Aspects of the ecology and behaviour of a potential urban exploiter,the southern tree agama,Acanthocercus atricollis

Urbanisation has caused significant alterations to ecosystems, generally resulting in decreased biodiversity. However, certain animal species persist and thrive in urban environments by making use of available opportunities, anthropogenic resources, infrastructure and increased ambient and surface temperatures. These species are known as urban exploiters. We investigated the southern tree agama, Acanthocercus atricollis population trends, habitat use and basking and shading behaviour in a high-density urban human-populated housing metropolitan area in Pietermaritzburg, KwaZulu-Natal, South Africa. We marked individual southern tree agamas to determine habitat use and territories (n?=?37). The southern tree agama population density was high, and they had established set territories here. We conducted monthly observations (February 2017–July 2017 and March 2018–February 2019) to determine the degree of basking and shading behaviour with season and time of day and location. Southern tree agamas invested more than half of their time (57%) in basking behaviour during the overall observational study period. Basking and shading patterns changed with season and time of day. The number of basking southern tree agamas decreased during winter and basking commenced later. We found that increased anthropogenic infrastructure and supplementary food availability, decreased predators, and basking opportunities could have had an influence on their population increase and that the southern tree agama is a potential urban exploiter.

     

Hadeda Ibis (<Emphasis Type="Italic">Bostrychia hagedash</Emphasis>) urban nesting and roosting sites

Hadeda Ibis (Bostrychia hagedash) have increased in population size and expanded in range in South Africa possibly as a result of increased use of exotic trees for nesting and roosting in urban areas. We investigated the urban nesting and roosting sites of the Hadeda Ibis by measuring tree height and species used by Hadeda Ibis for nesting and roosting in Pietermaritzburg, KwaZulu-Natal, South Africa. We expected Hadeda Ibis nests and roosts to have habitats, like wetlands, to be within 10 km of the roost or nest tree. Hadeda Ibis nest and roost locations were mapped using ArcGIS and available resources (grasslands, wetlands, plantations, other natural water sources) 10 km around each roost and nest tree were determined. Results showed that Hadeda Ibis use exotic trees for nesting and roosting in urban areas more than indigenous trees. This may be because exotic trees are more available in urban environments, particularly those trees that have ornamental value. Hadeda Ibis did not nest and roost closer to expected resources. Although previously associated with wetlands, Hadeda Ibis in urban environments were not close to natural water sources. This can be explained by swimming pools providing accessible drinking water and well watered lawns providing suitable foraging habitat therefore allowing them to roost and nest in this urban habitat.     

A citizen science survey: perceptions and attitudes of urban residents towards vervet monkeys

A diversity of indigenous and alien wildlife persists in suburbia, and provides residents with the opportunity to experience wildlife. Suburban gardens may serve as refugia and foraging grounds for many primate species allowing them to populate within a largely urbanized landscape. However, this has led to the increasing human interactions with them, resulting in conflict. Our study investigated the perceptions of suburban residents towards urban vervet monkeys Cercopithecus aethiops pygerythrus within the Msunduzi and Ethekwini municipalities, KwaZulu-Natal, South Africa. We assessed how these related to the monkeys’ presence, activities and interactions in residential gardens, and the value of wildlife to residents. Assessment was conducted through an online questionnaire survey. General attitudes of residents to vervet monkeys were canvassed by assessing the respondents’ level of active engagement in wildlife watching within their properties. We analyzed 603 surveys submitted online using logistic regression and ordinal regression models. We ascertained that vervet monkeys were disliked by 29% of residents due to their aggressiveness, destructive behaviour in gardens and households, and perceived threat to native wildlife. Frequency and duration of foraging vervet monkeys in residents’ gardens was influenced by the presence of pet dogs, fruiting trees, tall trees (>2 m), ratio of indigenous to alien vegetation of gardens, residency type, and active and passive food provisioning. Despite conflict, the majority of respondents appreciated urban wildlife (67%) and actively engaged in wildlife watching (88%), emphasizing the importance of incorporating human dimension values into the management of urban biodiversity. Our study highlights the value of citizen science in providing mechanisms for identifying priority management and conservation efforts at the highly complex human-wildlife interface in an urbanized landscape.     

