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Urban protected biodiversity areas conserve some of the world's critically endangered and isolated biodiversity while providing essential ecosystem services. However, these urban habitats are threatened by the presence of alien and invasive plants. We studied alien plant species richness and identified the potential predictors in urban protected biodiversity areas in Tshwane Metropolitan Municipality, South Africa. Data on alien plant species were collected through surveys and consultations with protected area managers. We determined the relationship between the observed species richness and potential alien plant species predictors, such as area size, number of visitors, proximity to residential areas, and the year the reserve was proclaimed. We documented 574 records of 189 alien plant species from 60 families across 14 protected areas. Phanerophytes were the most common (46.5%), with many species native to South America, North America, and Africa. Most species have formed naturalised populations (67.7%), followed by invasive populations (20.6%) and casual populations (12%), posing future invasion threats. Most species (55.5%) were introduced as ornamental plants, with many of these species forming invasive populations. Half the recorded species were listed under the NEM:BA A&IS regulations, mostly categorized as 1b. Our findings indicate that the annual number of visitors strongly predicted alien plant species richness in urban protected areas. Additionally, a significant negative correlation was observed between species richness and the proximity to residential areas and years since the proclamation. Understanding the distribution patterns and predictors of species richness is crucial in monitoring invasive alien species and conserving biodiversity in urban environments. [ABSTRACT FROM AUTHOR]

Simple Summary: The global trade of pet birds has grown significantly, leading to more non-native birds being introduced into the wild. Our study examined the potential habitats and environmental factors that might allow pet birds lost and sighted in South Africa to survive outside captivity. Using geographic location data of pet birds, we predicted which areas might be suitable for various species such as the African grey parrot, Budgerigar, Cockatiel, Green-cheeked conure, Monk parakeet, and Rose-ringed parakeet. We found that a significant portion of South Africa could support these species, with some areas being highly suitable. The study highlighted how pet birds could escape or be released into the wild due to human activities, and that urban areas are particularly at risk. This research emphasizes the need for careful monitoring to prevent these birds from becoming invasive, which could impact local ecosystems and biodiversity. The global trade of non-native pet birds has increased in recent decades, and this has accelerated the introduction of invasive birds in the wild. This study employed ensemble species distribution modelling (eSDM) to assess potential habitat suitability and environmental predictor variables influencing the potential distribution of non-native pet bird species reported lost and sighted in South Africa. We used data and information on lost and found pet birds from previous studies to establish and describe scenarios of how pet birds may transition from captivity to the wild. Our study revealed that models fitted and performed well in predicting the suitability for African grey (Psittacus erithacus), Budgerigar (Melopsittacus undulatus), Cockatiel (Nymphicus hollandicus), Green-cheeked conure (Pyrrhura molinae), Monk parakeet (Myiopsitta monachus), and Rose-ringed parakeet (Psittacula krameri), with the mean weighted AUC and TSS values greater than 0.765. The predicted habitat suitability differed among species, with the suitability threshold indicating that between 61% and 87% of areas were predicted as suitable. Species with greater suitability included the African grey, Cockatiel, and Rose-ringed parakeet, which demonstrated significant overlap between their habitat suitability and reported lost cases. Human footprint, bioclimatic variables, and vegetation indices largely influenced predictive habitat suitability. The pathway scenario showed the key mechanisms driving the transition of pet birds from captivity to the wild, including the role of pet owners, animal rescues, adoption practices, and environmental suitability. Our study found that urban landscapes, which are heavily populated, are at high risk of potential invasion by pet birds. Thus, implementing a thorough surveillance survey is crucial for monitoring and evaluating the establishment potential of pet species not yet reported in the wild. [ABSTRACT FROM AUTHOR]

