2004. Can parks protect migratory ungulates? The case of the Serengeti wildebeest. Animal Conservation. 7, 113–120.