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46
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January 2010 - February 2012
Publications
Publications (46)
The Asian Citrus Psyllid (ACP) (Diaphorina citri Kuwayama, 1908) (Hemiptera: Psyllidae) is a major citrus pest. The species has been introduced to West and East Africa, but has not yet spread to southern Africa, where it could have a devastating impact on citrus farming and livelihoods. A proactive response is key to mitigating the species’ impacts...
The Asian Citrus Psyllid (ACP) (Diaphorina citri Kuwayama, 1908) (Hemiptera: Psyllidae) is a major citrus pest. The species has been introduced to West and East Africa, but has not yet spread to southern Africa, where it could have a devastating impact on citrus farming and livelihoods. A proactive response is key to mitigating the species' impacts...
Risk analysis plays a crucial role in regulating and managing alien and invasive species but can be time-consuming and costly. Alternatively, combining invasion and impact history with species distribution models offers a cost-effective and time-efficient approach to assess invasion risk and identify species for which a comprehensive risk analysis...
Species can be both native and alien to a given administrative region. Here we present the first consolidated inventory of these ‘native-alien populations’ for South Africa, and provide an overview of the data it contains. To gather data, literature searches were performed and experts were consulted both directly and via an on-line survey. Putative...
Biological invasions are a major threat to South Africa’s biodiversity, economy, and sustainable development. This report is part of South Africa’s commitment to alleviating these impacts. It is a comprehensive national-scale assessment with contributions from 28 experts from 16 institutions. Drafts of the report were available for comment in two s...
South Africa is a mega-diverse country situated at the southern tip of Africa flanked by two unique marine systems, one cool and one warm. Species introductions to the region have also been diverse. Given the major and growing threat to biodiversity and ecosystem functioning from biological invasions, there has been significant research on this top...
Many countries define nativity at a country-level—taxa are categorised as either alien species or native species. However, there are often substantial within-country biogeographical barriers and so a taxon can be native and alien to different parts of the same country. Here, we use the term ‘native-alien populations’ as a short-hand for populations...
Biological invasions are a major threat to South Africa’s biodiversity, economy, and sustainable development. This report is a part of South Africa’s commitment to alleviating these impacts. It is a comprehensive national-scale assessment with contributions from 36 experts from 16 institutions. Drafts of the report were available for comment in two...
Supplementary material to Zengeya, T.A. & Wilson, J.R. (eds.) 2020. The status of biological invasions and their management in South Africa in 2019. Provides additional information chapter by chapter on the methods used, discussion points, and tables and figures
Biological invasions by agricultural pests can have serious negative impacts, including decreases in crop yield and economic losses. The MT-1 and MT-8 genotypes of the wheat curl mite (Aceria tosichella) (hereafter ‘WCM’ refers to these two genotypes) are globally distributed pests of wheat and maize that have not been recorded in South Africa. Thi...
Alien species are introduced to new regions in many different ways and for different purposes. A number of frameworks have been developed to group such pathways of introduction into discrete categories in order to improve our understanding of biological invasions, provide information for interventions that aim to prevent introductions, enable repor...
The pet trade has been a major pathway for the introduction of vertebrate invaders, but little is known about its role in invertebrate invasions. Here we assess the trade in terrestrial invertebrates (excluding spiders) in South Africa and the potential of this trade to result in biological invasions and impacts. Pet stores, websites, and expositio...
Alien taxa have been introduced to South Africa through a wide variety of pathways, and have subsequently been intentionally or accidentally dispersed across the country. While many introductions to South Africa have been intentional, alien taxa have also been accidentally introduced, or have spread unaided into the country from neighbouring countr...
Biological invasions often transcend political boundaries, but the capacity of countries to prevent invasions varies. How this variation in biosecurity affects the invasion risks posed to the countries involved is unclear. We aimed to improve the understanding of how the biosecurity of a country influences that of its neighbours. We developed six s...
A major challenge for the management of biological invasions is to ensure that data and information from basic inventories and ecological research are used alongside data from the monitoring and evaluation of interventions to trigger and improve policy and management responses. To address this issue, South Africa has committed to report on the stat...
