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Bengsen, A. J., Leung, L. K. P., Lapidge, S. J., & Gordon, I. J. (2010). Artificial illumination reduces bait-take by small rainforest mammals. Applied Animal Behaviour Science, 127(1-2), 66–72.
Abstract: Small mammals often moderate their foraging behaviour in response to cues indicating a high local predation risk. We assessed the ability of cues associated with a high predation risk to reduce the consumption of bait by non-target small mammal species in a tropical rainforest, without inhibiting bait-take by feral pigs (Sus scrofa). The illumination of feeding stations with a low power light source caused small mammals to reduce their foraging intensity on sunflower seeds mixed through sand by 25% (P< 0.001) and on unprocessed corn-based feral pig bait by 80% (P< 0.001). Illumination also reduced the intensity with which small mammals fed on commercially manufactured baits (odds ratio. = 6.17, P= 0.009). Illumination did not cause pigs to reduce their intake of corn bait (P= 0.43). Neither pig nor dingo (Canis lupus dingo) vocalisations had any detectable effect on the foraging intensity of small mammals (P> 0.05 for all treatments). We conclude that site illumination was an effective method of selectively deterring small mammals from consuming feral pig baits in our study region, but had no effect on consumption of those baits by pigs.
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Prugh, L. R., & Golden, C. D. (2013). Does moonlight increase predation risk? Meta-analysis reveals divergent responses of nocturnal mammals to lunar cycles. J Anim Ecol, 83(2), 504–514.
Abstract: The risk of predation strongly affects mammalian population dynamics and community interactions. Bright moonlight is widely believed to increase predation risk for nocturnal mammals by increasing the ability of predators to detect prey, but the potential for moonlight to increase detection of predators and the foraging efficiency of prey has largely been ignored. Studies have reported highly variable responses to moonlight among species, calling into question the assumption that moonlight increases risk. Here, we conducted a quantitative meta-analysis examining the effects of moonlight on the activity of 59 nocturnal mammal species to test the assumption that moonlight increases predation risk. We examined patterns of lunarphilia and lunarphobia across species in relation to factors such as trophic level, habitat cover preference and visual acuity. Across all species included in the meta-analysis, moonlight suppressed activity. The magnitude of suppression was similar to the presence of a predator in experimental studies of foraging rodents (13.6% and 18.7% suppression, respectively). Contrary to the expectation that moonlight increases predation risk for all prey species, however, moonlight effects were not clearly related to trophic level and were better explained by phylogenetic relatedness, visual acuity and habitat cover. Moonlight increased the activity of prey species that use vision as their primary sensory system and suppressed the activity of species that primarily use other senses (e.g. olfaction, echolocation), and suppression was strongest in open habitat types. Strong taxonomic patterns underlay these relationships: moonlight tended to increase primate activity, whereas it tended to suppress the activity of rodents, lagomorphs, bats and carnivores. These results indicate that visual acuity and habitat cover jointly moderate the effect of moonlight on predation risk, whereas trophic position has little effect. While the net effect of moonlight appears to increase predation risk for most nocturnal mammals, our results highlight the importance of sensory systems and phylogenetic history in determining the level of risk.
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Topping, M. G., Millar, J. S., & Goddard, J. A. (1999). The effects of moonlight on nocturnal activity in bushy-tailed wood rats (Neotoma cinerea). Can. J. Zool., 77(3), 480–485.
Abstract: The nocturnal activity of bushy-tailed wood rats (Neotoma cinerea) was monitored for two breeding seasons (1993 and 1994) in the Canadian Rockies. Radiotelemetry was used under three levels of moonlight to assess two measures of nocturnal activity: (i) the proportion of animals crossing rocky outcrops and entering the surrounding forest to forage, search for mates, or both, and (ii) the distance moved from the den site while in the forest. Males and females exhibited significant differences among moonlight levels, with greater activity on nights of intermediate-level moonlight and less activity on nights with bright or dark moonlight. There was no difference in the proportions of males and females active at any moonlight level. The distances moved from the den did not differ among moonlight levels for either males or females. Having traversed the rocks and entered the forest, individuals moved similar distances regardless of light level. These results suggest that wood rats respond to moonlight only when making the decision to cross rocks and enter the forest. This behaviour presumably serves to counteract the increased risk of predation on bright nights.
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