Sascha Buchholz

Urban ecology is a rapidly growing research field that has to keep pace with the pressing need to tackle the sustainability crisis. As an inherently multi‐disciplinary field with close ties to practitioners and administrators, research synthesis and knowledge transfer between those different stakeholders is crucial. Knowledge maps can enhance knowledge transfer and provide orientation to researchers as well as practitioners. A promising option for developing such knowledge maps is to create hypothesis networks, which structure existing hypotheses and aggregate them according to topics and research aims. Combining expert knowledge with information from the literature, we here identify 62 research hypotheses used in urban ecology and link them in such a network. Our network clusters hypotheses into four distinct themes: ( i ) Urban species traits & evolution, ( ii ) Urban biotic communities, ( iii ) Urban habitats and ( iv ) Urban ecosystems. We discuss the potentials and limitations of this approach. All information is openly provided as part of an extendable Wikidata project, and we invite researchers, practitioners and others interested in urban ecology to contribute additional hypotheses, as well as comment and add to the existing ones. The hypothesis network and Wikidata project form a first step towards a knowledge base for urban ecology, which can be expanded and curated to benefit both practitioners and researchers.

The insect crisis, as conservation topic, has historically received little attention among the general public. Yet, the publication “More than 75% decline over 27 years in total flying insect biomass in protected areas” by Hallmann et al. gained vast media coverage in Germany in October 2017. Given the media's known influence on public perception, we investigated (i) whether coverage of this publication increased awareness among the German public for insect die‐off, and (ii) whether it contributed to people's intentions to undertake insect protecting actions. We used Google Trends to examine people's internet activity in Germany in relation to keywords relevant to our research question. A high peak in Google searches for insect die‐off (“Insektensterben”) was indeed visible immediately after the study publication, and search volume remained significantly higher for the following 6 months, confirming that the topic gained attention. Further, searches for the three keywords insect hotel , bee‐friendly and bee meadow (“Insektenhotel”, “bienenfreundlich”, “Bienenweide”) increased significantly over the summers of the years 2017 to 2019. It appears that increased media attention around insect die‐off spurned by the publication of Hallmann et al not only addressed the crisis but also encouraged implementation of simple insect protection measures by the public. These findings suggest that cooperation between the media, conservation organizations and scientists to disseminate evidence‐based information alongside practical conservation measures may have lasting benefits. Read the free Plain Language Summary for this article on the Journal blog.