Kerushka R. Pillay
Bio: Kerushka R. Pillay is an academic researcher from University of KwaZulu-Natal. The author has contributed to research in topics: Biodiversity & Home range. The author has an hindex of 2, co-authored 3 publications receiving 25 citations.
TL;DR: In this article, the authors investigated home range and habitat use of feral cats in an urban mosaic with varying degrees of urbanisation and green spaces in Pietermaritzburg, KwaZulu-Natal, South Africa.
Abstract: 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.
TL;DR: This paper reviewed case studies of vertebrate species' responses to urbanisation in KwaZulu-Natal, South Africa, to determine trends and presented a novel modification to the final of three phases of the framework described by Evans et al. (2010).
Abstract: Urbanisation is rapidly transforming natural landscapes with consequences for biodiversity. Little is documented on the response of African wildlife to urbanisation. We reviewed case studies of vertebrate species' responses to urbanisation in KwaZulu-Natal, South Africa to determine trends. Connected habitat mosaics of natural and anthropogenic green spaces are critical for urban wildlife persistence. We present a novel modification to the final of three phases of the framework described by Evans et al. (2010), which documents this sequence for vertebrate species persistence, based on the perspective of our research. Species in suburbia exhibit an initial phase where behavioural and ecological flexibility, life-history traits and phenotypic plasticity either contribute to their success, or they stay at low numbers. Where successful, the next phase is a rapid increase in populations and distribution; anthropogenic food resources and alternate breeding sites are effectively exploited. The modified third phase either continues to spread, plateau or decline.
TL;DR: Knowing and understanding of Cape porcupine food intake and dietary requirements give insight to their potential impact on commercial crops, which may aid in developing management and conservation strategies needed to manage this human—wildlife conflict.
Abstract: To better understand how Cape porcupines are able to successfully occupy many agricultural lands, we studied their digestive parameters and energy assimilation when fed three economically important agricultural crops (potatoes [Solanum tuberosum], sweet potatoes [Ipomoea batatas] and butternut [Juglans cinerea]). Daily food intake, daily gross energy intake, daily faecal energy loss, daily energy assimilated, daily water intake and apparent assimilation efficiency were calculated for each porcupine and for each diet trial. Cape porcupines maintained body mass on all three experimental diets and energy intake ranged from 3 002.36 kJ kg-1 d-1 (potato) to 4 499.00 kJ kg-1 d-1 (sweet potato). The moisture content in each experimental diet was relatively high (>60%) and preformed water intake of winter acclimated Cape porcupines ranged from 60 ml kg-1 d-1 (potato) to 100 ml kg-1 d-1 (sweet potato). Assimilation efficiencies were high (>85%) on all three diets. Cape porcupines ingested c. 1.5–2.7 kg of each cro...
TL;DR: In this paper, a typology of human responses to wildlife impacts, ranging from negative to positive, is proposed to help moderate the disproportionate focus on conflict between humans and wild animals.
Abstract: Humans have lived alongside and interacted with wild animals throughout evolutionary history. Even though wild animals can damage property, or injure humans and domesticated animals, not all interactions between humans and wildlife are negative. Yet, research has tended to focus disproportionately on negative interactions leading to negative outcomes, labelling this human–wildlife conflict. Studies have identified several factors, ranging from gender, religion, socio-economics and literacy, which influence people's responses to wildlife. We used the ISI Web of Knowledge database to assess quantitatively how human–wildlife interactions are framed in the scientific literature and to understand the hypotheses that have been invoked to explain these. We found that the predominant focus of research was on human–wildlife conflict (71%), with little coverage of coexistence (2%) or neutral interactions (8%). We suggest that such a framing is problematic as it can lead to biases in conservation planning by failing to consider the nuances of people's relationships with wildlife and the opportunities that exist for conservation. We propose a typology of human responses to wildlife impacts, ranging from negative to positive, to help moderate the disproportionate focus on conflict. We suggest that standardizing terminology and considering interactions beyond those that are negative can lead to a more nuanced understanding of human–wildlife relations and help promote greater coexistence between people and wildlife. We also list the various influential factors that are reported to shape human–wildlife interactions and, to generate further hypotheses and research, classify them into 55 proximate (correlates) and five ultimate (mechanisms) factors.
TL;DR: A.J.Gorman and R.G.Stone repelling moles, M.Lund progress in rodent control and strategies for the future, A.JG.Gosling and S.Neville as mentioned in this paper discussed the control of red and silka deer populations in commercial forests, P.R.Anderson et al.
