INSECT – A Research Initiative on the Changes in the Insect Fauna of Switzerland
What is the state of insects in Switzerland? What changes have there been, and what has caused them? Researchers study these questions in the project ‘INSECT’.
Studies on changes in insect communities in recent decades in relation to potential drivers such as global warming or land-use change are rare. For this reason, Agroscope and its partner organisations WSL, FiBL, info fauna and the Swiss Ornithological Institute have launched the project ‘INSECT’.
Database of insect records
The organisation ‘info fauna’ curates a database of species records for insects and other fauna for Switzerland. In the project ‘INSECT’, these records are statistically analysed with occupancy-detection models. In a first analysis, 1.5 million records from naturalists and professional researchers on three common insect groups are used. Changes in the distribution of 215 butterfly, 103 grasshopper and 72 dragon- and damselfly species covering different traits are estimated for a 40-year period (1980–2020) for different regions of Switzerland as well as for different elevations. At the same time, data on climate change (e.g. mean temperature, summer drought) and on large-scale changes in land use (e.g. utilised agricultural area, intensity of grassland use) over the same time period are compiled.
Catches from pitfall traps
In addition, Agroscope and its partner organisations use data on insects and spiders from pitfall traps, covering the past 45 years. Based on 1.73 million recorded individuals, trends in the frequency, diversity and biomass of insects and spiders are reconstructed for various habitats. These are then correlated with small-scale changes, e.g. in land use.
Resampling of former study areas
Former study areas from different projects of Agroscope and partner organisations will be resampled in the coming years. At the same time, detailed land-use data are being collected to identify small-scale changes. With this, local factors that can prevent negative insect population trends or contribute to positive population trends will be determined.
The goal: recommendations for the protection of insect diversity
Agroscope is planning to resample agricultural sites in three case-study regions.