The global increase in the pet trade and ownership of pet birds has heightened the introduction of emerging invasive vertebrate species. We analyzed online databases of lost, found, and sighted non-native pet bird reports in South Africa to evaluate non-native pet bird statuses, investigate geographic patterns, assess species trends, and determine the factors associated with lost pet birds. We identified a total of 1467 case reports representing 77 species across nine families from websites (n = 3) and Facebook pages (n = 13). Most reports of lost birds were within large cities, in populated provinces, including Gauteng, KwaZulu-Natal, and Western Cape. Psittacidae, Psittaculidae, and Cacatuidae were the most dominant families, with African grey (Psittacus erithacus), Cockatiel (Nymphicus hollandicus), and Rose-ringed parakeet (Psittacula krameri) among the top species reported as lost. Lower-priced species were commonly reported as lost, and there was no association between the species' price and the likelihood of being found. In addition, we found a positive relationship between species reported as lost and the number of pet shops, human population size, species size, and docility. There was a sharp increase in lost cases from 2019 onwards; however, males were more frequently lost. Our findings highlight challenges in regulating and monitoring the pet ownership and trade of non-native pet birds and the need to address commonly kept species in conservation efforts. Online resources can be effective tools for passive surveillance of non-native pet bird species, especially potentially invasive ones. [ABSTRACT FROM AUTHOR]

Parthenium hysterophorus L. (Asteraceae), commonly known as famine weed in South Africa, is one of the most invasive weeds worldwide, accountable for losses to biodiversity, agriculture, the economy, and the health of livestock and human beings. The spread of this weed is not easy to manage or reverse. With globalization, trade, and human movement, it will continue to spread, allowing its range to expand into new areas. This weed has serious adverse effects on rangeland and agricultural crop production. Because of its unique characteristics, its invasiveness and competitive success rates are attributed to its high reproductive ability, fast growth rate, tolerance to environmental stresses, climate change adaptability, allelopathic potential, and unpalatability to animals. Parthenium hysterophorus dominates diverse habitats by spreading quickly as a contaminant of grain and other crop products and through farm machinery. It is widely distributed and has become problematic in various countries, including South Africa. It has successfully invaded several provinces in the country since its introduction in 1880. Since plant invasions are not universal, this study aimed to review research that has been conducted on the aggressive weed P. hysterophorus to understand the ecological characteristics that enable its successful establishment, the economic costs associated with its detrimental impacts, and to briefly assess knowledge gaps to improve its management strategies. [ABSTRACT FROM AUTHOR]

Preserving the dwindling native biodiversity in urban settings poses escalating challenges due to the confinement of remaining natural areas to isolated and diminutive patches. Remarkably scarce research has scrutinised the involvement of institutions, particularly universities, in introducing alien plant species in South Africa, thus creating a significant gap in effective monitoring and management. In this study, the Tshwane University of Technology in Tshwane Metropole, South Africa serves as a focal point, where we conducted a comprehensive survey of alien plants both within the university premises and beyond its confines. The investigation involved the classification of invasion status and a meticulous assessment of donor and recipient dynamics. Our findings encompass 876 occurrence records, revealing the presence of 94 alien plant species spanning 44 distinct families. Noteworthy occurrences among the dominant plant families are Asteraceae and Solanaceae. Herbaceous and woody plants emerged as the most prevalent alien species, with common representation across both sampling sites. A substantial majority of recorded species were initially introduced for horticultural purposes (51%) before escaping and establishing self-sustaining populations (62%). Furthermore, 43 species identified are listed in South African invasive species legislation, with some manifesting invasive tendencies and altering the distribution of native species in the remaining natural areas. The notable overlap in species observed between the university premises and adjacent areas provides crucial insights into the influence of institutions on the dynamics of plant invasions within the urban landscape. This underscores the prevailing gaps in the management of invasive alien plants in urban zones and accentuates the imperative of an integrated approach involving collaboration between municipalities and diverse institutions for effective invasive species management in urban environments. [ABSTRACT FROM AUTHOR]

