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.
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.
Restauración del bosque de Scalesia invadido por mora: Impactos en la vegetación, los invertebrados y las aves has been published in Informe Galápagos.
Authors Jäger H, S Buchholz, A Cimadom, S Tebbich, J Rodríguez, D Barrera, A Wolentowitz, M Breuer, A Carrión, C Sevilla & C Causton
Grasshopper diversity of urban wastelands is primarily boosted by habitat factors has been published in Insect Diversity and Conservation.
Authors Eckert S, Möller M & Buchholz S
Abstract Urban wastelands are considered to be valuable habitats for biodiversity conservation, but empirical evidence for several poorly investigated taxa such as grasshoppers is still pending – although urgently required for reasonable habitat management and urban planning. For the first time, we analysed grasshopper diversity of urban wastelands at different diversity levels, namely, alpha and functional diversity. In 2014, we selected 24 urban wastelands in the city of Berlin (Germany).
We analysed the relationships between local and landscape factors and different measurements of diversity (species richness, Simpson diversity, functional dispersion, functional evenness and functional divergence). We sampled 21 species, which represented about 45% of the entire grasshopper fauna of Berlin and numerous species of conservation interest were present at the investigated sites. Grasshopper diversity was best explained by local factors, with herb cover having a positive effect on alpha and functional diversity. Human impact and accessibility increased the conservation value of urban wasteland sites.
Late successional stages are very important for a high grasshopper diversity in general but early stages are mandatory to promote species of conservation concern. Urban wastelands can be turned into most promising transition zones for city-dwellers that fulfil the needs of conservationists and specialised species at the same time. To achieve this goal we recommend minimum requirements for successful habitat management.
Conference talk in Braunschweig
The German Society of general and applied Entomology (DGaaE) and the German Scientific Society for Plant Protection and Plant Health (DPG) organised a conference on insect diversity in cities (III. Urbane Pflanzen Conferenz). I contributed a talk on habitat function of urban meadows for wild bees with emphasis on urbanisation effects (see Abstract in German). Due to a very diverse audience with many relevant stakeholders and decision-makers (e.g. scientists, gardeners, landscape planners, landscape architects, authorities and NGOs) it was possible to elaborate this topic from different perspectives. At the end we had very interesting – sometimes controverse – discussions to develop recommendations how to make cities more insect friendly and to comment on the new white book „Grün in der Stadt“ which was recently send out for preview. The official presentation of the white book will be in May 2017.
Trait composition and functional diversity of spiders and carabids in linear landscape elements has been published in Agriculture, Ecosystems and Environment.
Authors Schirmel J, Thiele J, Entling MH & Buchholz S
Abstract Agricultural intensification is a cause of global biodiversity decline. Seminatural linear landscape elements (LLE) within agricultural landscapes can considerably mitigate these declines, but their effects on functional properties of biodiversity are poorly known. We analyzed trait composition and functional diversity (functional dispersion) of spiders and carabids in woody and herbaceous LLE. We expected that species assemblages of woody LLE are more diverse and K-selected compared to herbaceous LLE, and that effects of environmental parameters vary between LLE types. We selected 58 LLE in an agricultural landscape in Northwest Germany. We sampled carabids and spiders by pitfall trapping and measured landscape connectivity, landscape-wide land-use diversity, local land-use diversity, and local plant richness as explanatory variables. The trait composition of arthropods in woody LLE was more K-selected (lower dispersal ability, a higher food specialization or trophic level) than in herbaceous LLE. Moreover, spider functional diversity was higher in woody LLE. Spider functional diversity and proportion of predatory carabids in woody LLE increased with increasing connectivity of the habitats. In contrast, in herbaceous LLE local plant richness and landscape-wide land-use diversity were most important drivers for spider and carabid diversity and traits. Our results show that species richness and functional diversity of spiders and carabids were differently affected by landscape and local factors. Therefore, the importance of landscape connectivity was higher in woody LLE, suggesting that their inhabitants are more sensitive to habitat fragmentation than the highly mobile generalist species living in herbaceous habitats.