Habitat quality and the decline of an African elephant population: Implications for conservation

Population numbers of Knysna elephants Loxodonta africana africana. after h aving remained static for more than six decades, dwindled rapidly from an e stimated 10 animals in 1970 to a single surviving individual. According to an explanatory model presented, the poor reproductive performance and popul ation decline of the Knysna elephants are attributable to low nutrient/carb on ratios of the diet available to them in the predominantly forest environ ment to which they were largely confined as a result of residential and agr icultural development in the region. The low dietary N/C ratios are postula ted to result in low metabolic turnover rates and therefore, reproductive r ates too low to offset mortalities During 1994 three sub-adult female eleph ants from the Kruger National Park were translocated to the Knysna forest a rea (southern Cape, South Africa) in order to supplement the dwindling popu lation. Monitoring of habitat choice and nutritional faecal parameters of b oth the translocated and a Knysna cow elephant tend to support the postulat es of the explanatory model. The translocated elephants did not remain with the matriarch (Knysna elephant) and progressively chose to range in more o pen habitat outside of the Afromontane forest area. Analyses showed that th e diet selected by the translocated elephants had higher assimilable N/C ra tios than that of the Knysna elephant. The results of the study emphasise t he importance of clearly differentiating between sink and source habitat in conservation management.