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Author

Tinyiko C. Shivambu

Other affiliations: University of Pretoria
Bio: Tinyiko C. Shivambu is an academic researcher from University of KwaZulu-Natal. The author has contributed to research in topics: Geography & Parakeet. The author has an hindex of 4, co-authored 11 publications receiving 32 citations. Previous affiliations of Tinyiko C. Shivambu include University of Pretoria.

Papers
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Journal ArticleDOI
TL;DR: All the introduced invasive bird species in South Africa were climatically suitable to South Africa and Passer domesticus, Sturnus vulgaris, and Anas platyrhynchos each had relatively large climatic suitability distributions, which need to be incorporated in decision-making and eradication plans.
Abstract: Globally, various avian species have been introduced accidentally and deliberately by humans through different pathways. Some of these species were able to establish, multiply, and become invasive. In this study, we identified areas that are climatically suitable for seven introduced invasive bird species and assessed the environmental and socio-economic impacts associated with the selected bird species in South Africa. We used present distribution records to predict potential climatic suitability distributions and used the Generic Impact Scoring Scheme to assess the impacts associated with seven invasive bird species in South Africa. We found that all the seven species were climatically suitable to South Africa and Passer domesticus, Sturnus vulgaris, and Anas platyrhynchos each had relatively large climatic suitability distributions. The climatic suitability for all the species was within their occurrence ranges in and outside South Africa. For impact assessments, we found that all seven selected species had impacts, with A. platyrhynchos, Acridotheres tristis, Columba livia, and Psittacula krameri having the highest overall impacts respectively. The socio-economic impact ranked higher than environmental impact for all species. The socio-economic impacts were frequently through agricultural production and human infrastructure, while the environmental impact was mostly through impacts of birds on other animals and competition. These need to be incorporated in decision-making and eradication plans for these alien invasive birds in South Africa.

16 citations

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TL;DR: This paper reviewed case studies of vertebrate species' responses to urbanisation in KwaZulu-Natal, South Africa, to determine trends and presented a novel modification to the final of three phases of the framework described by Evans et al. (2010).
Abstract: Urbanisation is rapidly transforming natural landscapes with consequences for biodiversity. Little is documented on the response of African wildlife to urbanisation. We reviewed case studies of vertebrate species' responses to urbanisation in KwaZulu-Natal, South Africa to determine trends. Connected habitat mosaics of natural and anthropogenic green spaces are critical for urban wildlife persistence. We present a novel modification to the final of three phases of the framework described by Evans et al. (2010), which documents this sequence for vertebrate species persistence, based on the perspective of our research. Species in suburbia exhibit an initial phase where behavioural and ecological flexibility, life-history traits and phenotypic plasticity either contribute to their success, or they stay at low numbers. Where successful, the next phase is a rapid increase in populations and distribution; anthropogenic food resources and alternate breeding sites are effectively exploited. The modified third phase either continues to spread, plateau or decline.

12 citations

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TL;DR: The assessment of Rose-ringed Parakeets feeding ecology may help understand their potential impact on native tree and bird species within an urban landscape and supports that parakeets are generalist-opportunistic feeders.
Abstract: The Rose-ringed Parakeet Psittacula krameri is one of the world’s commonest invasive bird species and has established in the South African urban landscapes. However, relatively little is known about the feeding biology of parakeets here. We surveyed areas in eThekwini Municipality, Durban, South Africa, to determine their feeding sites and the related land-use types. Patterns of the association were explored using Correspondence Analysis to determine parakeets’ diet across seasons and interaction between different tree species fed on by parakeets and other bird species. Dietary items were determined visually using binoculars. We identified a total of 63 feeding sites with many in the urban built land-use cover type. The parakeets’ diet differed significantly across the seasons with spring accounting for 33% of annual food items. We identified 31 fruiting/flowering tree species fed on by the parakeets, with fleshy fruits and flowers accounting for 58% and 19%, respectively. Native tree species (63%) were mostly relied on when compared with non-native (27%). They also fed on carpenter ants Camponotus cinctellus which contributed 3% of their diet. The forest fever-berry Croton sylvaticus (fleshy fruits) and African star-chestnut Sterculia africana (flowers) were the most preferred tree species in autumn and summer. The observed number of bird species that communally fed with parakeets were significantly different across the sampled seasons. The diets for the Common Myna Acridotheres tristis and the Speckled Mousebird Colius striatus overlapped with parakeets for most tree species. Parakeets were observed actively feeding in the early mornings and late afternoons before roosting. Our study supports that parakeets are generalist-opportunistic feeders. The assessment of Rose-ringed Parakeets feeding ecology may help understand their potential impact on native tree and bird species within an urban landscape.

