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Minnaar, C., Boyles, J. G., Minnaar, I. A., Sole, C. L., McKechnie, A. E., & McKenzie, A. (2014). Stacking the odds: light pollution may shift the balance in an ancient predator-prey arms race. J Appl Ecol, 52(2), 522–531.
Abstract: 1. Artificial night lighting threatens to disrupt strongly conserved light-dependent processes in animals and may have cascading effects on ecosystems as species interactions become altered. Insectivorous bats and their prey have been involved in a nocturnal, co-evolutionary arms race for millions of years. Lights may interfere with anti-bat defensive behaviours in moths, and disrupt a complex and globally ubiquitous interaction between bats and insects, ultimately leading to detrimental consequences for ecosystems on a global scale.
2. We combined experimental and mathematical approaches to determine effects of light pollution on a free-living bat–insect community. We compared prey selection by Cape serotine bats Neoromicia capensis in naturally unlit and artificially lit conditions using a manipulative field experiment, and developed a probabilistic model based on a suite of prey-selection factors to explain differences in observed diet. 3.Moth consumption by N. capensis was low under unlit conditions (mean percentage volume ± SD: 5·91 ± 6·25%), while moth consumption increased sixfold (mean percentage volume ± SD: 35·42 ± 17·90%) under lit conditions despite a decrease in relative moth abundance. Predictive prey-selection models that included high-efficacy estimates for eared-moth defensive behaviour found most support given diet data for bats in unlit conditions. Conversely, models that estimated eared-moth defensive behaviour as absent or low found more support given diet data for bats in lit conditions. Our models therefore suggest the increase in moth consumption was a result of light-induced, decreased eared-moth defensive behaviour. 4. Policy implications. In the current context of unyielding growth in global light pollution, we predict that specialist moth-eating bats and eared moths will face ever-increasing challenges to survival through increased resource competition and predation risk, respectively. Lights should be developed to be less attractive to moths, with the goal of reducing effects on moth behaviour. Unfortunately, market preference for broad-spectrum lighting and possible effects on other taxa make development of moth-friendly lighting improbable. Mitigation should therefore focus on the reduction of temporal, spatial and luminance redundancy in outdoor lighting. Restriction of light inside nature reserves and urban greenbelts can help maintain dark refugia for moth-eating bats and moths, and may become important for their persistence. |
Bissonnette, T. H. (1935). Modification of Mammalian Sexual Cycles. Journal of Experimental Biology, 12, 315–320.
Abstract: 1. Cases are given in which female ferrets, already coming into, or in, oestrus as the result of artificially increased lighting in winter and spring, underwent regression or were retarded in their activation by reduction of either intensity or duration of daily illumination.
2. In some cases activation was resumed when light time or intensity was increased again. 3. These results are taken to indicate that, in female ferrets, any inherent rhythm or cycle of sexual activity is modified either naturally or artificially by changes of the cycles of duration and intensity of the light to which they are exposed daily, and so made to correspond in phases with the seasons, or changed therefrom. The rising daily illumination in spring and the falling one in late summer and autumn probably accelerate and retard the sexual activity of the female ferret, or accelerate the onset of anoestrus in late summer and autumn. 4. The data on modification of sexual cycles or activity in ferrets, so far obtained, are consistent with these conclusions. Keywords: Animals
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Struyf P., Enhus E., Bauwens T., & Melgaço L. (2019). Literature study: The effects of reduced public lighting on crime, fear of crime, and road safety. west-vlaanderen, .
Abstract: 1. Introduction
1.1 Stating the problem: security versus climate and economic challenges Public street lighting as a public service is often taken for granted. However, its impact on the nocturnal perception of public space should not be underestimated. It encourages people to get out, feel safe, and be safe. Indeed, Welsh and Farrington suggest that public lighting enhances social control, cohesion, and a feeling of community pride (Welsh & Farrington, 2008b). According to (Williams, 2008), this is due to the special meaning attached to the darkness of night in society. It is associated with changes in social norms and values, transgression, the release of social control, feasting, drinking, and pleasure. Meanwhile, the darkness of night generates unpredictability, uncertainty and, therefore, fear. Illuminating the night chases away these feelings; people feel reassured and safer (Schivelbusch, 1995). Keywords: Safety; Security; Psychology; Review
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Van Geffen, K. G., Groot, A. T., Van Grunsven, R. H. A., Donners, M., Berendse, F., & Veenendaal, E. M. (2015). Artificial night lighting disrupts sex pheromone in a noctuid moth: Moth sex pheromone in illuminated nights. Ecol Entomol, 40(4), 401–408.
Abstract: 1. One major, yet poorly studied, change in the environment is the increase in nocturnal light pollution. Although this strongly alters the habitat of nocturnal species, the ecological consequences are poorly known. Moths are well known to be attracted to artificial light sources, but artificial light may affect them in other ways as well.
2. In this study, female Mamestra brassicae moths were subjected to various types of low-intensity artificial night lighting with contrasting spectral compositions (green-rich, red-rich, warm white) or to a dark control treatment and the effects on their sex pheromone production and composition were tested. 3. Artificial night lighting reduced sex pheromone production and altered the chemical composition of the pheromone blend, irrespective of spectral composition. Specifically, amounts of the main pheromone component Z11-16:Ac were reduced, while the deterring compounds Z9-14:Ac, Z9-16:Ac, and Z11-16:OH were increased relative to Z11-16:Ac when females were kept under artificial light. These changes may reduce the effectiveness of the sex pheromones, becoming less attractive for males. 4. These results show for the first time that artificial light at night affects processes that are involved in moth reproduction. The potential for mitigation through manipulation of the spectral composition of artificial light appears limited. |
BjÖRnberg, T. K. S., & Wilbur, K. M. (1968). Copepod Phototaxis And Vertical Migration Influenced By Xanthene Dyes. The Biological Bulletin, 134(3), 398–410.
Abstract: 1. Phototaxis of the copepods Paracalanus crassirostris, Calanopia americana, and Acartia lillijeborgi has been measured by determining the percentage of a population moving toward or away from a point source of light per unit time. Quantitative differences in positive phototaxis were found between the species. Photopositive responses differed during the day and night in Acartia but not in Paracalanus and Calanopia.
2. Rhodamine B (8.4 x 10-6 M) brought about the following effects: (a) Locomotor activity was reversibly inhibited in all species. (b) Photopositive responses were increased in Calanopia and Acartia but decreased in Paracalanus. (c) The difference between day and night responses to a point source of light was abolished in Acartia and induced in Calanopia. (d) Somersaulting was induced in Paracalanus but not in the other species. 3. Pyronine B (8.4 x 10-6 M) also decreased locomotor activity. Fluorescein sodium (1.1 x 10-5 M and 1.1 x 10-4 M) was without significant effect. 4. Paracalanus, Calanopia, and Acartia exhibited characteristically distinct diurnal migratory cycles in vertical cylinders, which correlated well with behavior in natural waters. Calanopia and Acartia migrated to the bottom in the daylight whereas Paracalanus and young forms of Acartia were widely distributed vertically during daylight. Specimens of Calanopia and Acartia kept in the dark did not migrate. 5. The effects of rhodamine B (8.4 x 10-6 M) on vertical migration depended upon species, developmental stage, and time of day. In general, rhodamine increased the concentration of animals at the surface at night and at the bottom in daylight. Fluorescein sodium (1.1 x 10-5 M and 1.1 x 10-4 M) had little effect on vertical migration. 6. The effectiveness of rhodamine B and pyronine B is probably related to the presence of diethylamine groups lacking in fluorescein. Keywords: Animals
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