Movements and prey of a female Cheetah

Movements and prey of a female Cheetah in the context of the predator hierarchy

Chris Roche was the winner of the prize for the best field project in the second edition of CC Africa's Ecological Journal published in 2000. Here, in the second of a series highlighting field projects conducted by rangers at various CC Africa lodges across Africa, we present a shortened version of his work on Cheetah at Ngala during 1998 and 1999.

The predator hierarchy

All African predators can, with some predictability, be fitted into a predator hierarchy that owes as much to physical size as to sociability and strength of numbers. With regard to the larger predators such as Lion, Spotted Hyena, Leopard and Wild Dog, Cheetah fit in at the bottom and are dominated by all these larger and (sometimes) more sociable predators. Lion and Spotted Hyena have an especially negative impact on Cheetah, stealing carcasses and accounting for the high mortality of cubs. Cheetah therefore thrive in areas where they are absent or occur at low densities and struggle in areas where they are common. All these other species occur at Ngala and, with the exception of Wild Dog, can be considered common. As a result Cheetah occur only irregularly. Between October 1998 and December 1999 however, as many as 17 different Cheetah made consistent use of the area and a specific female and her three sub-adults took up residence, providing excellent viewing as they became increasingly relaxed.

Home range, activity patterns and diet - Avoiding conflict and staying alive

Over the 14-month period of the study, Cheetah were located on almost 100 days and showed a strong preference for short grass clearings with high concentrations of Impala. These areas overlapped with the core territories of two resident and stable Lion prides and would not normally have been utilised by the Cheetah. However, immediately prior to the appearance of the Cheetah in the area, these prides had been dispersed by the arrival of five new male Lions who proceeded to scatter all resident prides and then themselves roam widely in pursuit of them. The highly vocal nature of these new males allowed the Cheetah to take advantage of temporary 'Lion vacuums' which occurred in the prime areas of game concentration, by locating themselves away from Lion activity. At the same time the Cheetah were typically active by day compared with their main competitors such as the nocturnal Lion, Spotted Hyena and Leopard.

These male Lions would return to the central area on a regular basis, to consolidate their dominance over the territory. On these occasions, the Cheetah would move into less favourable adjacent areas before moving back in when the Lions had gone. Once the males managed to kill the existing Lion cubs, bringing the Lionesses back into oestrus in the well-documented practice of infanticide however, stability returned to the Lion dynamics and the original territories were once again reoccupied with new cubs being born. At this stage the Cheetah moved to the fringes of the Lion territories, enjoying only occasional forays into their previously productive hunting grounds, before the cubs became independent and dispersed into new areas.

Within their core range over this period of the study, Cheetah exhibited a very strong predilection for Impala as a prey species with more than 96% of the prey record being comprised of this species. Adult and sub-adult Impala ewes were most favoured with an apparent focus on pregnant ewes prior to the lambing season and thereafter newborn lambs. Carcasses of all sizes, from adult rams to newborn lambs, were lost to Lion, Spotted Hyena, Leopard and Wild Dog, with this kleptoparasitism no doubt playing an important role in home range and the selection of prey of Impala size or smaller, such as Steenbuck.

Conclusions

The detailed knowledge of the activities of all key predator species in the Ngala concession enabled an analysis of the most vulnerable of these - the Cheetah - in relation to its main threat - the Lion. Results of the study would seem to indicate that in the South African lowveld, female Cheetah use such large home ranges in order to provide buffer areas for hunting and day-to-day existence during times when they avoid key areas occupied by Lion. They are able to do this by orientating their movements to the vocalisations of Lions and, using senses such as hearing and smell, no doubt have an intricate understanding of not only Lion, but also Spotted Hyena, Leopard and Wild Dog dynamics within the areas in which they forage. Despite this, however, Cheetah are extremely vulnerable on kills and in this study the loss of almost a quarter of kills to more powerful predators provides a stark reminder of the pros and cons of hunting in productive areas that generally support high densities of the predator guild.

- Chris Roche -

Posted: Mammals by CC Africa, Date: 21 November 2006