In this paper, we summarize the published literature in the growing field of wild bee functional ecology and review which functional trait-based analyses have been carried out on wild bees in cities thus far, summarize which wild bee species traits have been considered and evaluate any consistent wild bee trait–environment relationships across studies.
Recently, two articles were published in the journal ‚Sustainability‘. Both are open access and can be downloaded from the publications page.
New articles „CityScapeLab Berlin: a research platform for untangling urbanization effects on biodiversity“ „Clean, green urban wetlands benefit nocturnal flying insects and associated insectivorous bat predators“
„Wild bees in urban grasslands: Urbanisation, functional diversity and species traits“ has been published in Landscape and Urban Planning. We found that urbanisation was not related to neither taxonomic nor functional diversity in bee communities of urban grasslands. However, endangered bee species responded negatively to the isolation of grasslands but positively to flower coverage. Urbanisation, previous restoration efforts and site type filtered the functional composition of bee communities in terms of species traits related to diet and nesting. Our results substantiate the role of urban habitats for functionally diverse bee communities, including rare and endangered species, and indicate pathways towards enhancing habitat functions of urban grasslands for wild bees by improving the connectivity of urban grassland patches within the urban matrix, and more locally by adjusting management to maintain flower coverage in grasslands.
„Emerging Urban Forests: Opportunities for Promoting the Wild Side of the Urban Green Infrastructure“ has been published in Sustainability (free access). In this article we address opportunities associated with “emerging urban forests” such as spontaneously developing forests in cities for urban biodiversity conservation applying a multi-taxon approach.
We are launching a new research project to analyse wild boar effects on habitats, plant and insect biodiversity and sand lizard populations. This project is funded by Stiftung Naturschutz Berlin and will start in September 2019.
Implementing the Berlin Bee Strategy for conservation of bees and other pollinators in Berlin by optimising the protection of wild bees (funded bei Senatsverwaltung für Umwelt, Verkehr und Klimaschutz Berlin) – more info coming soon.
„Urbanisation modulates plant-pollinator interactions in invasive vs. native plant species“ has been published in Scientific Reports. The article is open access.
In this article, we show that invasive black locust (Robinia pseudoacacia) is a “pollinator-friendly” tree and attracts not only honey bees but also wild bees and other wild pollinators. However, we also found that attractiveness of black locust decreases with increasing urbanisation.
Tree cover mediates the effect of ALAN on urban bats has been published in Frontiers in Ecology and Evolution. For Download, please go to the Frontiers Webpage.
Abstract: With urban areas growing worldwide, so does artificial light at night (ALAN) which negatively affects many nocturnal animals, including bats. The response of bats to ALAN ranges from some opportunistic species taking advantage of insect aggregations around street lamps, particularly those emitting ultraviolet (UV) light, to others avoiding lit areas at all. Tree cover has been suggested to mitigate the negative effects of ALAN on bats by shielding areas against light scatter. Here, we investigated the effect of tree cover on the relationship between ALAN and bats in Berlin, Germany. In particular, we asked if this interaction varies with the UV light spectrum of street lamps and also across urban bat species. We expected trees next to street lamps to block ALAN, making the adjacent habitat more suitable for all species, irrespective of the wavelength spectrum of the light source. Additionally, we expected UV emitting lights next to trees to attract insects and thus, opportunistic bats. In summer 2017, we recorded bat activity at 22 green open spaces in Berlin using automated ultrasonic detectors. We analyzed bat activity patterns and landscape variables (number of street lamps with and without UV light emission, an estimate of light pollution, and tree cover density around each recording site within different spatial scales) using generalized linear mixed-effects models with a negative binomial distribution. We found a species-specific response of bats to street lamps with and without UV light, providing a more detailed picture of ALAN impacts than simply total light radiance. Moreover, we found that dense tree cover dampened the negative effect of street lamps without UV for open-space foraging bats of the genera Nyctalus, Eptesicus, and Vespertilio, yet it amplified the already existing negative or positive effect of street lamps with or without UV on Pipistrellus pipistrellus, P. pygmaeus, and Myotis spp. Our study underpins the importance of minimizing artificial light at night close to vegetation, particularly for bats adapted to spatial complexity in the environment (i.e., clutter-adapted species), and to increase dense vegetation in urban landscape to provide, besides roosting opportunities, protection against ALAN for open-space foraging bats in city landscapes.
Working at the Charles Darwin Research Station again
Thanks to a research fellowship sponsored by the Schimper Stiftung I was able to go to the Galápagos in February. It was great to continue my work on the Scalesia restoration project in the highlands of Santa Cruz. After intensive work in the invertebrate lab we finished all spider and beetles identifications and counted all other invertebrates caught within the long-term monitoring. This program started in 2014 and invertebrates were caught in 34 plots using pitfall and Malaise traps. First results have been recently published but more detailed analyses will be available soon.
Scalesia pedunculata – an endemic tree in the Galápagos
Argiope spec. – a spider species commonly found in Scalesia trees
Connectivity or area – what drives plant species richness in habitat corridors? has been accepted in Landscape Ecology.
Authors Thiele J, Kellner S, Buchholz S & Schirmel J
In a nutshell, we found out that connectivity is more important for plant species richness in linear landscape elements than area. In particular, the richness of plant species that are dispersal limited and confined to semi-natural habitats benefits from connective networks of linear landscape elements in agricultural landscapes.