Invasive alien species represent one of the main threats to biodiversity and species extinction. This is the case for the genus Prosopis, among which Prosopis velutina is the most invasive and common tree species along the Molopo River in the North-West Province, impacting native plant communities. However, its impact on the composition and diversity of native woody species remains poorly investigated in the area. Thus, this study aimed to assess the impact of P. velutina on native woody plant composition and diversity across three sites along the Molopo River. At each site, five quadrats of 20 × 20 m2 were randomly established in invaded and adjacent uninvaded stands. A comparative methodological approach was adopted, and the woody plants in invaded and uninvaded stands with similar site conditions were sampled. The results showed that native woody species density differed significantly (p < 0.05) between invaded and uninvaded stands, except for Bray sites, where there was a marginal difference (p = 0.6). The overall native woody species density decreased by 79.7% in the invaded stand. However, non-metric multidimensional scaling (nMDS) and analysis of similarity (ANOSIM) indicated significant differences in native tree composition between invaded and uninvaded stands at all sites. In all three sites, all ecological indices had significantly lower values in invaded stands compared to uninvaded stands. The decrease in all ecological indices in invaded over uninvaded stands indicated that P. velutina invasion reduced the diversity of native woody plant species. Due to the incessant spread of P. velutina, it may become a long-term dominant species with an increasing impact on the native vegetation. Therefore, the findings of this study call for urgent management and appropriate control measures against the ongoing spread of this invader within the riparian zones of the Molopo River in North-West Province. [ABSTRACT FROM AUTHOR]

The present study reports on the occurrence of Ipomoea hederifolia L. in South Africa. The established populations of Ipomoea hederifolia were detected in 2019 and 2020 in different locations in the Limpopo Province, with herbarium records showing at least four other localities in the country. Further work is now needed to determine the impact of Ipomoea hederifolia on native biota and agricultural production. [ABSTRACT FROM AUTHOR]

Leucanthemum vulgare, Lam. (Asteraceae) (ox-eye daisy) is a perennial herb and an aggressive invader native to Eurasia. Today, the species is found in all continents except for Antarctica, and is an invasive in many countries. In this study, we present records of invading populations of Leucanthemum vulgare in the Limpopo province, South Africa, covering over 21.717 m2 of critically endangered grassland. Management guidelines for Leucanthemum vulgare are provided. [ABSTRACT FROM AUTHOR]

It is generally accepted that urbanisation is changing the composition of species, mostly in urban and surrounding areas, through intentional introduction. The South African National Status Report of 2017 on biological invasions has shown that there is a dearth of knowledge about the invasion status of many invasive alien species in many parts of the country, such as the critically threatened vegetation, Woodbush Granite Grassland (WGG) in Limpopo Province. Consequently, the present study investigated the status of alien plants species in WGG. A roadside survey was carried out in Haenertsburg Village and its vicinity. Roads were used as survey units, and the dumpsite was used as a high risk area. A total of 136 species were identified, belonging to 46 botanical families. This study report the occurrence of 72 species which are regulated by the South Africa's National Environmental Management: Biodiversity Act (NEMBA, Act 10 of 2004). The present study found results significantly different from existing databases (X2 = 16.33473, p = .0001). Included in our list are alien species that need urgent eradication: Coreopsis lanceolata L., Cytisus scoparius (L.) Link, Iris pseudacorus L., Pueraria montana (Lour.) Merr, - and Rubus species as NEMBA category 1a species. Illegal dumping of agricultural waste was found to be one of the contributing factors to IAS in the area. Our study shows that Woodbush Granite Grassland is facing a new threat from invasive species. [ABSTRACT FROM AUTHOR]

Verbesina encelioides (Cav.) Benth. & Hook. Fil ex Gray (Asteraceae) is a perennial herb species belonging to the family Asteraceae. The plant is an aggressive obligate outbreeder weed that has invaded vast expanses of pastures, orchards, and forest areas in tropical and subtropical regions. The purpose of this study was to determine the suitability of current and potential future habitats for V. encelioides, an invasive weed in South Africa, using species distribution modelling techniques with the sdm package in R. The result of the ensemble model, based on current climatic conditions, highlights that Verbesina encelioides has a high probability of occurrence in all nine provinces of South Africa, across all the projected future scenarios, namely, 2030, 2050, 2070 and 2090. Area values ranged from 810,612.09 km2 in 2070, an increase of 4.23% over the current projection, to 663,356.44 km2 in 2090, a decrease of 14.7% from the current projection. The outcome of these predictions showed that V. encelioides would benefit from the predicted climate change in South Africa. The findings could be used as a warning to implement early detection and a rapid response, or for developing one. [ABSTRACT FROM AUTHOR]

