OpenUCT :: Browsing by Author "Janion-Scheepers, Charlene"

Browsing by Author "Janion-Scheepers, Charlene"

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Open Access
Barcoding alien invertebrates and biological control agents in South Africa, with a focus on the natural enemies of Thaumatotibia leucotreta (Meyrick)
(2025) Pitcher, Tristan; Janion-Scheepers, Charlene; Van Noort, Simon
Alien invertebrate species and agricultural pests pose economic challenges through impeding crop production and threatening biodiversity in South Africa. Invertebrates are particularly successful invaders owing to their short generation times, high reproductive output, widespread occurrence across terrestrial, freshwater and marine environments, and considerable morphological diversity. The false codling moth, Thaumatotibia leucotreta (Meyrick), is a notable pest in South Africa, as it attacks important export crops such as citrus and stone fruit, greatly reducing returns on these exports, while threatening the country's access to international markets. While several wasp species have been recorded parasitising T. leucotreta, their distribution in South Africa is poorly documented, while only two species have been trialled as biological control agents against the pest. The projected shifts in species distribution patterns due to globalisation and climate change underscore the need for comprehensive baseline genetic and distribution data of alien invertebrate species and biological control agents. Such data are important for mitigating and managing biological invasions. A useful genetic tool in this respect, is DNA barcoding, which uses a short genetic marker to aid in the delimitation of species. However, there is no recent database of barcoded alien invertebrates and biological control agents in South Africa. In addition, thermal physiological traits of invertebrates are useful data for modelling species distributions, especially under climate change. However, current baseline physiological data of important pests and their biological control agents remain limited, negatively impacting our understanding of their present and future distribution patterns. This study aimed to: 1) review the DNA barcoding status of alien invertebrates and biological control agents in South Africa; 2) sample T. leucotreta parasitoid wasps in organic and IPM orchards within the Western Cape; and 3) to determine the critical thermal limits of Trichogrammatoidea cryptophlebiae Nagaraja, an egg parasitoid used as a biological control agent against T. leucotreta, in the laboratory. The review of alien invertebrate species in South Africa identified major gaps in DNA barcoding, particularly among arachnids and platyhelminths (flatworms). While 66.8% of all alien invertebrate species in the South African dataset were accessioned on BOLD (Barcoding of Life Datasystems), only 24.3% of these records represented specimens collected in South Africa. Furthermore, 44.6% of alien invertebrate species records on BOLD were not accompanied by images. This research has identified important gaps in the baseline knowledge of alien invertebrate species, pests, and biological control agents in South Africa. The paucity of South African specimens and image records on BOLD constrains the effectiveness of these records for identification. Despite conducting sampling under ideal conditions, no T. leucotreta parasitoids were sampled in the Western Cape. This absence may be attributed to low parasitoid population densities or suboptimal sampling methodology. The lack of T. leucotreta parasitoids sampled in the Western Cape suggests that natural wasp populations may be insufficient for pest control, supporting the case for augmentative biological control whilst highlighting the need for more intensive sampling and trials of parasitoid wasps as biological control agents. Using thermal tolerance assays, the critical thermal minimum and maximum of T. cryptophlebiae were determined to be 8.15°C ± 0.58°C and 44.50°C ± 0.41°C (mean ± SE), respectively. The critical thermal minimum of T. cryptophlebiae determined in this study exceeds the wasp's lower developmental threshold, indicating that adult wasps are less cold-tolerant than other life stages. These thermal tolerance data provide valuable baseline information for predicting potential distribution shifts of T. cryptophlebiae under climate change scenarios. Overall, this study contributed to baseline data on alien invertebrate, pest and biological control agent species, including T. leucotreta and its parasitoids, in South Africa. These baseline data underscore the need for further research on the distribution and biology of these important species.
