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Society for Conservation Biology 16th
Annual Meeting July 14-July 19 2002
co-hosted by DICE and the British Ecological Society
Abstracts for Symposium Seven
Conservation planning for the Cape Floristic
Region: systematic identification of priority areas in a globally significant ecoregion
Keynes Lecture Theatre 1
Wednesday 17th July: 10.15 - 12.15
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Details
(BLOCK CAPITALS indicate the presenting author)
09.00 - 09.45 (Plenary - Large Sports Hall)
COWLING, RICHARD and Bob Pressey. Terrestrial Ecology Research Unit, University
of Port Elizabeth, PO Box 1600, Port Elizabeth 6000, South Africa (btarmc@upe.ac.za)
(RC), and New South Wales National Parks and Wildlife Service, PO Box 402 Armidale
NSW 2350 Australia (BP)
PLANNING FOR MULTIPLE BIODIVERSITY TARGETS: A CASE STUDY FROM THE CAPE FLORISTIC
REGION
Using the principles and practices of systematic conservation planning, we produced
a plan that achieved conservation targets for biodiversity pattern and process in
the species-and endemic-rich Cape Floristic Region of South Africa. Features targeted
were: land classes; localities of Proteaceae and selected vertebrate species, comprising
reptiles, amphibians and freshwater fish; population sizes for medium- and large-sized
mammals; and six types of spatial components to represent evolutionary and ecological
processes. The plan was developed in several steps using C-Plan, a decision support
system linked to a geographical information system. First we selected spatially fixed
process components; then we selected areas required to accommodate targets for mammals;
next we selected those planning units that achieved targets for land classes and
Proteaceae and vertebrate species; and finally we selected planning units required
to conserve entire upland-lowland and macroclimatic gradients. The result was a system
of conservation areas comprising both intact and restorable habitat that would ensure
the persistence and continued diversification of the region’s biota in the face of
ongoing habitat loss and climate change. We assessed implementation priorities on
the basis of conservation value and vulnerability to habitat loss, as well as socio-economic,
political and institutional constraints.
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
The SCB2002 pages are maintained by Christine Eagle
email: C.M.Eagle@ukc.ac.uk
Conference email: scb2002@ukc.ac.uk
Last updated: 30.06.02