Hadedas in the hood: Hadeda Ibis activity in suburban neighbourhoods of Pietermaritzburg,KwaZulu-Natal,South Africa

Urban environments are a combination of green and grey spaces and although many species are unable to live in these transformed areas there are some that can use urban features to benefit their persistence here. The Hadeda Ibis (Bostrychia hagedash) is one such species and this study investigated the urban activities of these birds. Five suburbs of Pietermaritzburg in KwaZulu-Natal, South Africa were surveyed for Hadeda Ibis engaged in flying, foraging, perching and calling behaviours. Each suburb differed in the degree of urbanisation and we expected that their morning activity would differ accordingly. A difference in Hadeda Ibis calling, foraging and flying activity between summer and winter was also expected because of seasonal rainfall patterns. Although Hadeda Ibis were more common in suburbia than the city centre in Pietermaritzburg, they occurred throughout. More were observed calling in summer than in winter probably because of changes in distribution during the breeding season with more family groups of two or three individuals. There was no significant difference in Hadeda Ibis flock size when comparing foraging during summer with winter despite greater summer rainfall. Also there was no significant difference in flock size with flying activity for both seasons nor suburb although it was expected that Hadeda Ibis would need to travel further during winter and from suburbs with more grey space to access ideal foraging areas. Hadeda Ibis need moist soil to forage effectively and in an urban environment short grassed, well watered lawns provided an ideal foraging habitat regardless of season. Hadeda Ibis used urban structures like house roofs, poles, pylons, and fences for perching but continued to roost in trees so while they are able to use urban features, they still rely on a certain degree of green space for urban persistence.     

Depleted suburban house sparrow <Emphasis Type="Italic">Passer domesticus</Emphasis> population not limited by food availability

Little is known about the environmental factors that limit the demography and abundance of wild vertebrates in highly modified urban environments. The House Sparrow Passer domesticus is a globally widespread species whose urban populations have recently undergone substantial declines particularly in Europe. The environmental drivers of these declines remain unknown. In a previous study we showed that invertebrate availability during the breeding season limited reproductive success but not population size in a suburban sparrow population. In this study we test experimentally whether year-round food availability limits demography and population size. Supplementary feeding involved the provision of invertebrate prey (during the breeding season) plus unlimited high-energy seed (year-round) at 33 sparrow colonies spread across suburban London over two successive calendar years. Thirty-three unfed colonies served as controls. Supplementary feeding increased fledgling abundance, but had no impact on overwinter survival or population size. We conclude that this depleted suburban sparrow population is not limited by food availability, and conservation efforts based primarily on food provision are unlikely to succeed. We also tested whether cross-colony variation in sparrow abundance was correlated with a set of potential environmental stressors including measures of predator abundance and pollution. Sparrows were more abundant, or showed more positive temporal changes in abundance, at localities containing large areas of seed-rich habitat and low levels of nitrogen dioxide air pollution. Further research is merited into the potential impacts of air pollution on the fitness of urban birds.     

Home range and habitat use of feral cats in an urban mosaic in Pietermaritzburg,KwaZulu-Natal,South Africa

Feral cats (Felis catus) are one of the world’s worst invasive species with continuing expanding populations, particularly in urban areas. Effects of anthropogenic changing land-use, especially urbanisation, can alter distribution and behaviour of feral cats. Additionally, resource availability can influence home range and habitat use. Therefore, we investigated home range and habitat use of feral cats (n?=?11) in an urban mosaic with varying degrees of urbanisation and green spaces in Pietermaritzburg, KwaZulu-Natal, South Africa. Using global positioning cellular trackers, individual feral cats were followed for a minimum of six months. Minimum convex polygons (MCP) and kernel density estimates (KDE) were used to determine their home range, core area size, and habitat use. Mean home range (± SE) for feral cats was relatively small (95% MCP 6.2?±?4.52 ha) with no significant difference between male and female home ranges, nor core areas. There was individual variation in home ranges despite supplemental feeding in the urban mosaic. Generally supplemental resources were the primary driver of feral cat home ranges where these feeding sites were within the core areas of individuals. However, the ecological consequences of feeding feral cats can increase their survival, and reduce their home ranges and movement as found in other studies.     

