Conserve - Explore - Experience CEDERBERG NATURE RESERVE Suggested citation Turner, A. A. (ed.) 2012. Western Cape Province State of Biodiversity 2012. CapeNature Scientific Services, Stellenbosch. ISBN: 978-0-621-41407-3 Birss, C. and Palmer, N. G. 2012. Mammals in: Turner, A. A. (ed). Western Cape Province Satate of Biodiversity 2012. CapeNature Scientific Services, Stellenbosch. ISBN: 978-0-621-41407-3 INDEX Introduction Pg Protected areas and biodiversity 5 1 mainstreaming 2 Freshwater ecosystems 23 3 Estuarine ecosystems 53 4 Freshwater fishes 67 5 Amphibians 87 6 Reptiles 103 7 Avifauna 119 8 Mammals 149 9 Arthropods 169 10 Plants and Vegetation 177 ISBN: 978-0-621-41407-3 Western Cape Province State of Biodiversity 2012 Introduction A.A. Turner Scientific Services, CapeNature Biodiversity Biodiversity is a broad concept that incorporates all the variation that is present in life, from the genetic differences between individuals to the differences between biomes such as forest and succulent Karoo. The intrinsic value of this biodiversity is substantial but there is much more value apart from the intrinsic value. This variation houses and facilitates a multitude of ecosystem services such as the provision of clean water, pollination, flood attenuation, provision of oxygen and many others that sustain life on this planet. Healthy ecosystems underpin many aspects of human well-being (Millennium Ecosystem Assessment, 2005). It is important for this understanding, that the natural environment is critical for human survival and well-being, to gain greater awareness. This is required to move away from the erroneous but persistent view that conservation and human well-being are alternative choices. Biodiversity reaches extraordinary heights in the Western Cape Province (WCP) primarily due to the more than 13,000 plant species of the Cape Floristic Region (CFR) which is almost completely contained within the WCP borders. New plant and animal species continue to be described in the WCP and there is a growing recognition that there is more animal diversity represented in the province than previously thought (see chapters 4, 5 and 8). The very high levels of diversity are thought to have arisen due to the long evolutionary history of the WCP and the topographical and edaphic (soil) diversity of the province (e.g. Cowling et al. 2009, Linder et al. 2010). This, coupled with the relatively stable climatic conditions, has allowed local populations of plants and animals to diversify and persist through evolutionary time leading to the current situation where there are many species distributed across the province’s varied landscapes. As a result of this mode of evolution, many of these species have small and restricted ranges which has led to the province having very high numbers of endemic species. These species are dependent on this province’s conservation bodies for their conservation. Another effect of this evolutionary pattern is that many of these species are likely to be adapted to local environmental conditions and this may occur at very fine spatial scales so that the number, and extent, of suitable habitats may be very limited which limits management options. This may have knock-on management effects such as when animals or plants are moved from one area to another, the chances are good in the WCP that this may interfere with the results of many (often in the order of millions or tens of millions) years of evolution. Biodiversity is in constant flux and as custodians of a remarkable wealth of biodiversity in the WCP, it is incumbent upon CapeNature to take stock of the current status, compare changes over time to assess trends and plan actions to address upcoming conservation challenges. Changes in the state of biodiversity must be evaluated against a backdrop of an expanding human populace: the percentage increase in the WCP population between 2001 and 2007 was proportionately the largest in South Africa at 16.7% (Statistics SA 2007) and the population has continued to grow as the AFRICAN BLACK OYSTERCATCHERS WCP share of the country’s population rose from 10.2% in 2007 to 10.45% in 2011 (Statistics SA 2011) with justifiable Introduction 1 STATE OF BIODIVERSITY 2012 expectations of an improved standard of living which create increase in the near future” (Millennium Ecosystem Assessment, additional economic demands. In addition there are large-scale 2005). Five years later it was stated in the Global Biodiversity changes in the biophysical realm such as anthropogenic climate Outlook 3 that “The five principal pressures directly driving change (IPCC 2007) which will impact on where, how and to biodiversity loss (habitat change, overexploitation, pollution, what degree conservation measures are effective in the long