Browsing by Author "Shumba, Tafadzwa"

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    Effectiveness of private land conservation areas in maintaining natural land cover and biodiversity intactness
    (Elsevier, 2020) Shumba, Tafadzwa; De Vos, Alta; Biggs, Reinette, 1979-; Esler, Karen J.; Ament, Judith M.; Clements, Hayley S.
    Private land conservation areas (PLCAs) are increasingly looked to for meeting the deficit left by state-owned protected areas in reaching global conservation targets. However, despite the increasing extent and recognition of PLCAs as a complementary conservation strategy, little research has been done to quantify their effectiveness; a critical consideration if they are to be counted towards international biodiversity conservation targets. The long history of PLCAs in South Africa provides an interesting case study to address this knowledge gap. Here, we quantified the effectiveness of South African PLCAs by comparing losses in natural land cover and biodiversity intactness within PLCAs with different levels of protection to that of unprotected control points. Points within PLCAs were matched with unprotected control points to test the prediction that if PLCAs offer effective protection, losses in natural land cover and biodiversity intactness would be significantly lower within their boundaries in comparison to unprotected controls exposed to similar conditions. Consequences of natural land cover loss on biodiversity intactness were thus assessed, thus advancing standard approaches for quantifying effectiveness. Between 1990 and 2013, PLCAs lost significantly less natural land cover (3%) and biodiversity intactness (2%) than matched unprotected areas (6% and 4%, respectively). Of the natural land cover lost within PLCAs, most was converted to cultivated land. Farms can support more species than other land uses (e.g. mines), a likely explanation for why losses in biodiversity intactness were less than losses in natural land cover. Contrary to the predicted pattern, effectiveness did not increase with level of protection; informal PLCAs with no legal protection had comparable natural land cover and biodiversity intactness retention to strictly protected PLCAs, with most losses recorded among PLCAs with moderate protection. This study provides the first national-scale evidence that PLCAs can be an effective mechanism for conserving natural land cover and biodiversity intactness, which is highly relevant given current discussions around their likely long-term biodiversity conservation capacity.
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    Effectiveness of private land conservation areas in maintaining natural land cover and biodiversity intactness
    (Elsevier, 2020) Shumba, Tafadzwa; De Vos, Alta; Biggs, Reinette, 1979-; Esler, Karen J.; Ament, Judith M.; Clements, Hayley S.
    Private land conservation areas (PLCAs) are increasingly looked to for meeting the deficit left by state-owned protected areas in reaching global conservation targets. However, despite the increasing extent and recognition of PLCAs as a complementary conservation strategy, little research has been done to quantify their effectiveness; a critical consideration if they are to be counted towards international biodiversity conservation targets. The long history of PLCAs in South Africa provides an interesting case study to address this knowledge gap. Here, we quantified the effectiveness of South African PLCAs by comparing losses in natural land cover and biodiversity intactness within PLCAs with different levels of protection to that of unprotected control points. Points within PLCAs were matched with unprotected control points to test the prediction that if PLCAs offer effective protection, losses in natural land cover and biodiversity intactness would be significantly lower within their boundaries in comparison to unprotected controls exposed to similar conditions. Consequences of natural land cover loss on biodiversity intactness were thus assessed, thus advancing standard approaches for quantifying effectiveness. Between 1990 and 2013, PLCAs lost significantly less natural land cover (3%) and biodiversity intactness (2%) than matched unprotected areas (6% and 4%, respectively). Of the natural land cover lost within PLCAs, most was converted to cultivated land. Farms can support more species than other land uses (e.g. mines), a likely explanation for why losses in biodiversity intactness were less than losses in natural land cover. Contrary to the predicted pattern, effectiveness did not increase with level of protection; informal PLCAs with no legal protection had comparable natural land cover and biodiversity intactness retention to strictly protected PLCAs, with most losses recorded among PLCAs with moderate protection. This study provides the first national-scale evidence that PLCAs can be an effective mechanism for conserving natural land cover and biodiversity intactness, which is highly relevant given current discussions around their likely long-term biodiversity conservation capacity.
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    The influence of biophysical and socio-economic factors on the effectiveness of private land conservation areas in preventing natural land cover loss across South Africa
    (Elsevier B.V., 2021-06-09) Shumba, Tafadzwa; De Vos, Alta; Biggs, Reinette, 1979-; Esler, Karen J.; Clements, Hayley S.
