A new assessment of the costs required to bring invasive alien plants under control in the protected area network of the Cape Floristic Region

A new assessment of the costs required to bring invasive alien plants under control in the protected area network of the Cape Floristic Region
Brian W. van Wilgen1, Jennifer M. FILL1, Johan A. Baard2, Chad Cheney3, Aurelia T. Forsyth4, Tineke Kraaij5
1Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Private Bag x1, Matieland, 7602, South Africa
2South African National Parks, Garden Route Scientific Services, P.O. Box 3542, Knysna, 6570, South Africa
3South African National Parks, Table Mountain National Park, P.O. Box 37, Constantia 7848, South Africa
4CapeNature, Scientific Services, Private Bag X5014, Stellenbosch, 7599, South Africa
5Nelson Mandela Metropolitan University, School of Natural Resource Management-Nature Conservation, Private Bag X6531, George, 6530, South Africa

Fynbos vegetation is relatively well represented in protected areas of the Cape Floristic Region. However, these protected areas are under serious threat from invasive alien plants, especially woody genera such as Pinus, Hakea and Acacia. Although a large amount of money is being spent on control in these areas, there are concerns that current approaches are failing to reduce the problem. To find effective solutions, it is necessary to more accurately estimate the extent of the problem within protected areas, and the effectiveness of current control operations. This paper outlines a joint initiative by the Centre for Invasion Biology, SANParks and CapeNature to assess the situation in a comprehensive manner, and to suggest changes to current approaches that will be needed to secure the conservation of this unique ecosystem within a network of protected areas. The objectives of this paper include (i) an assessment of the magnitude of the invasive alien plant problem in fynbos protected areas; (ii) an estimation of resources needed to bring the problem under control; (iii) formulation of best management practices; (iv) an assessment of current practice against best practices; and (v) recommendations to improve future implementation of control programmes. We present data on the first two objectives, based on alien plant distribution mapping by CapeNature and SANParks, and cost estimates derived from Working for Water’s norms and standards of invasive alien plant clearing. We suggest that the current state of invasion and the projected future costs call for strategic management and allocation of resources.