invasive alien species and climate change) are either constant or term (see DEA&DP 2008). All these changes make maintaining increasing in intensity” biodiversity and ecosystem functioning an increasingly complex (Secretariat of the Convention on Biological Diversity, 2010). and challenging task. Within South Africa, the situation is mixed: some progress CapeNature has produced State of Biodiversity Reports and we has been made with establishment of a suite of bioregional compile these reports in response to: programmes with a strong focus on the ecosystem approach and on mainstreaming, development of tools for mainstreaming A. Legislative context: South Africa has a well-developed suite biodiversity in land‐use planning and environmental assessment; of environmental legislation that entrenches environmental business and biodiversity initiatives with key production protection and wise stewardship from the Constitution of the sectors; establishment of stewardship programmes to secure Republic of South Africa (section 24 of the Bill of Rights) through protected area expansion on private land; and most recently national legislation – National Environmental Act (NEMA) the implementation of fiscal incentives to support conservation and the Biodiversity Act (NEMBA) to Provincial legislation – on private land (South Africa’s Fourth National Report to the the Western Cape Nature Conservation Board Ordinance. Convention on Biological Diversity, 2009). However, there The NEMBA requires reporting on the state of biodiversity are also indications that the status of threatened species is at a national level. Provincial level reporting should facilitate declining and biodiversity and ecosystem health continues the national reporting. In line with the national legislation, to decline as key drivers of change (land‐use change, climate CapeNature, as the agency responsible for biodiversity change and alien invasive species) show no sign of decreasing conservation in the Western Cape Province, is developing (South Africa’s Fourth National Report to the Convention on a provincial Biodiversity Bill that will implement biodiversity Biological Diversity, 2009). The same report also lists human monitoring at a provincial level. This will also align with the capacity is a key constraint, and shortfalls in financial resources country’s obligation under Articles 6 and 7 of the Convention on present a challenge (South Africa’s Fourth National Report to Biological Diversity (CBD). the Convention on Biological Diversity, 2009). The challenge of capacity is now being dealt with by GreenMatter – a biodiversity The Department of Environmental Affairs and Tourism compiled sector skills capacity enhancement programme. a National Biodiversity Strategy and Action Plan (NBSAP) for (see http://www.greenmatter.co.za/). South Africa to guide implementation of the CBD (DEAT 2005). The WCP State of Biodiversity Report specifically addresses Major threats indicators listed under Strategic Objective 2.5 although it touches on several other objectives (e.g. 2.2., 3.3, 5.2). Invasive alien species The South African Department of Environmental Affairs has Invasive alien species may cause myriad problems for the natural set 12 outcomes as a key focus of work between 2010 and environment and society alike. The effects caused by invasive 2014 (DEA undated). Of direct relevance to the conservation alien plant species are reviewed by Le Maitre et al. (2011). of biodiversity is Outcome 10: that environmental assets and Although much attention has been and continues to be devoted natural resources are protected and continually enhanced. to invasive alien plant species, there are some intense pressures Within Outcome 10, outputs 1: enhanced quality and quantity developing from the impact of invasive alien animals. Invasive of water resources, 3: sustainable environmental management alien plants remain an extensive problem in the WCP despite and 4: protected biodiversity are addressed in chapters 2, 3 and a massive effort from CapeNature and Working for Water 1 respectively. The WCP’s Strategic Objective 7: Mainstreaming (see chapter 10). The extent and intensity of the problem is sustainability and optimising resource-use efficiency is addressed represented at a quarter degree scale in Le Maitre et al’s 2011 in chapter 1. Figure 14.1 which clearly shows the large number of invasive alien plant species in the WCP. The suite of IAS is also growing B. To provide an opportunity to assess trends in the conservation status of the WCP species and the associated and presenting new challenges (see Chapter 10). Responses to conservation management; and this situation will require an expansion of the tools and spatial scale of the operations we employ to tackle this problem.