10 citations

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TL;DR: A large proportion of the known tarantula species are traded in South Africa and must be included in management and risk assessments to avoid potential invasions.
Abstract: Many alien species have been introduced around the world as part of the pet trade, and some have escaped captivity and become invasive. In South Africa, many species of tarantula (Theraphosidae) ar...

10 citations

Journal ArticleDOI
12 Aug 2020
TL;DR: The Generic Impact Scoring System was used to assess the potential effects associated with 24 non-native small mammal species sold in the South African pet trade and found no statistically significant difference between the overall environmental and socio-economic impact scores.
Abstract: The pet trade is one of the most important pathways by which small mammals are introduced to non-native areas. To prevent the introduction and invasion of non-native pets, an impact assessment protocol is useful in understanding which pets might have potential negative impacts should they escape or be released from captivity. In this study, we used the Generic Impact Scoring System (GISS) to assess the potential effects associated with 24 non-native small mammal species sold in the South African pet trade. European rabbits Oryctolagus cuniculus, house mice Mus musculus, Norwegian rats Rattus norvegicus and eastern grey squirrels Sciurus carolinensis had the highest potential impacts for both socio-economic and environmental categories. We found no statistically significant difference between the overall environmental and socio-economic impact scores. Impacts on agricultural and animal production (livestock) were the main mechanisms in the socio-economic category, while the impacts on animals (predation), competition and hybridisation prevailed for environmental impacts. The non-native mammal pet species with high impacts should be strictly regulated to prevent the potential impacts and establishment of feral populations in South Africa.

8 citations


Cited by
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01 Jul 2011
TL;DR: This article proposed a unified framework for biological invasions that reconciles and integrates the key features of the most commonly used invasion frameworks into a single conceptual model that can be applied to all human-mediated invasions.
Abstract: There has been a dramatic growth in research on biological invasions over the past 20 years, but a mature understanding of the field has been hampered because invasion biologists concerned with different taxa and different environments have largely adopted different model frameworks for the invasion process, resulting in a confusing range of concepts, terms and definitions. In this review, we propose a unified framework for biological invasions that reconciles and integrates the key features of the most commonly used invasion frameworks into a single conceptual model that can be applied to all human-mediated invasions. The unified framework combines previous stage-based and barrier models, and provides a terminology and categorisation for populations at different points in the invasion process.

338 citations

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TL;DR: In this article , the authors present an overview of the global spatiotemporal distribution of avian biodiversity, changes in our knowledge of that biodiversity, and the extent to which it is imperilled.
Abstract: We present an overview of the global spatiotemporal distribution of avian biodiversity, changes in our knowledge of that biodiversity, and the extent to which it is imperilled. Birds are probably the most completely inventoried large taxonomic class of organisms, permitting a uniquely detailed understanding of how the Anthropocene has shaped their distributions and conservation status in space and time. We summarize the threats driving changes in bird species richness and abundance, highlighting the increasingly synergistic interactions between threats such as habitat loss, climate change, and overexploitation. Many metrics of avian biodiversity are exhibiting globally consistent negative trends, with the International Union for Conservation of Nature's Red List Index showing a steady deterioration in the conservation status of the global avifauna over the past three decades. We identify key measures to counter this loss of avian biodiversity and associated ecosystem services, which will necessitate increased consideration of the social context of bird conservation interventions in order to deliver positive transformative change for nature. Expected final online publication date for the Annual Review of Environment and Resources, Volume 47 is October 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

