Policy buzz

Policy buzz

This week European Commission announced the new EU Pollinator Initiative, the updated and strengthened version of Communication first published in 2018.

The new Initiative identifies actions organized under three overarching priorities: 1. improving knowledge of pollinator decline, its causes, and consequences; 2. improving pollinator conservation and tackling the causes of their decline: and 3. mobilizing society and promoting cooperation and strategic planning.

Activities include finalizing action plans for threatened pollinator species, identification of pollinators typical of habitats protected under the Habitats Directive, mapping of Key Pollinator Areas, devising a blueprint for a network of ecological corridors for pollinators (so-called Buzz Lines), and much more – the total of 42 pollinator actions.

The revised Initiative also addresses climate change as one of the drivers of pollinator decline and sets out to identify the most climate-vulnerable zones for pollinators and devise and implement climate adaptation measures.

The initiative will also – together with other new EU legislation, such as the proposal for Regulation on nature restoration – address causes of extinction (such as chemical pesticides and habitat loss) and establish EU pollinator monitoring. The monitoring program will entail the annual collection of standard data on wild pollinators across the entire European Union, allowing us to measure the success of this initiative, and of our efforts to restore and protect wild pollinators.

Illustration: EU Pollinator Information Hive

Hoverfly taxonomy course

Hoverfly taxonomy course

We spent the last week in Novi Sad, attending the advanced hoverfly identification course, organized within the European project SPRING. The organizers of this course are a group of over 10 hoverfly researchers from the Department of Biology and Ecology of the University of Novi Sad. Long term, these courses aim to increase the number of hoverfly experts in Europe, which is critical for the successful establishment of EU Pollinator Monitoring.

One of the main goals of this course was learning the taxonomically “difficult” genera, where species identification is not exactly trivial. Throughout the week, we learned about these complex, but interesting, and beautiful genera, such as Cheilosia, Chrysotoxum, Eumerus, Merodon, Paragus, Platycheirus … – in which different species often look remarkably similar. Nevertheless, everything seemed possible under the expert guidance of our enthusiastic teachers and in the good company of other students, about 10 pollinator lovers from across Europe.

During the week, in addition to the course, our instructors found time to help us with Cro Buzz Klima hoverfly samples and teach us some new lab skills important for species identification. In addition to all that work, our hosts and fellow attendees were also excellent company. But what impressed us the most was the enthusiasm and love our hosts have for these important and beautiful insects, which they successfully passed on to us and which will motivate us to continue our work for a long time to come.

Pollinators on the edge: The European Red List of Hoverflies

Pollinators on the edge: The European Red List of Hoverflies

The European Red List of Hoverflies, which provides conservation status for European hoverfly species, was published last week. Hoverflies, the family Syrphidae, are abundant, diverse, and surprisingly handsome flies. Many species are bee or wasp mimics. Hoverflies are also the second most important group of pollinators, right after bees. Being second to bees doesn’t mean we could live without them – hoverflies visit a different spectrum of flowers, fly longer distances, and thrive in different climates and habitats than bees, all of which make them irreplaceable.

In the published Red List, 55 scientists and experts estimate that as many as 314 hoverfly species (about 37%) are threatened with extinction in Europe, and an additional 61 species (about 7%) are near threatened. Only slightly above half of all species are considered of least concern (469 species, 52.7%). About 5% of species are data deficient (DD), meaning we lack the data for assessing them.

For hoverfly conservation, it is important to consider the diverse life strategies of hoverfly species, whose larvae live in a wide range of habitats and have varied diets. Adult hoverflies feed on nectar and pollen, but their larvae can be aphid predators, feed on dead organic matter in wet habitats, eat plants, be associated with old trees, or live in an ant nest. One of the reasons why hoverflies are endangered could be the loss of larvae habitats, especially of old trees and wet habitats.

This assessment also answers the “Now what?” question, what to do with this long list of endangered species? In the accompanying document, authors propose grouping endangered species by their natural history and planning specific population recovery activities for each group. The emphasis is on the conservation of old, veteran trees through changes in forest management, protection and restoration of wet habitats, and promotion of sustainable agriculture – activities that will help many other groups of organisms and the environment.

In addition, hoverflies also still need a good amount of PR, as they are not as well-known and popular as bees or butterflies. If you want to learn more about these beautiful and important flies, we recommend the IUCN Hoverfly Specialist Group. And tell one person today – Have you heard about hoverflies?


Vujić, A., Gilbert, F., Flinn, G., Englefield, E., Ferreira, C.C., Varga, Z., Eggert, F., Woolcock, S., Böhm, M., Mergy, R., Ssymank, A., van Steenis, W., Aracil, A., Földesi, R., Grković, A., Mazanek, L, Nedeljković, Z., Pennards, G.W.A., Pérez, C., Radenković, S., Ricarte, A., Rojo, S., Ståhls, G., van der Ent, L.-J., van Steenis, J., Barkalov, A., Campoy, A., Janković, M., Likov, L., Lillo, I., Mengual, X., Milić, D., Miličić, M., Nielsen, T., Popov, G., Romig, T., Šebić, A., Speight, M., Tot, T., van Eck, A., Veselić, S., Andric, A., Bowles, P., De Groot, M., Marcos-García, M.A., Hadrava, J., Lair, X. , Malidžan, S., Nève, G., Obreht Vidakovic, D., Popov, S., Smit, J.T., Van De Meutter, F., Veličković, N. and Vrba J. (2022). Pollinators on the edge: our European hoverflies. The European Red List of Hoverflies. Brussels, Belgium: European Commission.

