Does fencing reduce the carrying capacity for populations of large herbivores

摘要: The population size of migratory species like wildebeest (Connochaetes taurinus Burchell 1823) and zebra (Equus burchelli Gray 1824) could alter following their confinement in smaller areas (Whyte & Joubert 1988), such may result the local denudation herbaceous grassland vegetation by intensive grazing subsequent general habitat degradation (Sinclair Fryxell 1985). Data collected over 25 years provided an opportunity to evaluate some factors which govern fluctuations ungulate populations a semi-arid nature reserve. Variables measured included managerial intervention through bush clearance for purpose reclaiming habitats (Patchett 1978), annual rainfall lion predation. Sabi-Sand Wildtuin (SSW) is fenced game reserve 540 km2 borders western part central region Kruger National Park (KNP) (240 50' S 310 30' E; 22,000 km2). Rainfall patterns show summer maximum that includes both reserves lies between southern 700 mm northern 550 isohyets. Average daily maximum/minimum temperatures are 300C/ 180C January 230C/80C July (Schulze 1965). terrain gently undulating composed largely catenary sequences on granitoid rocks, supporting typical communities (Venter 1986). Numbers were recorded annually SSW from 1962 ground transects followed strip method, where area sampled counting all individuals occur within whose boundaries determined visibility factor (Collinson kills (Panthera leo Linnaeus 1758), hyaena (Crocuta crocuta Erxleben 1777) or leopard pardus 1758) mortality due other (e.g. hunting old age, drought unknown reasons) monthly basis Warden, based direct sightings scouts, private