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10.15 - 10.30 LOMBARD, AMANDA T., Richard M. Cowling, Robert L. Pressey, Anthony G. Rebelo, and Nicholas S. Cole. Terrestrial Ecology Research Unit, Department of Zoology, University of Port Elizabeth, P.O. Box 1600, Port Elizabeth 6000, South Africa, <gemsbok@mweb.co.za> (ATL, RMC, NSC), New South Wales National Parks and Wildlife Service, P.O. Box 402, Armidale, NSW 2350, Australia (RLP), National Botanical Institute, Private Bag X7, Claremont 7735, South Africa (AGR). EFFICIENCY OF LAND CLASS VERSUS SPECIES LOCALITY DATA IN CONSERVATION PLANNING FOR THE CAPE FLORISTIC REGION Biodiversity surrogates at broad scales are often used in conservation planning to avoid the costs and time required for complete species sampling. Using Broad Habitat Units (BHUs) to represent biodiversity pattern in the Cape Floristic Region, and point species locality data for Proteas and vertebrates, we calculated measures of surrogacy. Our planning units were 4000 ha grid cells and existing reserves. After assigning conservation targets for BHUs and species, we calculated irreplaceability values for all units (irreplaceability measures the importance of that unit for the achievement of targets). Results showed that species data were not good surrogates for BHUs, because of the spatial biases in their distribution, and in sampling effort. About 10% of BHUs contained no species data. Considering currently unconserved areas only, sites totally irreplaceable for species fulfilled target requirements of only 1% of BHUs. BHUs, however, were good surrogates for species. Sites totally irreplaceable for BHUs captured 56% of currently unconserved Proteas, but only 6% of vertebrates. The Proteas missed by the BHU analysis were characterized as secure high altitude, or vulnerable low altitude, rare and limited range species. We recommend a planning strategy based on BHUs, and a subset of species (these add <1% more area). 10.30 - 10.45 RICHARDSON, DAVID M.; Mathieu Rouget; Richard M. Cowling; J. Wendy Lloyd. Institute for Plant Conservation, Botany Department, University of Cape Town, Rondebosch 7701, South Africa rich@botzoo.uct.ac.za (DMR, MR); Terrestrial Ecological Research Unit, Department of Botany, University of Port Elizabeth, P.O. Box 1600, Port Elizabeth 6000, South Africa (RMC); Agricultural Research Council, Institute for Soil, Climate and Water Geoinformatics Division, P.O. Box 12455, Die Boord 7613, South Africa (JWL) CURRENT PATTERNS OF HABITAT TRANSFORMATION AND FUTURE THREATS TO BIODIVERSITY IN TERRESTRIAL ECOSYSTEMS OF THE CAPE FLORISTIC REGION, SOUTH AFRICA Effective biodiversity conservation in the Cape Floristic Region (CFR) requires an assessment of the current situation with regard to habitat transformation, and an explicit framework for predicting the likelihood of remaining habitat (i.e. that potentially available for conservation) being transformed. We discuss the results of a detailed assessment of the current and future extent of three important factors that threaten biodiversity in the CFR: intensive agriculture (including commercial forestry plantations), urbanisation, and stands of invasive alien trees. Habitat transformation was mapped at the scale of 1:250,000, using primarily satellite imagery. We compared models derived from a rule-based approach relying on expert knowledge and a regression-tree technique, to identify other areas likely to be affected by these factors in future. Agriculture has transformed 26.7% of the CFR, and dense stands of woody alien plants and urban areas each cover 1.6%. Both models predict that at least 30% of the remaining natural vegetation could be transformed within 20 years. Threat assessment was used to derive conservation targets in subsequent stages of the conservation plan for the CFR. We discuss the importance of integrating vulnerability knowledge into conservation planning. 10.45 - 11.00 PRESSEY, BOB, Richard Cowling and Mathieu Rouget. New South Wales National Parks and Wildlife Service, PO Box 402 Armidale NSW 2350 Australia (bob. pressey@npws.nsw.gov.au) (BP), Terrestrial Ecology Research Unit, University of Port Elizabeth, PO Box 1600, Port Elizabeth 6000, South Africa (RC) and Institute for Plant Conservation, University of Cape Town, Rondebosch 7701, South Africa (MR) FORMULATING CONSERVATION TARGETS FOR BIODIVERSITY PATTERN AND PROCESS IN THE CAPE FLORISTIC REGION We identified surrogates for biodiversity pattern and process in the Cape Floristic Region of South Africa and set quantitative targets for each of them as a basis for regional conservation planning. The surrogates were broad habitat units (BHUs - mapped from physical data at 1:250,000), localities of Protea species and selected vertebrates, population sizes for medium- and large-sized mammals, and six types of spatial components to represent evolutionary and ecological processes: edaphic interfaces, upland-lowland interfaces, sand movement corridors, inter-basin riverine corridors, upland-lowland gradients, and macroclimatic gradients. BHU targets varied according to species turnover, natural rarity and threat. Targets for species localities were stratified geographically and varied according to rarity and threat. Targets for medium- and large-sized mammals varied with their dependence on the region. Each of the process components had an extant and restorable target. Extant targets for interfaces and riverine corridors were their entire lengths presently untransformed by agriculture, alien plants and urbanization. We targeted six of seven sand movement corridors because they are still functional or restorable. Targets for upland-lowland gradients were intended to join all possible pairs of upland and lowland BHUs. We set targets for macroclimatic gradients to link the major climatic and physiographic subregions. 