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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 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]