The impact of natural and artificial light at night on the flight behaviour of moths

• Applicant: Dr. Jacqueline Degen
• Subject Area: Sensory and Behavioural Biology
• Term: since 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 388224099

The invention of electric light massively changed the light environment that nocturnal insects are adapted to. Recording of flight trajectories over several hundred meters using harmonic radar revealed, that orientation of moths is significantly affected by streetlights, although only a small fraction of individuals finally flies towards the light source. The impact of light pollution on insect orientation, therefore, has been severely underestimated to date. Moreover, experiments revealed that the rising moon promotes mate finding in moths, but to date behavioural data in pristine landscapes are lacking. Using field and laboratory experiments, the present project particularly aims at understanding the circumstances eliciting attraction. A major focus is dedicated to unveiling the interplay between streetlight height and intensity on attraction, the impact of streetlights in pristine landscapes, and weighting of natural and artificial light cues in a conflicting situation. The expected findings will not only be relevant for a deeper understanding of insect orientation but will also provide a basis for understanding why moths fly towards the light. Moreover, they have high relevance for nature conservancy and pest control and can contribute to advance insect friendly lighting. Besides, recently developed technologies for performing location-independent 3D tracking of free flying moths accompanied by quantitative and qualitative 360° light measurements in different altitudes shall be established. Together, they represent major developments in the research field of light pollution.

• DFG Programme: Research Grants