Urbanisation is increasing worldwide and is regarded a major driver of environmental change altering local species assemblages. Private domestic gardens contribute a significant share of total green area in cities, but their biodiversity has received relatively little attention. Previous studies mainly considered plants, flying invertebrates such as bees and butterflies, and birds. By using a multi-taxa approach focused on less mobile, ground-dwelling invertebrates, we examined the influence of local garden characteristics and landscape characteristics on species richness and abundance of gastropods, spiders, millipedes, woodlice, ants, ground beetles and rove beetles. We assume that most of the species of these groups are able to complete their entire life cycle within a single garden. We conducted field surveys in thirty-five domestic gardens along a rural-urban gradient in Basel, Switzerland. Considered together, the gardens examined harboured an impressive species richness, with a mean share of species of the corresponding groups known for Switzerland of 13.9%, ranging from 4.7% in ground beetles to 23.3% in woodlice. The overall high biodiversity is a result of complementary contributions of gardens harbouring distinct species assemblages. Indeed, at the garden level, species richness of different taxonomical groups were typically not inter-correlated. The exception was ant species richness, which was correlated with those of gastropods and spiders. Generalised linear models revealed that distance to the city centre is an important driver of species richness, abundance and composition of several groups, resulting in an altered species composition in gardens in the centre of the city. Local garden characteristics were important drivers of gastropod and ant species richness, and the abundance of spiders, millipedes and rove beetles. Our study shows that domestic gardens make a valuable contribution to regional biodiversity. Thus, domestic urban gardens constitute an important part of green infrastructure, which should be considered by urban planners.

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The Asp viper (Vipera aspis) is a highly endangered species in the Swiss Plateau and in the Jura Mountains of Switzerland. In the past, numerous populations disappeared due to human activities, but currently the trend is reversed and several locations seem favourable for this species. However, it is not known if the remaining populations are still genetically variable and viable. In this study, 12 new mierosatellite loci markers were developed for Vipera aspis using Next Generation Sequencing (NGS) techniques (454 sequencing). All markers proved to be polymorphic with 2-9 alíeles. When cross-tested with two Eurasian widespread viper species, 8 of the newly developed loci provided reliable amplification for V. berus and 3 loci for V. ammodytes.

Sex-biased dispersal is common among vertebrates and numerous studies have documented a tendency towards male-biased dispersal in mammals and female-biased dispersal in birds. A few studies have demonstrated that male-biased dispersal seems to be prevalent in reptiles. However, most of these studies considered only a single study site without taking into account possible local variability. We investigated sex-biased dispersal in Vipera aspis in four study sites in Switzerland using microsatellite markers and we predicted a higher dispersal in males than females. In two study sites, females were more spatially autocorrelated and showed a stronger isolation by distance compared with males, which suggests male-biased dispersal. In the other two study sites, the absence of sex-biased dispersal could have been the result of habitat fragmentation. Surprisingly, the dispersal ability of females was similar in the four sites, regardless of habitat fragmentation. This finding suggests a limited impact of habitat on female dispersal and the opposite for male dispersal. Our study demonstrates the importance of inferring sex-biased dispersal in different habitats, because local barriers can affect the outcome of such studies. Hence, general conclusions about patterns of sex-biased dispersal should be drawn with caution when studies are conducted at a single study site.

Urban gardens are important for human well-being, biodiversity and other ecosystem functions. Biodiversity-promoting initiatives would benefit from their owners being aware of the state of biodiversity in their gardens. We examined whether garden owners’ perceptions match actual biodiversity in their gardens and whether perceptions are influenced by the owners’ ecological knowledge. We used a structured interview to assess the motivations and biodiversity knowledge of owners of 33 domestic gardens in the city of Basel (Switzerland) and related them to a survey of native plants and several groups of ground-dwelling invertebrates in their gardens. Owners showed different priorities, with promotion of habitat for biodiversity, receiving, on average, higher scores than cultivation, recreation and garden designing. Owners prioritizing biodiversity promotion had gardens with high habitat richness. The garden owners’ perceptions of both native plant and overall invertebrate diversity were not correlated with actual diversity data for native plants and ground-dwelling invertebrates. The perceptions of the abundance of invertebrate groups by garden owners with good biodiversity knowledge were not more accurate than those from owners with less knowledge. Despite their willingness, many owners do not know all the opportunities to promote biodiversity. Initiatives to further biodiversity-friendly gardening should thus transfer knowledge.