Open Access
Belowground impacts of regenerative agriculture in a South African seed production system
(2023) Nel, Gemma; Janion-Scheepers, Charlene
Intensive agriculture, that is environmentally detrimental, is a serious global problem. Widespread deforestation as a means to expand agricultural areas, and the overuse of agrochemicals causes rapid biodiversity loss, large scale soil erosion and agroecosystems to become stuck in negative feedback cycles. Agricultural management thus plays an important role in the stability and resilience of agroecosystems. Shifts towards more sustainable practices have been encouraged, with regenerative agriculture gaining a lot of traction over the years. It is crucial to understand the impact of various management strategies on various aspects of agroecosystems to gain a greater, more holistic understanding. A newly established long-term trial provided an ideal opportunity to explore and compare the impacts of regenerative agriculture with conventional agriculture within a cauliflower seed production system in the Western Cape of South Africa. Specifically, this study investigated the effects of different management strategies on soil fauna and the important soil processes they govern. The treatments included “conventional agriculture” (C) which was the use of agrochemicals and tillage, “mulching combined with compost” (MC), “cover cropping” (CC), and crop rotation. To determine the changes in soil fauna community assemblages and species richness, two components of the belowground fauna were investigated. Firstly, arthropod diversity indices were compared between conventional agriculture and regenerative agriculture management strategies (Chapter 2). Four arthropod taxa were selected for study, providing information on the macrofauna and mesofauna of the area. These included ants, beetles, spiders, and springtails. Soil fauna were sampled every two months for a year, using pitfall traps. Differences in species richness and abundance of the four study taxa were assessed in relation to agricultural treatment, sites, crop lines, and sampling times. ANOSIM (Analysis of Similarities) was conducted to determine sample differences between the study factors of site, treatment, crop rotation and sampling time. The presence of particular species was assessed for associations between factors, to determine whether any species show influential characteristics towards particular agricultural treatments, sites or seasons. It was found that total arthropod abundance and species richness was generally greatest during the pre-trial sampling event that took place in February 2021. Arthropod abundance and species richness responses were taxa specific and differed between field sites and sampling times. Arthropod communities within each site, treatment, crop line and season, were not more similar to the communities of different sites, treatments, crop lines and seasons. Several species of interest were determined based on their presence within the study factors. Particularly, the spider Pardosa crassipalpis, displayed agrobiont behaviour within this agroecosystem and will be a key species of interest for further monitoring within the trial. The presence of this highly abundant species was particularly noted at the site Jondu, within mulching and compost treatments, and typically during the final (February 2022) sampling period. Furthermore, the abundance of species of springtails recorded within this agroecosystem is remarkable. Native Entomobryidae made up more than 50% of all abundances and more than half of all species recorded. These species fall within a group of collembolans that display remarkably high thermal tolerances and desiccation resistance, within such an arid agroecosystem. Secondly, decomposition rate (k), remaining litter mass (g), carbon to nutrient ratios and soil mesofauna community compositions were compared between agricultural treatments, by means of a litter bag experiment (Chapter 3). Multivariate analyses based on decomposition rate with respect to temporal changes showed significant site, treatment and temporal effects on decomposition rate. On average, decomposition rates were highest for litter bags placed at the site Jondu. Conventional agricultural treatment showed significantly lower decomposition rates and mass loss than the other two treatments. Site and sampling times were the most important factors explaining the variation in carbon to nutrient ratios. Carbon to nutrient ratios showed overall decreases over time, with particular site-specific responses observed. Particularly interestingly, C/N ratios showed considerable site-specific responses, with litterbags at Jondu recording decreased C/N over time, compared to increased C/N at the other sites. This study provided essential baseline information for the system. Treatment effects were not as evident as expected. However, due to the study being conducted within the first established year of the trial, this may be expected. Site effects were far more prominent than treatment or crop rotation effects. Differences in soil conditions between sites may be accounting for a great deal of the variation in arthropod community assemblages and litter decomposition. Continued assessment of the impact of agricultural management strategies and crop rotation as the trial progresses and becomes more established will prove useful in determining effects of regenerative agriculture on soil fauna and litter decomposition.