The present study reports on the occurrence of Ipomoea hederifolia L. in South Africa. The established populations of Ipomoea hederifolia were detected in 2019 and 2020 in different locations in the Limpopo Province, with herbarium records showing at least four other localities in the country. Further work is now needed to determine the impact of Ipomoea hederifolia on native biota and agricultural production. [ABSTRACT FROM AUTHOR]

It is generally accepted that urbanisation is changing the composition of species, mostly in urban and surrounding areas, through intentional introduction. The South African National Status Report of 2017 on biological invasions has shown that there is a dearth of knowledge about the invasion status of many invasive alien species in many parts of the country, such as the critically threatened vegetation, Woodbush Granite Grassland (WGG) in Limpopo Province. Consequently, the present study investigated the status of alien plants species in WGG. A roadside survey was carried out in Haenertsburg Village and its vicinity. Roads were used as survey units, and the dumpsite was used as a high risk area. A total of 136 species were identified, belonging to 46 botanical families. This study report the occurrence of 72 species which are regulated by the South Africa's National Environmental Management: Biodiversity Act (NEMBA, Act 10 of 2004). The present study found results significantly different from existing databases (χ² = 16.33473, p = .0001). Included in our list are alien species that need urgent eradication: Coreopsis lanceolata L., Cytisus scoparius (L.) Link, Iris pseudacorus L., Pueraria montana (Lour.) Merr, - and Rubus species as NEMBA category 1a species. Illegal dumping of agricultural waste was found to be one of the contributing factors to IAS in the area. Our study shows that Woodbush Granite Grassland is facing a new threat from invasive species. [ABSTRACT FROM AUTHOR]

Leucanthemum vulgare, Lam. (Asteraceae) (ox-eye daisy) is a perennial herb and an aggressive invader native to Eurasia. Today, the species is found in all continents except for Antarctica, and is an invasive in many countries. In this study, we present records of invading populations of Leucanthemum vulgare in the Limpopo province, South Africa, covering over 21.717 m² of critically endangered grassland. Management guidelines for Leucanthemum vulgare are provided. [ABSTRACT FROM AUTHOR]

Invasive species typically establish in areas outside their natural distribution through accidental introduction and accidental release or escape. Some species are introduced legally for economic and social benefits such as recreational hunting, the pet trade and research through established permitting processes driven by appropriate laws and regulations. The aim of this study was to determine whether there is a trend in demand for regulated alien taxa based on permit requests and to ascertain the activities for which permits requested in order to infer the drivers of alien taxa demand in South Africa. We examined the Department of Environmental Affairs (DEA) species permitting application database records from October 2015 to February 2018. From the total of 1,390 permit applications during this period, 79.2% of the permits were issued for various economic and social activities associated with the following species: Red lechwe (Kobus leche leche, Gray), fallow deer (Dama dama Linnaeus), Grass carp (Ctenopharyngodon idella Valenciennes), Nile tilapia (Oreochromis niloticus Linnaeus) and rose‐ring parakeet (Psittacula krameri Scopoli). Our results suggest that economic activities such as hunting and sport fishing are driving the demand for some regulated species. We suggest reinforced monitoring and inspection for permit compliance for species sought to minimise potential escape. [ABSTRACT FROM AUTHOR]

