Female moths call in vain: Streetlights diminish the promise of mating

Artificial light at night has increased strongly in recent decades and is
now affecting moths, a key contributor to pollination networks. The global
shift to light-emitting diode (LED) streetlights changes the nocturnal
light environment even further, especially because of their high
variability in spectrum and intensity. To date, the impact on mating
success of moths is only little  known, making it essential to
investigate their behavioural responses. We recorded the flight behaviour
of male moths (Sphinx ligustri) using a symmetrical flight tunnel. Two
different light environments with a female positioned on one side of the
tunnel were used to test the effect of different LEDs (1800K Amber, 2200K
Warm white, 3900K Neutral white) and intensities (0.05 lux, 150 lux, 370
lux, 590 lux) on arrival location, flight duration, and direction changes
of males. We have created two different light habitats within the tunnel.
A homogeneous light environment, with equal light on both sides of the
tunnel, and a heterogeneous light environment, with light only on one
side. In both habitats, the flight behavior of male moths was tested in
the presence of females. To test whether mating behavior was impaired, a
female was placed on only one side of the tunnel. In the heterogeneous
habitat, the opposite side of the light was used to create a conflict.