Open Access
Belowground success: Collembola as indicators of restoration progress following active and passive restoration
(2024) Visagie, Marizanne; Janion-Scheepers, Charlene; Esler, Karen
Due to the unprecedented changes and fragmentation of ecosystems caused by human land uses and exploitation, ecological restoration is an increasingly essential topic in the field of conservation. In South Africa, a predominantly semi-arid country, invasive tree species negatively impact the limited water resources by reducing runoff and disrupting water related ecosystem services. Private organizations, as well as the Western Cape government, have been clearing riparian areas of alien invasive trees along rivers in the Western Cape since 1995. Areas investigated in this study included three riparian sites along the Berg River in the Western Cape, habitats that are also vulnerable to environmental changes. The study focussed on monitoring restoration efforts by the Berg and Breede River Rehabilitation Programme, which involved clearing of alien invasive trees along the Berg River, followed by either active restoration (follow-up clearing and monitoring) or passive restoration (no treatment after alien plant removal). Despite soils being so vital in the field of restoration, most studies to date have investigated the aboveground impacts of restoration, with few studies on invertebrate taxa, especially belowground soil fauna. This study assessed Collembola (springtail) communities between active and passive restoration sites in comparison to invaded, non-restored sites as reference sites. Sampling was conducted during winter (2020) and winter and spring (2021) to consider the seasonal effects. From a total of 250 samples, 77,880 individual specimens and 34 morphospecies were collected and identified. Results showed that Collembola assemblages differed significantly among the different restoration treatments, especially between actively restored and invaded sites. Results from the study further suggested that active restoration may be the most effective method for bringing these communities closer to their natural state, since active restoration was found to be the most significantly different from invaded sites in terms of Collembola community composition (Kruskal-Wallis, p< 0.005) during spring 2020 and spring 2021 (p
Open Access
Distribution and phylogenetic inference within the flightless spring katydids (Tettigoniidae: Brinckiella Chopard, 1955) in the Greater Cape Floristic Region
(2022) Guta, Ricardo José; Janion-Scheepers, Charlene; Naskrecki, Piotr
The genus Brinckiella is an endemic group from the Greater Cape Floristic region (GCFR) with several undescribed species. Some of them are of conservation concern, categorized by IUCN as Endangered (EN) and Vulnerable (VU) due to their restricted distribution caused by livestock overgrazing, agriculture, and urbanization. However, data are still missing to fully assess their distribution pattern and conservation status. Moreover, although the phylogeny of katydids was recently inferred, Brinckiella was not included in that analysis. Thus, its closest relatives and evolutionary history are still unknown. This study aimed to investigate the distribution and phylogenetic inference within the genus Brinckiella, map the distribution of its species, delimit the species through taxonomy and genetics, and elucidate the phylogenetic relationship and divergence time within the genus. Specimens were collected by hand and sweep netting. Phylogenetic inference was done using the COI gene and analysed under Maximum likelihood and Bayesian inference. This study identified 13 morphospecies of Brinckiella, of which five are new, undescribed species. The genus is currently distributed in 27 vegetation types in three biomes, and apart from the Fynbos and Succulent Karoo biomes, the genus also occurs in the Azonal vegetation biome. Fynbos had the highest number of species of Brinckiella, which is likely related to the vast diversity of plant that they are associated with and probably feed on. In the Succulent Karoo the distribution of Brinckiella might be associated with seasonal plants that occur in the spring and at the beginning of summer. The genus may be monophyletic, and it split from the common ancestor shared with Holochlora fruhstorferi Carl, 1914 about 14.2 Mya, and it split again from the common ancestor shared with Isophya major Brunner von Wattenwyl, 1878, Phaneroptera gracilis Burmeister, 1838 and Kuwayamaea chinensis (Brunner von Wattenwyl, 1878) at 10.16 Mya and diverged in the late Miocene around 8.79 Mya, producing two main clades (A and B). Clade A diverged 7.85 Mya and is composed by two closely related species: B. aptera and B. mauerbergerorum, while Clade B diverged 7.24 Mya and gave rise to two lineages (L1 and L2). Brinckiella wilsoni constitutes L1, and L2 split later in the early Pliocene around 4.74 Mya, and is represented by two sister species, B. arboricola and B. sp. n. 5.
