Border control for stowaway alien species should be prioritised based on variations in establishment debt

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 matching techniques, the number of stowaway species that might be introduced (‘colonisation pressure’) and the likelihood that once introduced, these organisms will establish (‘likelihood of establishment’). These results were used to explore how the number of species that are likely to establish (‘establishment debt’) varies across donor regions and seasons. A simple theoretical model was then used to compare four strategies for prioritising border control inspections: no prioritisation; based on colonisation pressure; based on likelihood of establishment; and based on both colonisation pressure and likelihood of establishment. Establishment debt was greatest in southern hemisphere spring and autumn when South Africa is climatically similar to northern hemisphere countries with which there are strong, consistent trade and tourism links (i.e. colonisation pressure varied little seasonally, but likelihood of establishment did vary across the seasons). Prioritising inspections based on both colonisation pressure and the likelihood of establishment was clearly the most effective strategy, with this strategy detecting at least 6% more potential invaders than the other strategies. While there are many practical limitations to the implementation of such prioritised inspection strategies, the results highlight the importance of national and regional studies of establishment debt.This work was supported by the South African National Department of Environment Affairs through its funding of the South African National Biodiversity Institute’s Invasive Species Programme. Additional funding was provided by the DST-NRF Centre for Invasion Biology. MR acknowledges funding from the South African Research Chairs Initiative of the Department of Science and Technology and National Research Foundation of South Africa.http://www.elsevier.com/locate/jenvman2017-09-30hb2016Zoology and Entomolog

Native-alien populations—an apparent oxymoron that requires specific conservation attention

DATA AVAILABILITY : Data for this study are available on request from the authors.SUPPLEMENTARY MATERIAL 1. FILE S1. Authors: Takalani Nelufule, Mark P. Robertson, John R. U. Wilson, Katelyn T. Faulkner Data type: Methods (docx. file) Explanation note: Methods for the simulation that illustrates that native-alien populations are likely to be closer geographically to their native range than populations introduced from other countries. Copyright notice: This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited. Link: https://doi.org/10.3897/neobiota.74.81671.suppl1SUPPLEMENTARY MATERIAL 2. FILE S2. Authors: Takalani Nelufule, Mark P. Robertson, John R. U. Wilson, Katelyn T. Faulkner Data type: Methods (docx. file) Explanation note: Method for determining whether native-alien populations tend to have a greater number of closely related taxa (congeneric and confamilial species) in their introduced range than alien populations introduced from other countries.. Copyright notice: This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited. Link: https://doi.org/10.3897/neobiota.74.81671.suppl2UPPLEMENTARY MATERIAL 3. FILE S3. Authors: Takalani Nelufule, Mark P. Robertson, John R. U. Wilson, Katelyn T. Faulkner Data type: Methods (docx. file) Explanation note: Method for testing whether native-alien populations are particularly prevalent in large, ecologically diverse countries. Copyright notice: This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited. Link: https://doi.org/10.3897/neobiota.74.81671.suppl3Many 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 that result from the human-mediated dispersal of individuals of a species beyond a biogeographical barrier to a point beyond that species’ native range, but that is still within the same political entity as parts of the species’ native range. Based on these criteria, we consider native-alien populations to be biological invasions. However, we argue that, in comparison to other alien populations, native-alien populations: 1) are likely to be closer geographically to their native range; 2) are likely to be phylogenetically and ecologically more similar to native species in their introduced range; and 3) options to control their introduction or manage them will likely be more limited. We argue this means nativealien populations tend to differ from other alien populations in the likelihood of invasion, the types of impacts they have, and in how they can be most effectively managed. We also argue that native-alien populations are similarly a distinct phenomenon from native populations that are increasing in abundance or range extent. And note that native-alien populations are expected to be particularly common in large, ecologically diverse countries with disjunct biomes and ecoregions. Reporting, monitoring, regulating and managing native-alien populations will, we believe, become an increasingly important component of managing global change.The South African Department of Forestry, Fisheries and the Environment (DFFE), TISO Foundation and the University of Pretoria.https://neobiota.pensoft.net/https://neobiota.pensoft.netam2023Zoology and Entomolog

The wheat curl mite (Aceria tosichella, Prostigmata: Eriophyidae) could establish in South Africa