Ecosystem services of urban green spaces in African countries—perspectives and challenges

The concept of ecosystem goods and services is increasingly used to describe how biodiversity and ecosystems are linked to human well-being and that it should be placed at the core of sustainable urban development. Predictions of a tremendous future increase of urbanization in Africa necessitate an investigation into the research on ecosystem goods and services in the urban green infrastructure of Africa. Ecosystem goods and services (ES) are described as the benefits humans derive directly or indirectly from ecosystem functions and are classified as supporting, provisioning, regulating and cultural services. A literature study focusing on journal papers was conducted. Additionally a case study based on two masters studies was further refined. ES studies in African cities are biased towards South Africa and include assessments and economic valuations in which several different methods were used to determine direct consumptive and non-consumptive and indirect use values. Emphasis was placed on the multifunctional nature of ES. The main objectives of these studies were to sensitize policy makers, planners and the general public about the importance of biodiversity and ES. Ecosystem-based adaptation is discussed as the most appropriate approach in terms of applying knowledge about ES and their values in African cities as many residents still rely on ES from natural areas, but the major ecological, economic and political challenges are acknowledged. A case study focusing on domestic gardens (private green spaces) have indicated that the demand and supply of certain ES differ along a socio-economic gradient due to poor service delivery and smaller plots in the poorer areas mainly due to the legacy of separate development of the past. Where provisioning services are mainly outsourced in cities, it was found that plant species useful as food, medicine, etc. were more frequent in the gardens of poorer residents than in those of more affluent areas. The tendency to pay more for residential properties close to public open spaces, as in Europe, could not be statistically proven in the more affluent areas of a South African city, although the property values in proximity of public open spaces in some of the areas studied were lower than further away.     

The influence of anthropogenic resources on multi-scale habitat selection by raccoons

With the continuing spread of urban areas, gaining a greater understanding of the effect of human presence on wildlife species is essential for wildlife managers. We determined the influence of anthropogenic resources on home range size and habitat selection of raccoons (Procyon lotor) during summer (June–August) 1996–2000 for 120 raccoons at three sites exposed to varying levels of urbanization and anthropogenic resources, specifically food. Home range estimates were larger (P < 0.05) at the rural site than the suburban and urban sites for both genders. We used compositional analysis to examine raccoon habitat selection at the second-order home range, second-order core area, and third-order home range scales. Woodland was consistently a highly-selected habitat type for both sexes at every spatial scale. Relative to other habitat types, habitat associated with human-related food (human use areas) was selected most often at the urban site, intermediately at the suburban site, and not selected at the rural site. Spatial scale also affected habitat selection. Human use areas were preferentially selected at the second- and third-order level at the urban site, third-order level only at the suburban site, and at neither level at the rural site. Additionally, intersexual differences in habitat selection were reduced at the urban site, with both sexes preferentially selecting for human use areas as well as woodland habitat. Smaller home ranges in urbanized environments are often attributed to the abundant and concentrated anthropogenic resources associated with human activity, but with little empirical support. Our habitat selection analyses followed our predictions that raccoon foraging is strongly influenced by the artificial distribution and abundance of human-related food. Male and female raccoons in urban areas reduce their foraging patterns and focus their foraging activity on anthropogenic foods.     

South‐South Migration and Urban Food Security: Zimbabwean Migrants in South African Cities

The drivers of food insecurity in rapidly‐growing urban areas of the Global South are receiving more research and policy attention, but the precise connections between urbanization and urban food security are still largely unexplored. In particular, the levels and causes of food insecurity amongst new migrants to the city have received little consideration. This is in marked contrast to the literature on the food security experience of new immigrants from the South in European and North American cities. This article aims to contribute to the new literature on South‐South migration and urban food security by focusing on the case of recent Zimbabwean migrants to South African cities. The article presents the results of a household survey of migrants in the South African cities of Cape Town and Johannesburg. The survey showed extremely high levels of food insecurity and low dietary diversity. We attribute these findings, in part, to the difficulties of accessing regular incomes and the other demands on household income. However, most migrants are also members of multi‐spatial households and have obligations to support household members in Zimbabwe. We conclude, therefore, that although migration may improve the food security of the multi‐spatial household as a whole, it is also a factor in explaining the high levels of insecurity of migrants in the city.     

