Artificial light at night also makes guppies more courageous during the day, according to a behavioural study led by researchers from IGB and the Max Planck Institute for Human Development. Exposing fish to artificial light at night, not only made fish more active during the night, but also made them emerge quicker from hiding places during the day, which could increase their exposure to predators. Nocturnal lighting, however, did not affect their swimming speed or social behaviour during the day.
Artificial light at night also makes guppies more courageous during the day, according to a behavioural study led by researchers from IGB and the Max Planck Institute for Human Development. Exposing fish to artificial light at night, not only made fish more active during the night, but also made them emerge quicker from hiding places during the day, which could increase their exposure to predators. Nocturnal lighting, however, did not affect their swimming speed or social behaviour during the day.
Light pollution can have many influences on ecological processes. Previous research has shown that artificial light at night can have several direct consequences on night-time activity and movement patterns of animals. Many animal species, for example birds and insects, are attracted by artificial light sources at night and can, as a result, loose their orientation. But how artificial light at night impacts the behaviour of individuals during the day, when the source of light pollution is absent, is largely unknown. In this study, a team led by Ralf Kurvers of the MPI for Human Development in collaboration with the IGB, tested how exposure to artificial light at night affected the behaviour of fish during the day. As study species, they used guppies, a tropical freshwater fish and one of the model organisms of animal behavioural science. The scientists studied three groups of animals. Each group was exposed to the same bright light conditions during the day, but to different illuminations during the night. The first group experienced complete darkness at night; the second group was kept at a low light level at night, comparable to nocturnal illuminance under a street lamp; and the third group experienced bright light at night. After ten weeks of exposure, the scientists conducted behavioural tests to study the consequences of nightly light exposure on daytime behaviours.
Read more at Forschungsverbund Berlin
Image: Light pollution makes Guppys more courageous during the day. (Credit: David Bierbach, IGB)