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Background Lists are fundamental for guiding policy and management of biological invasions. The process of developing regulatory lists of alien and invasive taxa should be based on scientific evidence through an objective, transparent and consistent process. Objectives In this study, we review the development of the lists for the alien and invasive species regulations in terms of section 97(1) of the National Environmental Management: Biodiversity Act , 2004 (NEM:BA) (Act No. 10 of 2004). Method Lists published in the National Government Gazette were compared and assessed for changes in the taxa listed and their status between 2009 and 2016. Minutes from expert workshops convened to inform the listing were reviewed. Relevant information such as the criteria for listing taxa was extracted from minutes of the workshops. Results Three draft versions were produced and published in the Government Gazette for public comment before the final list was published in August 2014 and promulgated in October 2014. The list is to be reviewed regularly and additional species can be added, and the status of species can be changed as additional evidence of threat levels is available – and was even amended in May 2015. The various stakeholders involved in the listing process were academics, conservation experts, managers and the general public through an inclusive process which included participation workshops or through public comment. A scoring tool based on the likelihood of invasion versus the impact of invasion was recommended for evaluating the risk of a species, but was rarely used. A number of issues relating to conflicts and approaches for listing were faced during development of lists. Conclusion We conclude with some recommendations for future refinements in the listing process, including improving transparency and participation as well as developing standardised approaches for listing. [ABSTRACT FROM AUTHOR]

An inventory of wetland vegetation across the country generated a list of the most common invasive alien plants across South Africa. Many of the plants on that list do not correspond with the priorities in the programmes for alien control across the country, as they are not listed on a government produced list that guides the priorities for alien control. We explore the reasons for this situation. We argue that because wetlands are such important parts of the landscape, invasive aliens in wetlands are of special concern, and there should be more alignment between alien control programmes and wetland rehabilitation programmes. This alignment starts by considering the full number of species that form a threat to wetland habitats, but also considers which pesticides to use, erosion and recolonisation in wetlands, planting indigenous vegetation after aliens have been removed, and strategising by working from upstream to downstream. Existing alien control programmes for specific grasses (some relatively new to the country and in the phase of early detection) and floating aquatic plants may guide how to tackle the invasions of grasses and forbs that have been established in South African wetlands for an extended period of time. [ABSTRACT FROM AUTHOR]

The article presents commentary on diverse group of African emerging researchers, on why are black South African students less likely to consider studying biological sciences. It mentions that strong racial undertones as well as poor and unethical research practices that has been intensely divisive, managing to engender stereotypes, anger, and disappointment. It also informs that the research contained therein, has violated many of these governing principles.

The threat posed by invasive non-native species worldwide requires a global approach to identify which introduced species are likely to pose an elevated risk of impact to native species and ecosystems. To inform policy, stakeholders and management decisions on global threats to aquatic ecosystems, 195 assessors representing 120 risk assessment areas across all six inhabited continents screened 819 non-native species from 15 groups of aquatic organisms (freshwater, brackish, marine plants and animals) using the Aquatic Species Invasiveness Screening Kit. This multi-lingual decision-support tool for the risk screening of aquatic organisms provides assessors with risk scores for a species under current and future climate change conditions that, following a statistically based calibration, permits the accurate classification of species into high-, medium- and low-risk categories under current and predicted climate conditions. The 1730 screenings undertaken encompassed wide geographical areas (regions, political entities, parts thereof, water bodies, river basins, lake drainage basins, and marine regions), which permitted thresholds to be identified for almost all aquatic organismal groups screened as well as for tropical, temperate and continental climate classes, and for tropical and temperate marine ecoregions. In total, 33 species were identified as posing a 'very high risk' of being or becoming invasive, and the scores of several of these species under current climate increased under future climate conditions, primarily due to their wide thermal tolerances. The risk thresholds determined for taxonomic groups and climate zones provide a basis against which area-specific or climate-based calibrated thresholds may be interpreted. In turn, the risk rankings help decision-makers identify which species require an immediate 'rapid' management action (e.g. eradication, control) to avoid or mitigate adverse impacts, which require a full risk assessment, and which are to be restricted or banned with regard to importation and/or sale as ornamental or aquarium/fishery enhancement., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)