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The South African National Biodiversity Institute's SABIF (South African Biodiversity Information Facility) digitization program and the National Research Foundation of South Africa.

Globally, as trends of urbanisation continue to intensify, there has been increasing concern over the impacts of urban expansion on biodiversity and greater attention towards addressing these impacts. Ecological infrastructure such as urban rivers and their catchments may enhance biodiversity, ecological functioning and ecosystem service delivery within cities. Birds are good indicators of urban habitat quality because their ecology is well-studied and they are habitat selective. This study assesses the ecological value of a small urban river catchment in Cape Town, South Africa, in terms of its effect on the taxonomic and functional diversity of birds. 178 bird counts were carried out at 89 sites and 95 species were recorded. The nine functional groups considered were present in equal proportions in the catchment and in the whole of southern Africa, making the catchment a microcosm of the region’s avifauna in terms of functional composition. Using RLQ and fourth-corner analyses, we showed that the river was responsible for the occurrence of certain species and functional groups that would not otherwise occur in the suburbs. Nutrient movers, insectivores, scavengers and seed dispersers responded strongly to a gradient of distance from the river and the position on the river. Contrary to the homogenised assemblage that might be expected of an urban area, the catchment contains a taxonomically and functionally diverse bird assemblage. The combination of a river, a heterogeneous urban matrix and an adjacent national park makes this catchment an exemplar of the value of ecological infrastructure for urban biodiversity.

In natural populations, virus circulation is influenced by host behavior and physiological characteristics. Cat populations exhibit a great variability in social and spatial structure, the existence of different ways of life within a same population may also result in different epidemiological patterns. To test this hypothesis, we used a logistic regression to analyze the risk factors of Feline immunodeficiency virus (FIV), feline herpes virus (FHV), feline calicivirus (FCV), and feline parvovirus (FPV) infection in owned (fed and sheltered) and unowned (neither fed nor sheltered, unsocialized) cats living in a rural environment in the North Eastern part of France. A serological survey was carried out in 492 non-vaccinated and non-sterilized individuals from 15 populations living in the same area. The prevalence of feline leukemia virus (FeLV) was also studied, but too few were infected to analyze the risk factors of this virus. For each virus, the epidemiological pattern was different in owned and unowned cats. Unowned cats were more frequently infected by directly transmitted viruses like FIV, FHV and FCV (21.22%, 67.66%, 86.52% in unowned cats vs 9.55%, 53.88%, 77.18% in owned cats, respectively), a difference that may be explained by a more solitary and more aggressive behavior in unowned adults, and/or possibly by a higher sensitivity related to a more stressful life. On the contrary, owned cats were more frequently infected with FPV (36.41% in owned cats vs 15.61% in unowned cats), possibly as a result of their concentration around human settlements. The present study showed that owned and unowned cats living in a same area have behavioral and physiological characteristics sufficiently different to influence virus circulation. Pooling different types of cats in a single sample without taking it into account could give a wrong picture of the epidemiology of their viruses. The conclusion of this work can be extended to any epidemiological studies led in wildlife species with flexible behavior as any variations in social or spatial structure, between or within populations, could result in different virus circulation.