Home range, sleeping site use, and band fissioning in hamadryas baboons: Improved estimates using GPS collars.

Variation in spatial and temporal distribution of resources drives animal movement patterns. Links between ecology and behavior are particularly salient for the multilevel society of hamadryas baboons, in which social units cleave and coalesce over time in response to ecological factors. Here, we used data from GPS collars to estimate home range size and assess temporal patterns of sleeping site use in a band of hamadryas baboons in Awash National Park, Ethiopia.

Female "dispersal" in hamadryas baboons: transfer among social units in a multilevel society.

Unlike most cercopithecines, hamadryas baboons (Papio hamadryas hamadryas) are characterized by female-biased dispersal. To clarify this pattern within the context of their hierarchical social system (comprising one-male units, clans, bands, and troops), we report here 7 years of data on female transfers among social units in wild hamadryas baboons in Ethiopia. Female tenure in one-male units (OMUs) ranged from 1 to 2,556 days (N = 208) and survival analysis revealed a median tenure length of 1,217 days (40 months).

Infant mortality after takeovers in wild Ethiopian hamadryas baboons.

In this work we report the first observational evidence of infanticide in wild hamadryas baboons. The study group inhabits the lowlands of the northern Rift Valley in Ethiopia and has been under observation for over 1,200 hr, on and off, since October 1996. Here we report observations from August and September 2002 of the consequences of two takeovers of known females with black infants.