Introduction
The few remaining elephants that continue to survive in the Knysna forest are the World’s most southerly elephants, and represent just a small fraction of the estimated 10,000 elephants that resided in the Cape region prior to European settlement in 1650 (Hall-Martin 1992). The decline of the Knysna elephants has occurred over many years and their decline has been attributed largely to hunting practices.
By 1876 an estimated 400-500 elephants remained in this area and these elephants were under heavy pressure from hunters (Phillips 1925). By 1908 only 20 individuals remained and these elephants were declared Royal Game (Kinloch 1968). In 1970 the population stood at 11 individuals and the continued decline was attributed to illegal hunting (Carter 1970). However, it has also been suggested that inadequate forest forage resulting in poor reproductive success caused a population crash in the 70s (Vermeulen 2000).
Knysna elephants & Forest habitat
Seydack et al. (2000) suggest that the decline of the Knysna elephants is attributable to the low nutrient/carbon ratios in the diet available to them, having been confined to a predominantly forest environment due to residential and agricultural development in the area. The low nutrient/carbon ratios are thought to result in low metabolic turnover rates and thus reproductive rates that are too low to offset mortalities (Seydack et al. 2000).
Prior to the increase in residential and agricultural development, seven to eight decades ago, both source and sink populations of elephants existed within the Southern Cape (Seydack et al. 2000).
In terms of habitat patches, source patches can be defined as “productive sites that generate a seasonal supply of migrants to other patch locations” and sink patches can be defined as “unproductive sites that only receive migrants” (Hanski & Gaggiotti 2004).
In the case of the Knysna elephants, the source population occupied more open vegetation types, whereas the sink populations resided primarily in the forest and were sustained by immigration from source populations (Seydack et al. 2000). Based upon this model, Seydack et al. (2000) suggest that the Knysna elephants represent a remnant sink population.
The Wildlife and Environment Society of South Africa (WESSA) have a similar view on the Knysna elephants. However whereas Seydack et al. (2000) suggest that the Knysna elephants are a remnant sink population that cannot persist due to the demise of the source populations; WESSA suggest that the Knysna elephants have been forced into the forest due to human encroachment.
WESSA state that “In general, the indigenous forest, fynbos and exotic plantation areas to which the elephants are limited by human activity are nutritionally poor. Nutritionally superior areas, from which the elephants are presently excluded, exist between Mosselbay and George. It is thus most likely that the Knysna elephants are a relict population forced into unsuitable habitats by human encroachment. If this is the case, then the reintroduction of more elephants will only postpone the extinction of this subpopulation.” The statement also adds that “If, however, reintroduced elephants do manage to increase in numbers it is most likely that their impact on the largest and best-conserved indigenous evergreen forest in southern Africa could be substantial, and culling would need to be instituted” (WESSA Policy Statement 2001).
1994 introduction of elephants
In 1994 an attempt was made to supplement the Knysna elephant population by introducing 3 young female elephants from Kruger NP. The hope was that these introduced elephants would join up with what was believed to be the only remaining elephant, an elderly matriarch in the forest. However, one of the elephants died on release and the other two elephants preferred to spend the majority of their time in the more open fynbos habitat. In 1999 conservation officials decided to move the introduced elephants instead to Shamwari Game Reserve (Seydack et al. 2000, Milewki 2002).
Conclusion
Both the suggestions of Seydack et al. (2000) and those of The Wildlife and Environment Society of South Africa (WESSA Policy Statement 2001) imply that to re-introduce elephants into the forest itself may not be feasible due to the nutritionally poor habitat resulting in low reproductive rates.
The 1994 re-introduction attempt also indicates that even if elephants were to be introduced into the forest, they wouldn’t necessarily be inclined to stay there.
However, there is one concept that could be a feasible way of re-introducing a sustainable population of elephants not to the Knysna Forest, but to the Garden Route area in general; and that is the proposal of an Eden to Addo corridor.
Eden to Addo Corridor
In simple terms a conservation corridor is a strip of land joining two protected areas. Conservationists have come to realise that simply creating isolated protected areas is not sufficient to protect the complex processes required for proper ecological functioning. A conservation corridor allows for freedom of physical movement and freedom to exchange genetic material; both of which are vital for the survival of organisms.
The dream is to create such a corridor which would start in Plettenberg Bay and radiate out until the Eden municipality is linked to Addo National Park. The corridor would comprise a zig-zagged stretch of land that unites private landowners, conservation authorities and the state. This corridor would connect the existing three mega-reserves of the area – Garden Route Mega Reserve, Baviaanskloof Mega Reserve and Addo Elephant National Park.
Most excitingly, in theory this conservation corridor could re-establish ancient elephant migration paths across the Cape....
(Eden to Addo Corridor Initiative)
References
Carter, B. (1970) ‘Knysna Elephant Survey: February 1969 – January 1970.’ Report to the Wild Life Protection and Conservation Society of South Africa, Eastern Province Branch, Port Elizabeth, South Africa.
Eden to Addo Corridor Initiative (2007). Available at:http://www.edentoaddo.co.za/about.html. Accessed: 15 November 2010.
Hall-Martin, A.J. (1992) ‘Distribution and Status of the African elephantLoxodonta africana in South Africa 1652-1992.’ Koedoe. Vol. 35, pp. 35-68.
Hanski, I., Gaggiotti, O.E. eds. (2004) ‘Ecology, genetics and evolution of metapopulations.’ Burlington, MA: Elsevier Academic Press. ISBN 0-12-323448-4
Kinloch, B. (1968) ‘The elephants of Knysna.’ African Wildlife. Vol. 22, pp. 185-190.
Phillips, J.F.V. (1925) ‘The Knysna elephants: a brief note on their history and habits’ South African Journal of Science. Vol. 22, pp. 287-293.
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