The natural South Florida system II: Predrainage ecology

The goal of the South Florida restoration process is to reestablish a sustainable ecological system that approximates the predrainage system (i.e., the system that existed before canals and water control structures were built). A critical step in the restoration process is to describe the predrainage system with sufficient detail to capture the essential landscape features (e.g., space, connectivity, patterns) that gave the region its defining character and supported its natural abundance and diversity of plants and wildlife.A previous attempt at reconstruction of predrainage (circa 1870) vegetation patterns covered only the Everglades (Davis et al., 1994) but introduced a concept of landscape mosaics that should be extended to South Florida. We propose 16 landscape units that include freshwater landscapes, upland landscapes, coastal wetlands, and estuaries (particularly Florida and Biscayne Bays), the Florida Keys and Reef Tract, and the Inner Southwest Florida Shelf.The predrainage area, because of its enormous size, supported a landscape heterogeneity that was advantageous to animals with several distinct habitat-related life strategies. Five species have been selected to illustrate different dependencies on landscape patterns in predrainage South Florida: wood stork (Mycteria americana), American alligator (Alligator mississippiensis), snail kite (Rostrhamus sociabilis), Cape Sable seaside sparrow (Ammodramus maritimus mirabilis), and pink shrimp (Penaeus duorarum). As individuals or as populations, these animals operated across several spatial and temporal scales. The predrainage system's large spatial extent and complex hydropatterns allowed wood storks and other animals with large feeding ranges to take advantage of the strongly seasonal rainfall pattern, while at the same time providing a refuge somewhere in the system for survival of all other species. Landscape heterogeneity and large spatial extent promoted the region's natural wildlife abundance and species diversity.     

Spatial patterns of female Ailanthus altissima across an urban-to-rural land use gradient

Ailanthus altissima is an invasive, dioecious deciduous tree common at the interface between urban and rural areas in the mid-Atlantic region, U.S.A. To examine spatial patterns of abundance and associations with land use type, we mapped all mature female trees in nine 89.5 ha plots (805.5 ha total area) across a typical urban-to-rural land use gradient using aerial images obtained via remote sensing supplemented by detailed ground referencing. Rural plots were dominated by forest and had the lowest density of mature females (0.007 females ha⁻¹); urban and suburban plots did not differ significantly in mean density (0.37 females ha⁻¹ vs. 0.34 females ha⁻¹, respectively). Individuals in urban plots were more evenly distributed, but were not associated with a wider variety of land uses and were closer to roads or openings than those in suburban plots. Given less available habitat per unit area in urban than in suburban environments, these patterns suggest that Ailanthus fits the profile of an invasive species that may be proliferating outward from urban centers. With continued disturbances associated with development in the suburban areas, and timber harvesting in the rural areas, further spread of Ailanthus seems likely.     

Homestead greening is widespread amongst the urban poor in three medium-sized South African towns

Trees in urban areas are important sources of ecosystem services and benefits. In most towns the bulk of urban biodiversity, and trees specifically, are found in homestead gardens. But there is only limited understanding of the tree holdings in such gardens, and how they vary within and between towns, especially for developing countries where rapid urbanisation and high poverty influence the use of and reliance on land and local resources. We report on the nature of tree holdings in private gardens of poorer suburbs in three medium-sized towns along a gradient of decreasing mean annual rainfall in northern South Africa. A total of 3 217 trees were enumerated across 450 randomly selected homesteads. Most (90 %) households had at least one tree on their homestead, with an average of 7.7?±?6.1 trees. Most householders had planted the trees themselves. The density of trees declined along the moisture gradient. Within towns, tree density was positively related to garden size, which in turn was related to relative affluence and age of the suburb. Newer and poorer suburbs had the fewest trees per household. Sixty-two tree species were recorded, which were dominated by alien species, especially fruit trees. There was no relationship between the moisture gradient and tree species richness per household, but within towns there was a difference between suburbs, being lowest in the newest suburbs. Numbers of trees and species per household was positively related to age of the household head.     