Abstract: Mammals as pests, R.J.Putman the pest status of rodents in the UK, C.G.J.Richards ecological aspects of damage to sugar beet seeds by apodemus sylvaticus, H.J.Pelz Fossorial voles - problems and research, A.Meylan prevalence of pneumocystis Carinni and Leptospiraicterohaemorrhagiae in Danish rodents, J.Loda and M.Lund progress in rodent control and strategies for the future, A.B.Lazarus moles as pests, R.D.Stone repelling moles, M.L.Gorman and R.D.Stone the control of red and silka deer populations in commercial forests, P.R.Ratcliffe deer and habitat relations in managed forests, M.J.Hannan and J.Whelan impact of red and roe deer on Scottish woodlands, B.W.Staines and D.Welch demographic implications for the control of grey squirrels, J.Gurnell bark-stripping by grey squirrels in Britain and North America - why does the damage differ, R.E.Kenward demographic consequences of differences in ranging behaviour of male and female copyus, L.M.Gosling and S.J.Baker rabbits as pests in winter wheat, M.J.Crawley rabbit ranging behaviour and its implications for the management of rabbit populations, A.R.Hardy et al population dynamics of parasites of the wild rabbit, B.Boag badger damage - fact or fiction?, R.G.Symes badgers as pests in English vineyards, T.J.Roper et al the control of rabies in urban fox populations, G.C.Smith and S.Harris the mink menace? a reappraisal, N.Dunstone and M.Ireland economic damage by feral American mink in England and Wales, M.D.K.Harrision and R.G.Symes British seals - vermin or scapegoats?, S.S.Anderson et al feral cats - management of urban populations and pest problems in neutering, P.N.Neville.
TL;DR: It is suggested that porcupines can revert to the use of optimal food resources, when local selective forces allow it, when a high poaching pressure could be expected.
Abstract: Urban areas not only provide wildlife with new ecological niches, in terms of food availability, human protection and den sites but also they increase the possibility of conflict with man. Despite being a protected species in Italy, the crested porcupine is considered as an agricultural pest, with a tasty meat, thus widely poached. We studied food selection and other ecological factors shaping the ranging behaviour of crested porcupines in a suburban area, where a high poaching pressure could be expected. We monitored radio-tagged adult, paired crested porcupines throughout 1 year. Over 70% of individually marked porcupines were poached. Despite the local absence of predators, but in presence of poaching pressure, porcupines avoided clear moonlight nights and daylight activity, establishing dens in thorny thickets. Deciduous woodlands and shrubwood were positively selected for feeding throughout the year, while farmlands and fallows were underused. Although the crested porcupine has been confirmed as a “generalist” species in terms of food selection, with adaptations to dig underground storage organs, a strong preference for fruits and epigeal parts of plants was detected in our study. Porcupines evolved in Asia and Africa with a number of competing grazing herbivores, as well as in presence of a heavy predation risk leading to development of quills. This might have confined them to exploit roots and rhizomes as food, as well as scrub habitats for protection. Our results suggest that porcupines can revert to the use of optimal food resources, when local selective forces allow it.
01 Jan 2020
TL;DR: In this article, the authors reviewed the current knowledge of patterns, processes, impacts and management of invasions in South African urban ecosystems, and identified priorities for research, and key challenges for management.
Abstract: As in other parts of the world, urban ecosystems in South Africa have large numbers of alien species, many of which are invasive. Whereas invasions in South Africa’s natural systems are strongly structured by biotic and abiotic features of the region’s biomes, the imprint of these features is much less marked in urban ecosystems that exist as islands of human-dominated and highly modified habitat. Surprisingly little work has been done to document how invasive species spread in South African urban ecosystems, affect biodiversity, ecosystem services and human well-being, or to document the human perceptions of alien and invasive species, and the challenges associated with managing invasions in cities. This chapter reviews the current knowledge of patterns, processes, impacts and management of invasions in South African urban ecosystems. It highlights unique aspects of invasion dynamics in South African urban ecosystems, and identifies priorities for research, and key challenges for management. South African towns and cities share invasive species from all taxonomic groups with many cities around the world, showing that general features common to urban environments are key drivers of these invasions. There are, however, several unique biological invasions in some South African urban settings. The pattern of urbanisation in South Africa is also unique in that the imprint of Apartheid-era spatial planning is striking in almost all towns and cities and is aligned with stark disparities in wealth. This has resulted in a unique relationship between humans and the physical environment (e.g. very different assemblages of alien species in affluent compared to low-income areas). New ways of approaching invasive alien species management are emerging in South African towns and cities, but better facilitating mechanisms and protocols are needed for dealing with conflicts of interest.
TL;DR: In this paper, the impact of free-ranging domestic cats may seriously affect the conservation of threatened and non-threatened wildlife species, which already suffer from population declines due to habitat loss.
Abstract: Amongst domestic animals, cats Felis catus are widely considered as one of the most serious conservation threats for wildlife. This is particularly evident for island ecosystems, as data for the mainland are often lacking. In Italy, the European richest country in biodiversity, cats are very popular as pets. We collected data on impact by cats both through a citizen science approach (wildlife predations by 145 cats of 125 owners) and by following 21 of these 145 cats for one year and recording all the prey they brought home. Domestic cats killed at least 207 species (2042 predation events); among those, 34 were listed as “Threatened” or “Near Threatened” by the IUCN and Italian Red Lists. Birds and mammals such as passerines and rodents were most commonly reported to be killed by free-ranging cats. As to the diet in functional trait space, we observed that the class occupying the largest functional space was that of birds, followed by mammals, reptiles and amphibians. Thus, the largest impact was on the functional structure of mammal and bird communities. The use of a tinkerbell did not affect predation rate by cats, and numbers of prey items brought home decreased with increasing distance from the countryside. We provide evidence that the impact of free-ranging domestic cats may seriously affect the conservation of threatened and non-threatened wildlife species, which already suffer from population declines due to other causes, e.g. habitat loss. The mitigation of impacts by domestic cats on wildlife requires dissemination projects promoting responsible cat ownership, as well as restriction in free‐ranging behaviour, particularly in night time.