Globalisation has resulted in the movement of organisms outside their natural range, often with negative ecological and economic consequences. As cities are hubs of anthropogenic activities, with both highly transformed and disturbed environments, these areas are often the first point of entry for alien species. We compiled a global database of cit...
The global shipping network facilitates the transportation and introduction of marine and terrestrial organisms to regions where they are not native, and some of these organisms become invasive. South Africa was used as a case study to evaluate the potential for shipping to contribute to the introduction and establishment of marine and terrestrial...
The location of the five selected South African ports, and the benthic bioregions as per Sink et al. [70].
(DOCX)
The number of ocean going vessels arriving at South African ports each year.
(DOCX)
Examples of pairwise-comparisons of the climatic conditions of ports.
(DOCX)
Examples of pairwise-comparisons of the marine environmental conditions of ports.
(DOCX)
Temporal trends in the contribution of different regions to South African merchandise imports.
(DOCX)
The relative contribution of shipping routes from foreign ports to marine and terrestrial establishment debt.
(XLSX)
The seasonal, relative contribution of shipping routes from foreign ports to the marine and terrestrial establishment debt of South African ports.
(DOCX)
Species on the watch list developed for South Africa by Faulkner et al. [71], the environment in which they occur (marine or terrestrial), whether they are found in climate zones or marine ecoregions that are associated with the source ports of high risk shipping routes, and if so whether they have a history of shipping-facilitated introduction.
(D...
The seasonal, relative contribution of shipping routes from foreign ports to the marine and terrestrial establishment debt of South African ports.
(XLSX)
The biogeographical regions as classified by Mead et al. [69] and the position of the five selected South African ports.
(DOCX)
The number of ship visits, number of days travelled, marine environmental distance and terrestrial environmental distance for the South African ports.
(DOCX)
Seasonal variation in the number of ship visits, number of days travelled, marine environmental distance and terrestrial environmental distance of the South African ports.
(DOCX)
The number of marine and terrestrial watch list species that might be transported along the twenty shipping routes to each South African port with the highest relative contribution to marine and terrestrial establishment debt.
(DOCX)
Details of the foreign ports included in the analysis.
(DOCX)
Marine and terrestrial watch list species that might be transported along the twenty shipping routes to each South African port with the highest relative contribution to marine and terrestrial establishment debt.
(DOCX)
Background: Alien organisms are not only introduced from one biogeographical region to another but also spread within regions. As South Africa shares land borders with six countries, multiple opportunities exist for the transfer of alien species between South Africa and other African countries; however, the direction and importance of intra-regiona...
Border control is one of the major approaches used by countries to limit the number of organisms introduced as stowaways. However, it is not feasible to inspect all passengers, cargo and vehicles entering a country, and so efforts need to be prioritised. Here we use South Africa as a case study to assess, based on tourism and trade data and climate...
For the effective prevention of biological invasions, the pathways responsible for introductions must be understood and managed. However introduction pathways, particularly for developing nations, have been understudied. Using the Hulme et al. (J Appl Ecol 45:403–414, 2008) pathway classification, we assessed the South African introduction pathways...
National alien species databases indicate the state of a country's biodiversity and provide useful data for research on invasion biology and the management of invasions. In South Africa there are several different published alien species databases, but these databases were created for different purposes and vary in completeness and information cont...
This study examined high temperature survival and heat shock protein 70 (Hsp70) responses to temperature variation for two marine invertebrate species on sub-Antarctic Marion Island. The isopod Exosphaeroma gigas Leach and the amphipod Hyale hirtipalma Dana had the same tolerance to high temperature. The mean upper temperature which was lethal for...
Understanding the extent to which organisms are affected by climate change and are capable of adapting to warming is essential for managing biodiversity. Recent macrophysiological analyses suggest that range‐related responses to warming may be more coherent (less variable) and predictable in marine than in terrestrial systems.
To examine this gener...
Larval settlement is critical to the establishment and maintenance of marine communities and is influenced by exogenous (bio-physical) and endogenous (behavioural or physiological) factors. Consequently, an understanding of settlement behaviour is specific to the bio-physical conditions and/or ontogenetic stage(s) examined. For intertidal organisms...