37 citations

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TL;DR: The Pingtan Island of China and the Durban city of South Africa were chosen as case study area for a comparative study of different scales to ensure regional ecological security and stability to achieve sustainable development.
Abstract: The unprecedented regional urbanization has brought great pressure on the ecological environment. Building an ecological security pattern and guide regional land and space development is an important technique to ensure regional ecological security and stability to achieve sustainable development. In this study, the Pingtan Island of China and the Durban city of South Africa were chosen as case study area for a comparative study of different scales. The importance of ecosystem services and ecological sensitivity were evaluated, respectively. The core area of landscape which is vital for ecological function maintenance was extracted by morphological spatial pattern analysis (MSPA) and landscape connectivity analysis. Furthermore, the ecological sources were determined by combining the results of ecological protection redline delimitation and core area landscape extraction. The potential ecological corridors were identified based on the minimum cumulative resistance model, and the ecological security pattern of study areas was constructed. The results showed that the ecological protection redline areas of Pingtan and Durban were 42.78 km2 and 389.07 km2, respectively, which were mainly distributed in mountainous areas with good habitat quality. Pingtan ecological security pattern is composed of 15 ecological sources, 16 ecological corridors, 10 stepping stone patches and 15 ecological obstacle points. The total length of corridors is 112.23 km, which is radially distributed in the form of “one ring, three belts”. The ecological security pattern of Durban is composed of 15 ecological sources, 17 ecological corridors, 11 stepping stone patches and 18 ecological obstacle points. The total length of corridors is 274.25 km, which is radially distributed in the form of “two rings and three belts”. The research results can provide an important reference for the land space construction planning and ecological restoration projects in Pingtan and Durban.

19 citations

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TL;DR: This paper investigated the conservation potential of dry grassland fragments in the Great Hungarian Plain, i.e. patch-like habitats on ancient burial mounds and linear-shaped habitats in verges, and compared them to continuous grasslands.
Abstract: In intensively used landscapes biodiversity is often restricted to fragmented habitats. Exploring the biodiversity potential of habitat fragments is essential in order to reveal their complementary role in maintaining landscape-scale biodiversity. We investigated the conservation potential of dry grassland fragments in the Great Hungarian Plain, i.e. patch-like habitats on ancient burial mounds and linear-shaped habitats in verges, and compared them to continuous grasslands. We focused on plant taxonomic diversity, species richness of specialists, generalists and weeds, and the phylogenetic diversity conserved in the habitats. Verges meshing the landscape are characterised by a small core area and high level of disturbance. Their species pool was more similar to grasslands than mounds due to the lack of dispersal limitations. They held high species richness of weeds and generalists and only few specialists. Verges preserved only a small proportion of the evolutionary history of specialists, which were evenly distributed between the clades. Isolated mounds are characterised by a small area, a high level of environmental heterogeneity, and a low level of disturbance. Steep slopes of species accumulation curves suggest that high environmental heterogeneity likely contributes to the high species richness of specialists on mounds. Mounds preserved the same amount of phylogenetic diversity represented by the branch-lengths as grasslands. Abundance-weighted evolutionary distinctiveness of specialists was more clustered in these habitats due to the special habitat conditions. For the protection of specialists in transformed landscapes it is essential to focus efforts on preserving both patch-like and linear grassland fragments containing additional components of biodiversity.

17 citations

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TL;DR: This paper explored global patterns of trade in the arachnids, and detected 1,264 species from 66 families and 371 genera in trade, with 67% coming directly from the wild, and up to 99% of individuals in some genera.
Abstract: Abstract Wildlife trade is a major driver of biodiversity loss, yet whilst the impacts of trade in some species are relatively well-known, some taxa, such as many invertebrates are often overlooked. Here we explore global patterns of trade in the arachnids, and detected 1,264 species from 66 families and 371 genera in trade. Trade in these groups exceeds millions of individuals, with 67% coming directly from the wild, and up to 99% of individuals in some genera. For popular taxa, such as tarantulas up to 50% are in trade, including 25% of species described since 2000. CITES only covers 30 (2%) of the species potentially traded. We mapped the percentage and number of species native to each country in trade. To enable sustainable trade, better data on species distributions and better conservation status assessments are needed. The disparity between trade data sources highlights the need to expand monitoring if impacts on wild populations are to be accurately gauged and the impacts of trade minimised.

15 citations