Open Access
Flame and fodder: how fire and grazing shape arthropod communities in the Okavango Delta
(2023) Grobler, Michiel; Janion-Scheepers, Charlene
The documentation of species presence and distribution is essential for the conservation of biodiversity worldwide. Invertebrates are relatively understudied compared to vertebrates, globally and within the southern African region. This is especially true for developing countries, due to accessibility, costs associated with remote fieldwork and lack of taxonomic expertise. Nevertheless, southern Africa is highly diverse in fauna and flora, and many species still are undescribed in many of the countries in this region. In Botswana, the Okavango Delta is an exceptionally unique biological system with a vast wetland in the middle of the Kalahari basin, acting as one of the only consistent water resources. The complexity of this flood-driven system is not only due to seasonal influxes from the catchment area in central Angola, but also due to the slow drop in elevation, which causes complex channels, streams, bogs and other aquatic habitats to form as the delta fans out towards the Makgadikgadi pans. At the core of this critical hydrological system lie aquatic and terrestrial systems and processes that ensure its continued functioning and overall health, with many of these services underpinned by invertebrates, arthropods in particular. Although the aquatic invertebrates are relatively well-studied, the terrestrial arthropods have received less attention, while undoubtedly also providing critical regulatory services on the islands within the Delta, and along the edges. As a World Heritage Site, the Okavango Delta should be prioritised for research related to ecosystem processes and monitoring of the smaller faunistic “cogs” that ensure the collective functioning of the overall system, especially due to the threats it faces. Anthropogenic disturbances have become more common and regular along the edges and within the Okavango Delta over the last few decades, and as such, human-induced fire and livestock grazing has increased the pressure on the natural systems in which it occurs. Given the fragmented knowledge of terrestrial arthropods within Botswana, and the Okavango Delta specifically, this study aimed to compare arthropod communities between ongoing disturbance regimes, using a multi-taxon approach. Specifically, this study aimed to: 1) compare the diversity and abundance of four terrestrial arthropod groups (ants, wasps, springtails and spiders) in burnt and grazed sites, 2) investigate whether burning or grazing have impacts on arthropod diversity, in terms of species richness and abundance, 3) provide a starting point dataset to monitor the impact of disturbances on arthropod communities in the Okavango Delta into the future, 4) generate starting point species inventories for these four taxa in this region, and 5) compile an updated species list of the spiders (Araneae) of Botswana. Using pitfall traps and litter extractions across two seasons, the abundance of the four groups was only fractionally higher in the wet season for the pitfall traps, but litter extractions had large increases in ants, springtails and wasps in the wet season. Ants had the most species and the highest diversity in the grazed sites compared to burnt sites, while Collembola and Araneae communities were more even in the burnt sites than in the grazed sites. Species richness, evenness and diversity varied between trapping methods and between groups studied, illustrating the varied responses of arthropod communities to disturbances. Ants and Collembola varied significantly between seasons, but not between disturbance types, while wasps and spiders differed significantly between both season and disturbance types. This study created the first starting point dataset for comparing the impacts that disturbances have on arthropod community shape and composition. An up-to-date species list for spiders of the Okavango Delta was compiled, adding 37 new records to the existing species list. From pitfall traps and litter extractions a total of 20 families and 51 genera were sampled, with 40 species identified. From active collections, a total of 18 families, 55 genera and 70 species were collected. The updated species list of spiders in the Okavango Delta contains 33 families, 141 genera and 220 species. This will serve as the basis for further species inventories and diversity studies in the region. It is recommended that terrestrial arthropod research be continued within this World Heritage Site to ensure the documentation of the diversity of species present here, but also to utilize these species as indicators for ecosystem changes to ensure the continued survival of this wetland and the species that depend on it.
Open Access
How rewilding impacts ecosystem health in a semi-arid region
(2025) Faria, Alexandro Carlos; Janion-Scheepers, Charlene; Hawkins, Heidi; Midgley, Guy
Rewilding represents more than just the reintroduction of iconic charismatic species; it holds the potential to assist in reestablishing critical ecosystem functions, helping create dynamic, resilient, and self-sustaining ecosystems. Here I test the general idea that the reintroduction of megafauna such as elephant, rhino, and buffalo will alter soil and vegetation characteristics as well as dung beetle assemblages via megafauna trampling and feeding behaviours, ultimately improving ecosystem health. This was conducted in two different vegetation types, Montagu Shale Renosterveld and Western Klein Karoo. By examining these key indicators of ecosystem health, this research has revealed that the rewilded areas generally exhibit higher levels of dung beetle abundance (up to 3.7 times higher than livestock areas), improved soil dynamics (e.g. 11–12% lower bulk density), and greater vegetation productivity as shown by EVI trends. The study also investigated the potential of leveraging carbon credits as a means to fund restoration projects in semi-arid settings, but ultimately concluded that a more nuanced approach is likely needed in the form of biodiversity credits. Ultimately, this study provides tentative evidence that well-managed rewilding can indeed assist in restoring degraded landscapes. This, in turn, reaffirms the crucial role of nature-based solutions in biodiversity conservation and highlights the importance of positive land stewardship and management. These findings underscore the importance and viability of embracing rewilding as a legitimate method by which to protect and regenerate degraded landscapes. In addition, this study illustrates how the impact of rewilding is not uniform across ecosystem types by comparing findings between the two stated vegetation types. All these findings suggest that a more holistic approach is needed to evaluate and value rewilding initiatives, one which includes key ecological variables such as vegetation dynamics, various soil characteristics, and insect populations. By taking an interdisciplinary approach to conservation through combining rigorous ecological assessments with innovative financing mechanisms (such as biodiversity credits) in the future, it is more likely to capture the multifaceted benefits of rewilding and foster long-term ecosystem resilience. This comprehensive strategy is pivotal for transforming biodiversity conservation and ensuring robust ecological recovery across diverse landscapes, while increasing the likelihood of financial viability and sustainability of rewilding projects.
