Long-term trends in insect populations and bringing together nationwide Malaise trap activities (TrendInsects)
| Federal State | Nationwide |
|---|---|
| Duration | 01.10.2026 - 30.09.2029 |
| Funding budget | 279,443 euros |
| Funding reference number | 3526600400 |
| Grant recipient | Senckenberg Society for Nature Research (SGN) |
| Project partners | Protected Area Administrations: DFG Biodiversity Exploratories Hainich-Dün and Swabian Alb, Bliesgau Biosphere Reserve (BR); Schaalsee-Elbe BR, Oberlausitzer Heide- und Teichlandschaft BR, Hessian Rhön BR, Black Forest BR, Flusslandschaft Elbe BR, Berchtesgaden National Park (NP), Eifel NP, Harz NP, Hunsrück-Hochwald NP, Jasmund NP, Kellerwald-Edersee NP, Niedersächsisches Wattenmeer NP, Black Forest NP, Unteres Odertal NP, Vorpommersche Boddenlandschaft NP, Natureum Niederelbe
Others: NLWKN (Lower Saxony State Agency for Water Management, Coastal Protection, and Nature Conservation), IfBI (Institute for Biodiversity Information e. V., Ebern), LBV Bavaria Institution for DNA metabarcoding: University of Duisburg-Essen (Research group of Florian Leese) |
| Funding by | National Monitoring Centre for Biodiversity (Federal Agency for Nature Conservation) |
Description
Background
Insects are central components of our ecosystems – as pollinators, decomposers, and a food source for many other animals. At the same time, there is still insufficient knowledge about how the diversity and composition of insect communities in Germany are changing over the long term. Although there are numerous indications of declines, reliable conclusions about trends over time require continuously collected and methodologically comparable data.
An important foundation for this is provided by the German Malaise Trap Program (GMTP), established in 2019 by the Long-Term Ecosystem Research Network Germany (LTER-D) and the National Natural Landscapes (NNL). Insects are collected annually using Malaise traps at 84 sites across 13 federal states. These samples are suitable for DNA metabarcoding. Using this methodology, the species identification was performed in samples from 2019 and 2020. This process revealed 31,844 unique insect species, 10,803 of which have an existing taxonomic identity in DNA barcoding databases, which impressively illustrates the vast amount of information that can be obtained using genetic information for species identification.
There are various projects in Germany that use Malaise traps. There is significant potential in closer collaboration and the consolidation of data from these programs. However, there are some challenges in this regard. The various Malaise trap and DNA metabarcoding programs differ in some respects in their methodology, and no uniform standards have been established yet. Furthermore, there is no systematic overview of what conclusions can be drawn from the respective sample sets. This is where the project TrendInsects comes in.
Objectives
The aim of the project is to establish the scientific and methodological foundations for improving the integration and comparability of data generated through the combination of Malaise traps and DNA metabarcoding. This will enable more reliable detection of long-term changes in insect diversity and make the resulting findings accessible and useful for biodiversity monitoring research and practice, as well as nature conservation.
Specific objectives
The project pursues four interrelated objectives:
Based on GMTP data, trends in insect biomass as well as in species and species group counts will be examined.
Existing DNA metabarcoding methods will be systematically evaluated, and recommendations for more consistent application and improved comparability will be developed.
Various projects using Malaise traps in Germany will be compared to identify opportunities for joint analysis and better intercalibration of the data.
Existing GMTP sites will be assessed to determine how well they represent Germany’s insect diversity - particularly in rare habitats and those of high conservation value.
Measures
To analyze long-term trends, existing GMTP data will be supplemented with new biomass and DNA metabarcoding data and consolidated into a unified dataset covering the period from 2019 to 2028. This will allow for the examination of changes in insect biomass as well as in species richness, while taking into account potential influencing factors such as land use, weather, climate, and protected area status.
At the same time, different DNA metabarcoding methods will be systematically compared. The project will examine how methodological differences affect the results and how comparability between studies can be improved. This will lead to recommendations for a more standardized application.
In addition, existing Malaise trap monitoring programs in Germany will be examined with regard to their methods, data structures, and opportunities for collaboration. Another focus is the analysis of the 84 GMTP sites. Their spatial distribution and associated habitats are being evaluated to identify strengths and potential gaps in the existing monitoring system.