Sculptured resin bee

Sculptured resin bee

A new study is published about alien bee species that is spreading across Europe

The sculptured resin bee, Megachile sculpturalis, is a potentially invasive alien pollinator in Europe. Native in East Asia. it was unintentionally introduced to North America in the nineties, and France in 2008, from where it rapidly spread across Europe. It has been present in Croatia since 2018.

The sculptured resin bee is a solitary species. Females nest in existing cavities and cracks in dead wood, similar to our native carpenter bees (genus Xylocopa). They collect plant resins to seal their nests, which is how they got their common name. They are active in the summer and collect pollen and nectar from various plant species. In Europe, they are mostly found on non-native ornamentals, such as the Japanese pagoda tree (Styphnolobium japonica) and Chinese wisteria (Wisteria sinensis). The sculptured resin bee is easy to recognize – large (larger than a honeybee), with a black head and abdomen, a light brown, hairy thorax, and opaque wings.

We still don’t have enough data to know if this species has a negative impact on our native pollinators. However, there is some evidence of competition for nesting resources and aggressive behavior, so we consider it potentially invasive. That is why it is important to continue research and monitoring.

The newly published research, in which we had a chance to participate, reports the spread of the sculptured resin bee across Southeast Europe and new data about the species’ ecology. In addition to field research by an international team of scientists, this work also involved citizen scientists. The sculptured resin bee is easy to recognize, favors populated places, and is not dangerous for humans. All of this makes it a good candidate for citizen science – a practice in which citizens collect data used for scientific research.

Interestingly, in this study, the data collected by citizen scientists covered a five times bigger geographical area than the targeted research of scientists, which highlights the advantages of this approach for monitoring. We emphasize the benefits of collaboration of citizens and formal scientists and the importance of international collaboration for monitoring. You can read the published work here.

Want to get involved? If you see the sculptured resin bee, let us know! Report your observation through the app Invasive Species in Croatia or through the contact form on this website. The report should include the location and date of observation, and a photo or video of the species. Your data will contribute to the monitoring of the sculptured resin bee in Europe and to our understanding of its impact on our native ecosystems.

Photos: J. Bila Dubaić

Pollinator city

Pollinator city

One of the ways we can help wild pollinators is by changing the mowing regime of urban green spaces

We like it when nature is tidy. Shortly cut, monotonous lawns, parks that look like football or golf courses instead of flowering meadows, became the standard in city parks. What we like to call an urban green oasis is, from a biodiversity standpoint, a green desert.

Cities are, in the first place, spaces where a majority of the human population lives, and their primary function is not to maintain biodiversity. City parks also have an important socio-cultural role. However, with increasing urbanization and numerous environmental pressures, such as pollution and climate change, it is becoming clear that the greening of cities is essential for a sustainable future and human health. Green cities are also becoming a clearly defined goal of global and European policies.

Wild pollinators are particularly interesting in this regard. Studies have shown that cities can support diverse wild pollinator populations. Pollinator diversity is sometimes, unexpectedly, higher in cities than in surrounding areas, especially if those areas are affected by agriculture. This is especially true for bees, but with careful management of urban parks, we can improve habitats for other groups of pollinating insects as well, such as hoverflies, butterflies, and moths. Cities can indeed become green oases, but they need minor changes in the way they manage their green spaces: primarily reducing the use of chemical pesticides and changes in the mowing regime.

The standard of a neat lawn is achieved by frequent, intensive mowing, which is scientifically proven awful for the environment. Frequent mowing warms and dries the soil, reduces the diversity and biomass of plants and animals, and prevents the flowering of plants that are an important source of pollen and nectar for pollinators. The moment the lawnmower passes through the park, pollinators, and many other animals are suddenly left without food and shelter. Research in European and American cities shows that a reduced mowing regime is environmentally and economically beneficial – leading to increased diversity of animal and plant species, reduced greenhouse gas emissions, and financial savings of as much as 36%.

For all of those reasons, we decided to test pollinator-friendly management practices in the city of Zagreb. Our collaborators for these activities are Public Institution Maksimir for the management of protected areas of the city of Zagreb, Zrinjevac Subsidiary, and Croatian Museum of Natural History, and we have the support from the City of Zagreb and the City institute for cultural and natural heritage conservation. We defined test plots in three city parks: Maksimir, Ribnjak, and Rokov perivoj. In those parks we will establish the so-called short-flowering meadow – an area mowed only 4 times a year, and a long-flowering meadow – a strip along the edge of the lawn or a larger area mowed only once a year. This is an example of a mosaic mowing regime – although all surfaces are cut, not all are cut at the same time, so at least part of the area is in bloom at all times.

This mowing regime is based on similar actions from All-Ireland Pollinator Plan, which we have adapted to our conditions. This Plan has been a huge success in Ireland, where its implementation started in 2015. For example, one of the unexpected results was an increase in the number of rare orchids, which began to flower on roadsides just a year after the reduction of the mowing regime. Ireland is a great example, but good stories can be found in other cities as well, such as the urban meadows in Berlin, the Olympic Park in London, and beyond.

In Zagreb, for a start, we expect to see more dandelions, clover, and daisies in bloom, all fantastic native plants and a good source of food for pollinators. Pilot plots are also our Cro Buzz Klima project areas, and we will continue to monitor the abundance and diversity of plants, bees, hoverflies, and butterflies, which we partially started last year. This will allow us to assess how these changes are affecting urban biodiversity and how to plan the management of the green spaces of our cities in the future.

tabla Maksimir

P.S. If you belong to the part of the population that is wary of any bugs (useful to humans or not) and you are a little scared of all this, keep in mind that the increase in insect diversity (= larger number of different species) prevents pest outbreaks (= sudden increase in abundance of one species). Greater diversity means more natural enemies and a shift towards ecological balance. It also positively impacts the populations of other, larger predators (such as swallows, blackbirds, and other birds that feed on insects).