The impact of urbanisation on avian species: The inextricable link between people and birds

This study investigates the impact of urbanisation on birdlife in a major city. Line transects and point counts were used to survey birds in three habitat types: parkland, residential areas and business/industrial areas. Abundance, richness and diversity of assemblages were determined for all bird species and for those birds native to the area. Behaviours of birds, and of human residents in relation to birds, in these urban areas were documented, including all instances of avian aggression. Bird species, including a subset of native bird species, have greater abundance and richness in parklands. Overall species diversity is greatest in residential habitat types, but native diversity is greatest in parklands. Introduced species are most abundant in business/industrial habitat types. The most frequent aggressive encounters were initiated by noisy miners Manorina melanocephalas, one of the four most common species throughout all habitat types (other common species include the rainbow lorikeet Trichoglossus haematodus, rock dove Columba livia and common myna Sturnus tristis). Other behaviours involved birds utilising food and roost resources and were classified as being caused by active and passive human behaviours. These outcomes indicate that local changes to the environment can impact the bird species by providing different food and roost resources. Human residents and local governments have a range of tools to modify the diversity of urban areas. Further research is needed to determine alternative definitions of modification, such as defining it as open space, and investigating the health of the avian populations in urban areas.     

Gambling Participation and Problem Gambling Severity among Rural and Peri-Urban Poor South African Adults in KwaZulu-Natal

Poor South Africans are significantly poorer and have lower employment rates than the subjects of most published research on gambling prevalence and problem gambling. Some existing work suggests relationships between gambling activity (including severity of risk for problem gambling), income, employment status and casino proximity. The objective of the study reported here is to establish the prevalence of gambling, including at risk and pathological gambling, and the profile of gambling activities in two samples of poor South African adults living in a rural and a peri-urban community. A total of 300 (150 male, 150 female) adults in KwaZulu-Natal, South Africa in communities selected using census data, completed the Problem Gambling Severity Index and a survey of socioeconomic and household information, and of gambling knowledge and activity. It was found that gambling was common, and—except for lottery participation—mostly informal or unlicensed. Significant differences between rural and peri-urban populations were found. Peri-urban subjects were slightly less poor, and gambled more and on a different and wider range of activities. Problem and at risk gamblers were disproportionately represented among the more urbanised. Casino proximity appeared largely irrelevant to gambling activity.     

Attitudes to Food Gardening from a Generational Perspective

Abstract

The paper sheds light on why older gardeners want to grow their own food and younger people do not. Only since the coming of democracy in 1994 has the potential of food gardens attracted the attention of South African development practitioners and policy makers. Sustainable food garden projects build on a culture of gardening that has its roots in rural subsistence farming. While food gardens were commonly regarded as a tool for rural development, rapid migration to the cities has introduced urban cultivation as a strategy to provide food and income security for the urban poor. This case study reports in-depth discussions with twenty active older gardeners in a small town in the predominantly rural Eastern Cape Province of South Africa. The highly motivated gardeners cited reasons for growing food that went beyond basic needs for food security and livelihoods and included aesthetics, morality, and health and well-being. However, they attributed mainly negative attitudes to the younger generation that aspires to a modern lifestyle which excludes food gardening. Follow-up group interviews with young people confirmed these attributions. The discussion focuses on intergenerational transmission of values and its implications for sustainable community development.     

The scorpions of the urban habitat of Rome (Italy)

A review of the scorpions (three species of the genus Euscorpius, family Chactidae) found in the urban habitat of Rome, Central Italy, together with an analysis of the factors which affect their distribution and abundance in the town, is pointed out. It appears that Euscorpius carpathicus, a species commonly found on limestone terrains in Latium, is frequent, though not particularly abundant, in the urban area of the city especially along the course of the Tiber River. It appears that Euscorpius flavicaudis, a species commonly found on volcanic terrains in Latium and the most common terrains in and around the area of Rome, is the most common species in both the urban and suburban areas of the city. It appears that Euscorpius italicus, a species common in north and northeastern Latium, is represented, in the sample of the scorpions of the city, by a single, possibly aberrant, specimen.     