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. This study examined whether WCM could be introduced to, and establish in, South Africa. Trade data were used to determine whether viable pathways of introduction are present. A species distribution model and data on wheat and maize production were used to determine whether WCM could establish where its hosts are grown. WCM is most likely to be introduced to South Africa as a contaminant of maize from Argentina, Brazil, Uruguay, and USA; on live plant imports from China and Germany; and on seed imports from Brazil and Australia. Some of these pathways are not currently prominent, but could increase in the future. Parts of South Africa were predicted by the species distribution model to be climatically suitable for WCM, and within some of these areas the host crops are grown. Therefore, if WCM is introduced, it is likely to establish and cause extensive damage to agriculture. We recommend that WCM be considered for inclusion in South Africa’s import conditions as a quarantine pest.The South African Department of Environment, Forestry and Fisheries (DEFF)https://www.tandfonline.com/loi/tafz202022-03-09hj2022Zoology and Entomolog

Classifying the introduction pathways of alien species: are we moving in the right direction?

This paper emerged from the workshop on ‘Frameworks used in Invasion Science’ hosted by the DSI-NRF Centre of Excellence for Invasion Biology in Stellenbosch, South Africa, 11–13 November 2019.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 reporting to national and international organisations and facilitate the prediction of threats. The introduction pathway classification framework proposed by the Convention on Biological Diversity (CBD) as a global standard is comprised of six main categories and 44 sub-categories. However, issues have arisen with its implementation. In this position paper, we outline five desirable properties of an introduction pathway classification framework – it should be compatible (i.e. the level of detail of the categories is similar to that of the available data), actionable (i.e. categories link to specific interventions), general (i.e. categories are applicable across the contexts that are of interest (e.g. taxa, habitats and regions)), equivalent (i.e. categories are equivalent in their level of detail) and distinct (i.e. categories are discrete and easily distinguished) – termed the CAGED properties. The six main categories of the CBD framework have all of the CAGED properties, but the detailed sub-categories have few. Therefore, while the framework has been proposed by the CBD as a global standard and efforts have been made to put it into practice, we argue that there is room for improvement. We conclude by presenting scenarios for how the issues identified could be addressed, noting that a hybrid model might be most appropriate.The South African Department of Forestry, Fisheries and the Environment (DFFtE)http://www.pensoft.net/journals/neobiotaam2021Zoology and Entomolog

The balance of trade in alien species between South Africa and the rest of Africa

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-regional spread is unclear. OBJECTIVES : The aim of this study was to gain a greater understanding of the introduction of alien species into Africa and the spread of species between South Africa and other African countries. METHOD : We developed scenarios that describe the routes by which alien species are introduced to and spread within Africa and present case studies for each. Using data from literature sources and databases, the relative importance of each scenario for alien birds and insect pests of eucalypts was determined, and the direction and importance of intra-regional spread was assessed. RESULTS : Alien species from many taxonomic groups have, through various routes, been introduced to and spread within Africa. For birds and eucalypt insect pests, the number of species spreading in the region has recently increased, with South Africa being a major recipient of birds (14 species received and 5 donated) and a major donor of eucalypt insect pests (1 species received and 10 donated). For both groups, many introduced species have not yet spread in the region. CONCLUSION : The intra-regional spread of alien species in Africa represents an important and possibly increasing threat to biosecurity. To address this threat, we propose a framework that details how African countries could cooperate and develop a coordinated response to alien species introductions.This paper was initially delivered at the 43rd Annual Research Symposium on the Management of Biological Invasions in South Africa, Goudini Spa, Western Cape, South Africa on 18-20 May 2016.The South African National Department of Environment Affairs through its funding of the South African National Biodiversity Institute’s Invasive Species Programme, the DST-NRF Centre for Invasion Biology, the South African Research Chairs Initiative of the Department of Science and Technology and National Research Foundation of South Africa.http://abcjournal.org/index.php/ABCam2018Forestry and Agricultural Biotechnology Institute (FABI)Zoology and Entomolog

The threats posed by the pet trade in alien terrestrial invertebrates in South Africa

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 expositions were visited, and a list of the taxa traded was compiled. DNA barcoding was used to determine if the species were correctly identified in the trade. Information on invasion history and impact elsewhere was used to assess the potential for species to become invasive and have impact in South Africa. We found 53 alien terrestrial invertebrate taxa that were traded, although only 36 of these matched a valid species name. Of 11 species tested using DNA barcoding nine were correctly identified. Species accumulation curves were produced, but did not reach an asymptote, suggesting there are many species in the trade that were not recorded. The most common species were used as food for pets, rather than as pets themselves. None of the species were reported to be invasive elsewhere, and few had records of causing negative impacts (the exception being moderate impacts to human health caused by venomous scorpions). Therefore, there is little evidence that the invertebrates traded pose a significant threat to South Africa. However, given uncertainties in which taxa are traded and the lack of data on invasiveness and impact, there might be a significant invasion debt. We recommend continued monitoring and engagement with the industry.The South African Department of Forestry, Fisheries, and the Environment (DFFtE)http://www.elsevier.de/jnc2021-06-01hj2020Zoology and Entomolog