Open Access
Intergrative taxonomy and biogegraphy of ants in the genus Anoplolepis (Hymenoptera: Formicidae) in Southern Africa
(2022) Ndaba, Abusisiwe; Janion-Scheepers, Charlene; Mbanyana-Nhleko, okuthula; Munyai, Caswell; van Noort, Simon
Taxonomy has played an important role in biodiversity assessments. It provides an understanding of biodiversity components, data that are essential for making decisions on conservation and sustainable use and is also a foundation for phylogenetic studies. Although this field of study has played an important role in identifying and describing biodiversity, the issue of cryptic species has posed many taxonomic challenges. In most taxonomic groups, species with subtle differences and high intraspecific variation are often misidentified when morphological data is not supported by other methods, for example, genetic data. The genus Anoplolepis is one of several polymorphic groups of ants. Although this genus is widely distributed in the Afrotropical region, it is understudied. This study aimed to: 1) resolve taxonomic challenges of the ant genus Anoplolepis in southern Africa, including the production of updated identification keys for the species and the description of new species; 2) resolve taxonomic challenges of the ant genus using molecular data; 3) to understand and update the geographical distribution of species within Anoplolepis; 4) verify the existing distributional records for the invasive species, A. gracilipes in South Africa and monitor the main introduction pathways; and 5) to assess the overall changes in ant assemblages of ants collected between harbours and provinces and test the effectiveness of the pitfall trapping and baiting method in sampling ants. Material from various institutions and organisations were used to conduct this study, as well as new material collected. By using a combination of traditional morphological taxonomy and DNA barcoding, a total of 16 species were identified. Of these, 11 species were determined using morphological features and phylogenetic analysis based on molecular data, with the five remaining species being identified using only morphological features. Based on morphological assessment, one species (Anoplolepis sp. nov. 12) was deemed to be new to science. This study showed that the DNA barcoding method (CO1) was not efficient to delimit some of the species in this genus, highlighting the need to prioritize more fine-scale molecular markers, especially when working with polymorphic or cryptic species. Overall, the distribution of species in this genus shows that this genus is widely distributed across southern Africa. The invasive species A. gracilipes was not detected across all the sampled harbours, nor from any of the material housed at the Iziko Museums of South Africa, loaned from other institutions and organisations in South Africa and other countries used for this study. This is a positive outcome for conservation authorities. This species is highly invasive elsewhere in the world, and if introduced outcompetes native fauna and may result in ecosystem collapse. Although A. gracilipes was not detected in the samples from this study, early detection and eradication of this species should be prioritized. This can be done through existing pest monitoring programs at harbours, and thorough biosecurity measures. This study contributed to developing scarce skills such as the taxonomic identification and the descriptions of new species, increasing the barcoding database of ants in South Africa, and the overall revision of this economically and ecologically important ant genus.
Open Access
Target strength of bat prey in relation to pulse frequency and vegetation density in bat species, Rhinolophus fumigatus (Rüppell's horseshoe bat)
(2023) Freeks, Micaela; Janion-Scheepers, Charlene; Jacobs, David
The relationship between echolocation and morphology is evident in several insectivorous bat species where a negative correlation between peak echolocation frequency and body size is observed. However, there are various exceptions to the general allometric relationship observed between body size and echolocation pulse frequency of both low-duty cycle and high-duty cycle bats. One such example in high duty-cycle bats is Rhinolophus fumigatus, where east African populations echolocate at a frequency of 55.1 ± 1.5 kHz, lower than that predicted by its body size (12.7 ± 0.9 g). The foraging habitat hypothesis states that a deviation from the allometric relationship between pulse frequency and body size is related to the foraging habitat and foraging style of the species and predicts a negative relationship between peak echolocation frequency and wing loading. Lower echolocation frequency penetrates dense vegetation more effectively than higher frequency pulses, resulting in greater energy for the generation of audible target strengths from the insect prey. Furthermore, a small body size allows manoeuvrable flight which is required for foraging in dense vegetation. The combination of low echolocation frequency and small body size, which represents a deviation from allometry between frequency and body size may be an adaptation for detecting and capturing, respectively, insect prey in dense vegetation. The target strengths produced by Rhinolophus fumigatus_East, Rhinolophus fumigatus_West (a sister lineage with a