11.00 - 11.15 Discussion 11.15 - 11.30 ROUGET, MATHIEU. Institute for Plant Conservation, University of Cape Town, Private Bag, Rondebosch 7701, South Africa (mrouget@botzoo.ac.za) THE CURRENT CONFIGURATION OF PROTECTED AREAS IN THE CAPE FLORISTIC REGION – RESERVATION BIAS AND REPRESENTATION OF BIODIVERSITY PATTERNS AND PROCESSES The formulation of a strategic plan for the conservation of terrestrial biodiversity in the Cape Floristic Region requires an objective and spatially-explicit assessment of the representativeness of major habitat categories (surrogates for biodiversity) currently under protection. The conservation status of 88 Broad Habitat Units (BHUs) was assessed in terms of prescribed conservation targets. The extent to which protected areas are able to sustain ecological and evolutionary processes was explored by assessing the extent of spatial components of these processes for all conservation areas. About 20% of the CFR is protected in some form of conservation area, mostly concentrated on sandstone substrates, and areas with high altitude and steep slopes. The reservation bias towards upland areas has seriously constrained representation of biodiversity pattern and processes. Most of the habitat diversity is poorly represented in the current conservation area system with almost 50 % of the Mountain Fynbos Complex conserved (largely exceeding its conservation target) and only 9% of the remaining primary BHUs in the lowlands. Spatial components of the ecological processes identified are poorly captured by the conservation area network although faunal and floral migration is possible in the uplands due to the strong spatial connectivity of the protected network. 11.30 - 11.45 KERLEY, GRAHAM I.H., Robert L. Pressey, Richard M. Cowling, André F. Boshoff, and Rebecca Sims-Castley. Terrestrial Ecology Research Unit, Departments of Zoology and Botany, University of Port Elizabeth, P O Box 1600, Port Elizabeth 6000, South Africa zlagik@zoo.upe.ac.za (GIHK, RMC, AFB, RS-C), New South Wales National Parks and Wildlife Service, P O Box 402, Armidale 2350, Australia (RLP). OPTIONS FOR THE CONSERVATION OF LARGE- AND MEDIUM-SIZED MAMMALS IN THE CAPE FLORISTIC REGION We assessed options for conserving the medium- and large-sized mammals in South Africa’s Cape Floristic Region (CFR). A habitat-based approach and historical records were used to determine the potential distributions of the 41 extant species, and forage production was used to estimate densities. Areas that had not been transformed through agriculture or other developments were considered available for conservation. The resulting fragments were identified as being large enough to support communities (1) including the megaherbivores, (2) excluding elephants but including black rhino, and (3) excluding megaherbivores but including at least 25 individuals of the smallest herbivore species. Smaller fragments were not considered suitable for mammal conservation. Two conservation goals were compared; first, either conserving only CFR endemics and threatened species; and second, conserving all the mammals (with some exceptions for marginally occurring species). Options for protected area systems were assessed using C-Plan, a decision support system designed for systematic conservation planning. The irreplaceability of the planning units varied only slightly under the two conservation goals. Hence the CFR endemics and threatened species effectively function as umbrella species for the remaining mammals. A suggested conservation plan focuses protective effort on a few large conservation areas. 11.45 - 12.00 PENCE, GENEVIEVE Q.K., Mark A. Botha and Jane K. Turpie. The Nature Conservancy, 14 Maine Street, Suite 401, Brunswick, Maine 04011, USA, <gpence@tnc.org> (GQKP), Cape Conservation Unit, The Botanical Society, Private Bag X10, Claremont 7735, South Africa (MAB) and Percy-FitzPatrick Institute of African Ornithology, University of Cape Town, Rondebosch 7700, South Africa (JKT). ON- AND OFF-RESERVE CONSERVATION STRATEGIES FOR THE AGULHAS PLAIN, SOUTH AFRICA: A FINANCIAL PERSPECTIVE This study investigates the practical and financial implications of alternative strategies for meeting explicit conservation goals on the Agulhas Plain, South Africa. The costs to both the state and private sector were modelled and then analysed in a Geographic Information System for three implementation scenarios. A traditional on-reserve approach could cost the state $240M in acquisition costs and an additional $401M in management costs (NPV over 30 years, 6% discount rate). A mixed management approach, where 40% of the 229 targeted properties are maintained off-reserve (in private ownership under management agreements or covenants), could eliminate 80% of acquisition costs and 51% of state-borne management costs. If it is unrealistic to expect unsolicited private participation, then a third approach offering various incentives to the private sector could still reduce total implementation costs by 37%. Additionally, property rate relief for land maintained in a natural state could save targeted landowners 20-40% in taxes, at a cost of 3.7-7.4% of the expected tax revenue. This study concludes that the prohibitive costs of realizing conservation goals on the Agulhas Plain can be curbed by the establishment of new institutions, mechanisms, and incentives for private participation in conservation. 12.00 - 12.15 Discussion |