Prioritising surveillance for alien organisms transported as stowaways on ships travelling to South Africa

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 alien species (i.e. establishment debt) and to assess how this varies across shipping routes and seasons. As a proxy for the number of species introduced (i.e. 'colonisation pressure') shipping movement data were used to determine, for each season, the number of ships that visited South African ports from foreign ports and the number of days travelled between ports. Seasonal marine and terrestrial environmental similarity between South African and foreign ports was then used to estimate the likelihood that introduced species would establish. These data were used to determine the seasonal relative contribution of shipping routes to South Africa's marine and terrestrial establishment debt. Additionally, distribution data were used to identify marine and terrestrial species that are known to be invasive elsewhere and which might be introduced to each South African port through shipping routes that have a high relative contribution to establishment debt. Shipping routes from Asian ports, especially Singapore, have a particularly high relative contribution to South Africa's establishment debt, while among South African ports, Durban has the highest risk of being invaded. There was seasonal variation in the shipping routes that have a high relative contribution to the establishment debt of the South African ports. The presented method provides a simple way to prioritise surveillance effort and our results indicate that, for South Africa, port-specific prevention strategies should be developed, a large portion of the available resources should be allocated to Durban, and seasonal variations and their consequences for prevention strategies should be explored further. (Résumé d'auteur

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Understanding and managing the introduction pathways of alien taxa : South Africa as a case study

CITATION: Faulkner, K.T. et al. 2016. Understanding and managing the introduction pathways of alien taxa: South Africa as a case study. Biological Invasions, 18(1):73-87. doi:10.1007/s10530-015-0990-4The original publication is available at https://www.springer.com/journal/10530For 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 in terms of the number of introductions, the invasion success of introduced taxa, how the pathways have changed over time, and how these factors vary for vertebrates, invertebrates and plants. Pathway and date of introduction, region of origin, distribution and invasion status data for 2111 alien taxa were extracted from databases. Most alien and invasive taxa were deliberately introduced and subsequently escaped captivity or cultivation. Pathway prominence also varied temporally and across organism types. Vertebrates and plants were largely escapes and although most plant escapes have become invasive, this is not the case for vertebrates. However the number of new plant and vertebrate escapes has increased over time. Invertebrates have been deliberately released or unintentionally introduced as contaminants or stowaways. For invertebrates the number of release, contaminant and stowaway introductions has increased, and most contaminants and stowaways have become invasive. As effective screening procedures are in place for invertebrates released for biological control, the major threats for South Africa are from vertebrate and plant escapes and invertebrate contaminants and stowaways. We recommend improvements to risk assessment and education to prevent escapes, and prioritised inspection strategies to reduce stowaway and contaminant introductions. Finally, as introduction pathways and introduced taxa change temporally, biosecurity decisions need to be informed by information on current and future pathways.Publisher’s versio

Stronger regional biosecurity is essential to prevent hundreds of harmful biological invasions

CITATION: Faulkner, K.T., Robertson, M.P. & Wilson, J.R.U. 2020. Stronger regional biosecurity is essential to prevent hundreds of harmful biological invasions. Global Change Biology, 26(4):2449-2462. doi:10.1111/gcb.15006The original publication is available at https://onlinelibrary.wiley.com/journal/13652486Biological 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 scenarios that describe biological invasions in regions with contiguous countries. Using data from alien species databases, socio-economic and biodiversity data and species distribution models, we determined where 86 of 100 of the world's worst invasive species are likely to invade and have a negative impact in the future. Information on the capacity of countries to prevent invasions was used to determine whether such invasions could be avoided. For the selected species, we predicted 2,523 discrete invasions, most of which would have significant negative impacts and are unlikely to be prevented. Of these invasions, approximately a third were predicted to spread from the country in which the species first establishes to neighbouring countries where they would cause significant negative impacts. Most of these invasions are unlikely to be prevented as the country of first establishment has a low capacity to prevent invasions or has little incentive to do so as there will be no impact in that country. Regional biosecurity is therefore essential to prevent future harmful biological invasions. In consequence, we propose that the need for increased regional co-operation to combat biological invasions be incorporated in global biodiversity targets.Publisher’s versio