larger body size (18.8 ± 1.5 g) and similar echolocation frequency (55.1 ± 1.5 kHz)), and Rhinolophus capensis (a species of similar body size (12 ± 1.7 g) but higher echolocation frequency (84.8 ± 3.6 kHz) were measured in three relative vegetation densities and compared to determine if the deviation of Rhinolophus fumigatus_East from the general allometric relationship can be explained by the foraging habitat hypothesis. Moths were ensonified with semi-synthesized echolocation calls of the three bats in sparse, moderate, and dense vegetation densities and the returning echoes measured using Avisoft SASLab Pro. Target strengths were then calculated after accounting for atmospheric attenuation and non-parametric tests were conducted as the data did not meet the requirements for parametric tests, even after normalisation techniques were applied. Within lineage and species analysis showed no significant difference in target strength between the three vegetation densities. Between lineage and species analysis showed a significant difference between Rhinolophus fumigatus_East and Rhinolophus capensis in all three vegetation densities, for both high (HDC) and low duty cycles (LDC). However, within the series of various tests (where each lineage and species pulses were played consecutively) a significant difference exists between both R. fumigatus lineages and with R. capensis for both HDC and LDC pulses. In the series of natural pulses, a significant differences was found to exists between R. fumigatus_West and R. capensis for HDC pulses, and R. fumigatus_East and R. capensis for LDC pulses. When combining all the HDC and LDC data, a significant difference was found between R. fumigatus_East and R. capensis, and R. fumigatus_West and R. capensis. The results of the study do not support the foraging habitat hypothesis, and this may be due to Rhinolophidae being clutter forage specialists. Their echolocation pulses are already suited for clutter foraging and any slight deviations are unlikely to confer any additional benefit in prey detection. Allopatric divergence may explain R. fumigatus_East's deviation in echolocation frequency where extended periods of geographic isolation lead to natural and sexual selection on signalling systems (the sensory drive hypothesis) which allowed speciation to occur. Alternatively, R. fumigatus_East's deviation may also be caused by phenotypic plasticity as well as genetic differences. Additionally, this may have important implication for intraspecific communication, where studies have shown the role that echolocation plays in communication in bats. Other morphological traits may be better predictors of echolocation frequency (i.e., nose-leaf width, pinna size, and cochlea size) and although other studies have produced varied results, this provides avenues for further research.
Open Access
The effects of urbanisation on bee and wasp communities in Cape Town, South Africa
(2022) Walker, Gemma; Janion-Scheepers, Charlene; Brom, Peta; O'Farrell, Patrick
Bees and wasps provide essential regulatory ecosystem services by pollinating urban plants. However, there are massive global declines in many insect groups, and little is known about the impacts of urbanisation on pollinators in rapidly developing areas of Africa. South Africa is one of the most urbanised and biodiverse countries in Africa, and the Cape Floristic Region, one of the country's most important centres of biodiversity, is the only area in the world where bee and plant diversity hotspots coincide. Within the centre of this hotspot (Durbanville, Cape Town), I investigated the effects of urbanisation and availability of floral resources on bee and wasp (pollinator) diversity, community composition, and nesting guild distribution across an urbanrural/natural gradient. Using pan traps, specimens were collected from 18 sites in the austral spring of 2019 and 2020. A total of 433 bee and 45 wasp specimens, comprising of 45 bee and 27 wasp morphospecies respectively, were collected. Bees from the family Halictidae (particularly Seladonia and Patellapis species) were the most abundant. Except for Apis mellifera, all other bee species were solitary, and most (86.7%) collected pollen from flowers. A total of four different nesting guilds were identified, with the most common being ground-nesters (68.9%). Floral resources, rather than the degree of urbanisation, had a strong positive effect on pollinator diversity and community composition. The same trend was observed for nesting guilds at both the community and individual guild level. This study supports the development of several costeffective and achievable conservation initiatives, such as adopting no-mow periods during austral spring and developing small-scale bee-friendly floral-rich patches, which can be undertaken by existing municipal structures and private landowners alike. Urban spaces in Cape Town have the potential to support important pollinator diversity, but more research is needed. Suggested future studies include investigating the ways pollinator diversity and community composition is influenced by 1) individual floral species and characteristics, 2) the size, shape, and location of habitat/floral patches, and 3) the effects of urban warming.

Browsing by Author "Janion-Scheepers, Charlene"

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