Browsing by Author "Brom, Peta"

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    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.
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    There might be a frog in McElligot's Pool: a study of the habitat characteristics and social factors associated with amphibian presence in urban residential gardens in a suburb in Cape Town
    (2017) Brom, Peta; Anderson, Pippin; Underhill, Leslie G; Channing, Alan
    This thesis engages with urban ecology through the lens of garden amphibians within a community in Cape Town. The study explores habitat and maintenance features associated with amphibian presence and the social processes underpinning attitudes towards amphibians, with the aim of strengthening knowledge underpinning the "what" (knowledge of natural requirements), "Why" (social drivers for urban landscape form and management), and the "how" (working with people, for garden biodiversity initiatives. To explore the "Why" component, a social survey was conducted with 192 members of the community. One‐way anova and correspondence analysis were used to explore the relationship between values, culture, knowledge and memories of early childhood experiences against a general attitude towards frogs and toads. The findings are consistent with the theoretical framework of Connectedness To Nature where positive attitudes are supported by normative values, cultural beliefs, knowledge and positive experiences with care‐givers and role‐models. The garden habitat component of the study sought to explore the technical questions of the "What" requirement for amphibian presence in gardens. It was loosely based on the BIMBY tool with adaptations for context and targeted species. 50 gardens were visited and surveyed. They were divided into two groups for comparison: Those in which residents reported amphibian presence, and those which did not. Results indicate that the cape river frog (A. fuscigula) and clicking stream frog (S. grayii), are attracted to gardens with moderate to dense vegetation at groundcover level. Gardens with moderately planted beds were more likely to report frogs if they had additional resources, in particular, ponds and mulch. The "How" question brought together the two themes in a discussion on citizen mobilization and ways in which community groups are successfully implementing urban ecology conservation and reconciliation strategies. This work is important for urban nature conservation which seeks to engage private land‐owners (garden enthusiasts) and community and citizen groups in implementing urban biodiversity projects.