Response of the Baikal littoral amphipod Eulimnogammarus cyaneus (Dybowsky, 1874) to warm and cold LED light of low intensities

Light pollution is currently becoming widespread throughout the world and affects both individual organisms and ecosystems. It was shown that light with different spectral characteristics affects organisms differently. Lake Baikal is also subject to light pollution. Light pollution on the lake tends to increase due to the growth of tourist flow and infrastructure development. Therefore, in this work we decided to evaluate the reaction of the amphipod Eulimnogammarus cyaneus, which is widespread in the littoral of Lake Baikal, to artificial light of different spectral characteristics and intensities. In a series of experiments, individuals were given a choice between warm (with a color temperature of 3200 K) and cold (5600 K) lighting or darkness. In the experiments, the illumination level was set at 2 lx or 10 lx. As a result, we found that warm and cold light had an effect on the behavior of individuals compared to the control. However, we did not find any difference in the behavior of amphipods when comparing warm and cold lighting. Furthermore, no differences were found between the response of individuals under cold light with 2 lx and 10 lx. However, the intensity of warm light is important for amphipods. A weak light avoidance response (demonstrated by E. cyaneus) may increase the frequency of detection of individuals of this species by predators in areas of the littoral of Lake Baikal subject to light pollution.