INSECT BEHAVIOUR & SYMBIOSIS

The overall aim of this research group is to apply ecological and evolutionary concepts to forest insect and their biotic environment. The goal is to develop concepts how to protect the ecological and economical services of native forest ecosystems, which are currently threatened by ongoing climate change and a loss of biodiversity.

Our research is characterized by the integration of different disciplines, such as evolutionary biology, ecology, behavioral biology, microbiology, molecular biology and chemical ecology. This transdisciplinary approach allows us to understand the life of forest insects in their ecological relationships with other animals, plants, and microorganisms, and to make statements about the role of these relationships on forest insect population dynamics. Our main model system are wood-boring beetles, in particular bark beetles, and their associations with bacterial and fungal symbionts. We explore these multipartite symbioses in all their microbiological, molecular and chemical details to get an overarching understanding how these different organisms influence each other and either facilitate or hamper their insect hosts in colonizing trees.

One of our most important achievements was the establishment of a laboratory breeding system for various bark beetles, which allows now the consecutive rearing and the experimental manipulation of beetle nests, which are normally inaccessible and hidden below the bark or inside the wood. Using this technique, we are globally visible for our approach to study these insects at different scales from inside their nests in the laboratory to their population dynamics in the field. Along these lines our core fields of research are: (1) the study of the influence of macro- and microorganisms on forest-relevant insects in the field, (2) the experimental laboratory manipulation of relationships between these organisms and their physiological and ecological consequences, (3) the microscopic-histological study of the transmission of microorganisms (especially symbionts) by insects, and (4) the chemical ecology and molecular genetic basis of insect-microorganism interactions.

At our institute we have all the rearing facilities, microscopical, entomological, microbiological and molecular biological labs and are thus excellently equipped to tackle the above-mentioned research questions. Located next to our own experimental forest, with greenhouses and flying and rearing cages for bark beetles, there is probably no better place to study forest insects both in the laboratory and in the field.

Current projects

FOREST PROTECTION

Forest protection and pest management are crucial for successful and sustainable forestry. Research in these fields is multi-dimensional and covers biology, ecology, chemo-ecology, forest management, and more. Forest practitioners demand for fast and economic solutions, nature conservation for low impact, and science wants to understand insect communication or the ecological processes behind the observations whilst outbreaks.

Our research is driven by both, understanding the basics of behavior, communication, dynamics, etc. of insects and providing applied knowledge. Therefore, we do mainly field studies (regularly together with collaborators from forestry) and supplement those with lab studies and experiments under semi-natural conditions in the vicinity of the institute.

Our self-conception is to involve students in research on as many levels as possible and thus to live the fusion of research and teaching.

Currently we are mainly working on bark beetles on spruce and fir to improve insecticide-free management measures to control populations and on early-detection, as effective monitoring is fundamental for any population management.

Current Projects

HOST-MICROBIOME INTERACTIONS

Microbes are everywhere and there is literally no organism that does not interact with them in at least some way. These interactions can be highly diverse ranging from pathogenic to mutualistic. Specifically, host-associated symbionts (microbiome) have been shown to affect diverse biological host traits such as nutrition, development, immunity and even behavior and can be therefore key drivers of organism’s ecology and evolution.

Bark beetles are one of the most species-rich herbivorous insect groups with high diversity in ecology and host-plant usage. While the importance of their symbiosis with specific fungi for succeeding their life cycles is acknowledged, the knowledge about the role of the diverse bacteria and other fungi (such as yeasts and molds) in the different bark beetle systems is still in its larval shoes. This is offering a ton of possibilities to explore, considering specifically microbial interactions with the beetle, the symbiotic fungi as well as the tree environment.

Some research foci are:

  • Understanding the role of symbionts during beetle development
  • Microbiome and sociality
  • Microbiome evolution

Current Projects

BIODIVERSITY – “GREEN WITTENTAL”

East of Freiburg, on the edge of the Dreisamtal, the domicile of the Professorship of Forest Entomology and Forest Conservation is located on an approx. 1.5 ha site with large open areas, its own forest stand, greenhouses and laboratories. The laboratory equipment as well as the different habitats offer optimal working conditions for entomological-ecological studies. It already shows a high conservation value and has a great potential for development.

Against the background of the current biodiversity crisis (keywords „insects “and „bird decline“) but also the lack of practical offers for teaching species knowledge in the education at the Faculty of Environment and Natural Resources, we would like to sustainably promote biodiversity at this unique location (restoration of habitats and improvement of their quality through a targeted insect-friendly management) and in the future use it even more in university teaching and create a freely accessible place for students to learn and practice outside of courses.

Through relatively simple measures (modified mowing regimes of flowering meadows, ponds, stone walls, dead wood, nesting aids, etc.), valuable biotopes for animals and plants that have become rare are created together with students, which are to be used simultaneously for teaching (modules, qualifying papers), research, but also general education regarding biodiversity and nature conservation.

With this initiative, we hope to create momentum at the university to create more such natural areas to promote animal and plant diversity on university lands. These plots can be used in the future both to improve the taxonomic education of our students and to raise awareness among a broader public about the value of biodiversity, the current biodiversity crisis, and possible measures of improvement.

Selection of projects conducted:

  • Inventory of flora and fauna on the premises of the Professorship of Forest Entomology and Forest Protection
  • An inventory of Carabidae and other ground-dwelling arthropods
  • Inventory and swarming behavior of xylobiont coleoptera in the institute forest
  • The Malaise trap as a method for catching nocturnal flying insects
  • Wild bees – monitoring
  • Do managed bees have effects on the abundance and species richness of wild bees?
  • Assessing the relationship between habitat characteristics and insect communities using the entomological umbrella method

Current Projects