Predation of artificial bird nests in suburban gardens of KwaZulu-Natal,South Africa

As urbanization increases, the identification of nest predators becomes important for avian conservation and management of urban wildlife communities. We investigated bird nest predation using artificial nests in urban areas of the KwaZulu-Natal (KZN) Province of South Africa. From June 2013 through February 2014 we installed seventy-five artificial nests in 25 suburban gardens in the Ethekwini and Msunduzi municipalities of KZN. Euplectes spp. nests were used and baited with two quail-sized, hand-made, silicon eggs. These were placed in residential gardens and monitored by camera traps for 2-weeks in winter, spring and summer respectively. Generally bird nesting occurs throughout the year in KZN’s subtropical climate, with some avoidance during the autumn season. Therefore, experiments were not conducted during autumn, as fresh nests were not available for use. Overall the rate of predation on artificial nests was 25 % (n = 19), with vervet monkeys Ceropithecus aethiops pygerythrus predating 20 % (n = 17) of the nests while domestic cats Felis catus predated 3 % (n = 2) of nests. Nest predation was significantly higher in the winter season, with 79 % of depredations occurring in winter (n = 15), 16 % in spring (n = 3) and 5 % in summer (n = 1), and in areas with less canopy cover. Our results suggest that vervet monkeys may have a negative impact on nesting birds in urban environments, however, in order to assess the rate of predation experiments on natural nests coupled with information on fledgling success is deemed necessary to investigate avian population declines.     

Augmented informality: South Africa's backyard dwellings as a by-product of formal housing policies

Insufficient and inadequate housing for the urban poor has a long history in South Africa, as in other African cities. Nearly one-fifth of urban households in South Africa reside in an informal dwelling. While most live in informal settlements, significant proportions have erected informal structures (essentially ‘shacks’) in the backyard of another property, a distinctly South African phenomenon. Backyard dwellings have historically been overlooked by housing policies that focus on upgrading and/or eradicating informal settlements. Previously, backyard dwellers were perceived as marginalised, living in appalling conditions and exploited by cavalier landlords. However, the post-apartheid provision of state-funded housing for the poor has altered the nature of backyard housing, creating a new class of cash-poor homeowners who are dependent on income from backyard dwellers' rent, thus ensuring a more equitable power pendulum between landlord and tenant. This paper uses research conducted in a low-income state-subsidised housing settlement in Cape Town to explore the new dimensions of informal backyard housing, both for landlords and tenants, as a consequence of South Africa's formal housing policies.     

Vascular plants along an urban-rural gradient in the city of Tampere,Finland

The aim of this study was to analyse the spatial distribution of vascular plants along a 21-kilometre rural–urban–rural transect in the city of Tampere, Finland. The study emphasised the distribution of native and non-native species, both in absolute numbers and proportionally. The observed differences are explained by the share of forest land, the number of detached houses, distance from the city centre, and human population. Non-natives showed the highest values in suburban areas. Still, the difference in number of non-natives between suburban and central areas was quite small. In the city of Tampere, there are not continuous large areas devoid of vegetation. The number of native species remained high until the urban core and natives dominated in the rural-type areas of the city. However, there was not a great difference in the number of native species between rural and suburban areas. In the suburban areas, the detached houses and block-of-flats have little effect on the general vegetation. Proportionally, the share of natives decreases in line with the urban traits of the city. Urbanisation therefore affects native species in Finland. Overall, the characteristic features of a Finnish city, such as dispersed urban structure, small population, late urbanisation, abundant natural vegetation (forest) and the qualities of Finnish forests, guarantee the continuing diversity of urban vascular plants.     

“Mnandi-licious!” trends in African language usage in South African television advertising

Advertisements in African languages are generally confined to radio, and in that medium are factual, dialogic and direct. When used in television advertising, however, South Africa’s indigenous languages, particularly those spoken by the largest number of people in South Africa (Nguni languages), play a less informative role, being employed rather to index a concretised African essence, African identity or urban style, or a particular reified post-apartheid togetherness and cultural mobility. In this essay, we analyse four recent television advertisements, all using a Nguni language, and reflect on how and why the vernacular is used and to what extent African languages are no longer seen by television advertisers as carriers of information but as exploitable symbols of trustworthiness, multiculturalism, belonging and innovation. Key tropes that emerge as motivating the inclusion of African languages in television advertisements are identified and serve to organise and focus the argument.