    There is increasing interest in the potential of private land conservation areas (PLCAs) as a complementary biodiversity conservation strategy to state-owned protected areas. However, there is limited understanding of how the diverse social-ecological contexts of PLCAs influence their effectiveness in conserving biodiversity. Here, we investigated how the effectiveness of South African PLCAs in conserving biodiversity varied across social-ecological contexts, using natural land cover as a proxy. Social-ecological contexts were represented by biophysical and legal factors (distance to towns and roads, elevation, slope, terrain ruggedness, rainfall, PLCA size, distance to state-owned national parks, and presence of legal protection) and, for a subset of commercially-operated PLCAs, management factors (adopted business model, and profitability). Biophysical and legal contextual factors had low explanatory power in the best model for the nationwide analysis (n = 5121 PLCAs). For a subset of PLCAs (n = 72) we found that effectiveness depended on the strategy they adopted to generate an income, as opposed to the amount of income itself. PLCAs that attracted high volumes of visitors to small properties to view charismatic “Big 5” wildlife were less effective in conserving natural land cover than larger, more exclusive “Big 5” PLCAs and those focused on hunting. Overall, site-specific management factors were better at explaining the effectiveness of PLCAs than biophysical factors. Our findings indicate that conservation practitioners and policy makers need to recognise the diverse goals, motivations and management models of PLCAs when considering how to support them in conserving biodiversity. Future studies could explore whether these trends hold for other proxies of biodiversity conservation, beyond land cover change.
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    Quantifying the effectiveness of private land conservation areas in preventing losses of natural land cover and biodiversity intactness across South Africa
    (Stellenbosch : Stellenbosch University, 2019-12) Shumba, Tafadzwa; Clements, Hayley S.; De Vos, Alta; Biggs, Reinette, 1979-; Esler, Karen J.; Stellenbosch University. Faculty of Agrisciences. Dept. of Conservation Ecology and Entomology.
    ENGLISH ABSTRACT: Global biodiversity conservation targets cannot be achieved by relying on state-owned protected areas (PAs) alone. Private land conservation areas (PLCAs) are one potential complementary conservation strategy. However, despite their increasing extent and recognition, little is known about their effectiveness in conserving biodiversity, or how different environmental and social-ecological factors influence their effectiveness. In South Africa, a long history of conservation on PLCAs and the diverse PLCA models provide an interesting case study to address this knowledge gap. The effectiveness of PLCAs across South Africa, and factors influencing their effectiveness, were thus quantified using losses in natural land cover (NLC) and the biodiversity intactness index (BII) as proxies. NLC was based on 1990 and 2013 national land cover maps, while BII represented a measure of the percentage of major taxa that can persist in an area given different land use scenarios. Points within PLCAs were matched with unprotected control points to test the prediction that if PLCAs offer effective protection, losses in NLC and BII would be significantly lower within their boundaries in comparison to unprotected controls exposed to similar conditions. NLC and BII losses were then compared across different types of PLCAs, with the hypothesis that legally protected PLCAs would be more effective than the informal ones. Of particular interest was also how different factors influenced the effectiveness of PLCAs in preventing losses of NLC and BII. In that regard accessibility (distance to road, distance to town, elevation and slope), rainfall, age and size of PLCAs were considered as explanatory variables. There were significant differences in losses in NLC and BII between PLCAs and matched unprotected areas. PLCAs lost 3% NLC and 2% BII between 1990 and 2013, while unprotected areas lost 6% NLC and 4% BII. These findings indicate the relative effectiveness of PLCAs, and provide insight into the implications of NLC loss on biodiversity intactness, thus advancing standard approaches for quantifying PA effectiveness. There were also significant differences in losses of NLC and BII between different types of PLCAs. However, contrary to the hypothesis, effectiveness did not depend on legal protection, as informal PLCAs were relatively more effective than some of the formally protected ones. NLC and BII losses were likely to occur at points within PLCAs that were closer to towns, further from roads, with low elevation, gentle slopes, within small and old PLCAs, and with low rainfall. This supports research on state-owned PAs, in which highly accessible areas were shown to be less effective due to higher human pressure. This study provides evidence that PLCAs are relatively effective, which is highly relevant given current discussions around their inclusion towards biodiversity targets. The study also highlights how different factors influence the effectiveness of PLCAs, which has important implications on where best to establish future PLCAs and how different management strategies and policies can be better placed to facilitate biodiversity conservation within PLCAs. The study contributes to the growing body of knowledge about PLCAs as a complementary biodiversity conservation strategy worth considering, which future studies can build upon.