@article{EccardSchefflerFrankeetal.2018,
  author    = {Eccard, Jana and Scheffler, Ingo and Franke, Steffen and Hoffmann, Julia},
  title     = {Off-grid},
  series = {Insect conservation and diversity},
  volume    = {11},
  journal   = {Insect conservation and diversity},
  number    = {6},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {1752-458X},
  doi       = {10.1111/icad.12303},
  pages     = {600 -- 607},
  year      = {2018},
  abstract  = {1. Advances in LED technology combined with solar, storable energy bring light to places remote from electricity grids. Worldwide more than 1.3 billion of people are living off-grid, often in developing regions of high insect biodiversity. In developed countries, dark refuges for wildlife are threatened by ornamental garden lights. Solar powered LEDs (SPLEDs) are cheaply available, dim, and often used to illuminate foot paths, but little is known on their effects on ground living (epigeal) arthropods. 2. We used off-the-shelf garden lamps with a single 'white' LED (colour temperature 7250 K) to experimentally investigate effects on attraction and nocturnal activity of ground beetles (Carabidae). 3. We found two disparate and species-specific effects of SPLEDs. (i) Some nocturnal, phototactic species were not reducing activity under illumination and were strongly attracted to lamps (>20-fold increase in captures compared to dark controls). Such species aggregate in lit areas and SPLEDs may become ecological traps, while the species is drawn from nearby, unlit assemblages. (ii) Other nocturnal species were reducing mobility and activity under illumination without being attracted to light, which may cause fitness reduction in lit areas. 4. Both reactions offer mechanistic explanations on how outdoor illumination can change population densities of specific predatory arthropods, which may have cascading effects on epigeal arthropod assemblages. The technology may thus increase the area of artificial light at night (ALAN) impacting insect biodiversity. 5. Measures are needed to mitigate effects, such as adjustment of light colour temperature and automated switch-offs.},
  language  = {en}
}
@phdthesis{Hoffmann2021,
  author    = {Hoffmann, Julia},
  title     = {Influence of artificial light at night on the behavior of small mammals},
  school      = {Universit{\"a}t Potsdam},
  pages     = {115},
  year      = {2021},
  abstract  = {Artificial light at night (ALAN), one form of human-induced rapid environmental change, is continuously spreading in space and time and increasing in intensity as part of the ongoing urbanization. A vast range of animals is known to be affected by ALAN as, among other things, it can mask natural light cues and change both the perceived as well as the actual predation risk. Since ALAN per se is restricted to the night, the majority of studies so far have focused on nocturnal species or behavioral changes during the night. How polyphasic species respond to ALAN has been largely overlooked, although they can possibly carry over effects of nighttime illumination into the day. Additionally, individuals within a species are known to consistently differ in their personality which includes risk-taking behavior. While this implies that ALAN can lead to varying anti-predatory responses in animals within a population, knowledge on this topic is still very limited. This thesis aims at investigating what initial behavioral reaction is caused by ALAN in polyphasic small mammals while also incorporating an animal's personality. Nighttime and daytime activity, movement and foraging behavior of the bank vole (Myodes glareolus) were investigated in regards to effects of different light intensities and partial illumination in the laboratory. Additionally, changes in intra- and interspecific interactions of bank voles and striped field mice (Apodemus agrarius) subjected to ALAN were studied in experimental populations in semi-natural outdoor enclosures. Chapter I explores whether behavioral responses to ALAN of varying intensity are related to animal personality. Results showed that bank voles reduced movement and foraging already under dim light and that bold animals generally moved and foraged more than shy animals. Exclusively under bright illumination did bold animals exploit the food patches more than shy animals. The results demonstrate that bank voles are affected by light intensities prevalent in urban habitats. Additionally, certain light scenarios might lead to an advantage of and a shift towards certain personality types. Chapter II focusses on the effects of partial ALAN on foraging behavior of animals with varying animal personalities while extending the view towards possible carry-over effects of ALAN into the daytime. While bank voles reduced foraging behavior in illuminated areas at night, they increased foraging behavior in those areas at the subsequent day. Bold individuals generally had lower giving-up densities than shy individuals but this difference was especially pronounced during daytime at formerly illuminated food patches. Thus, ALAN can have carry-over effects into the daytime in polyphasic animals and thus has the potential to affect daytime intra- and interspecific interactions. Chapter III broadens the view from the individual to the population level. Experimental populations consisting of bank voles and striped field mice were established in large outdoor enclosures successively experienced natural and artificial light conditions at night. VHF telemetry data revealed that animals were predominantly active during the day under natural conditions. This difference between day and night vanished under ALAN. Additionally, conspecifics reduced home range overlap, proximity and activity synchrony while boldness was not associated with behavioral changed due to ALAN. The results suggest that ALAN has the potential to alter intraspecific interactions and thus can have fitness consequences on the population level. Overall, the present thesis shows that ALAN can affect nighttime and daytime behavior as well as intraspecific interactions of polyphasic small mammals. Differences in risk- taking behavior of individuals may vary in importance depending on other environmental variables. Thus, this thesis hopefully triggers broadening the view regarding the role of an animal's personality in coping with ALAN and the effects on daytime behavior and diurnal species.},
  language  = {en}
}
@article{HoffmannHoelkerEccard2022,
  author    = {Hoffmann, Julia and H{\"o}lker, Franz and Eccard, Jana},
  title     = {Welcome to the dark side},
  series = {Frontiers in ecology and evolution},
  volume    = {9},
  journal   = {Frontiers in ecology and evolution},
  publisher = {Frontiers Media},
  address   = {Lausanne},
  issn      = {2296-701X},
  doi       = {10.3389/fevo.2021.779825},
  pages     = {11},
  year      = {2022},
  abstract  = {Differences in natural light conditions caused by changes in moonlight are known to affect perceived predation risk in many nocturnal prey species. As artificial light at night (ALAN) is steadily increasing in space and intensity, it has the potential to change movement and foraging behavior of many species as it might increase perceived predation risk and mask natural light cycles. We investigated if partial nighttime illumination leads to changes in foraging behavior during the night and the subsequent day in a small mammal and whether these changes are related to animal personalities. We subjected bank voles to partial nighttime illumination in a foraging landscape under laboratory conditions and in large grassland enclosures under near natural conditions. We measured giving-up density of food in illuminated and dark artificial seed patches and video recorded the movement of animals. While animals reduced number of visits to illuminated seed patches at night, they increased visits to these patches at the following day compared to dark seed patches. Overall, bold individuals had lower giving-up densities than shy individuals but this difference increased at day in formerly illuminated seed patches. Small mammals thus showed carry-over effects on daytime foraging behavior due to ALAN, i.e., nocturnal illumination has the potential to affect intra- and interspecific interactions during both night and day with possible changes in personality structure within populations and altered predator-prey dynamics.},
  language  = {en}
}
@misc{HoffmannHoelkerEccard2022,
  author    = {Hoffmann, Julia and H{\"o}lker, Franz and Eccard, Jana},
  title     = {Welcome to the Dark Side},
  series = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-54470},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-544702},
  pages     = {13},
  year      = {2022},
  abstract  = {Differences in natural light conditions caused by changes in moonlight are known to affect perceived predation risk in many nocturnal prey species. As artificial light at night (ALAN) is steadily increasing in space and intensity, it has the potential to change movement and foraging behavior of many species as it might increase perceived predation risk and mask natural light cycles. We investigated if partial nighttime illumination leads to changes in foraging behavior during the night and the subsequent day in a small mammal and whether these changes are related to animal personalities. We subjected bank voles to partial nighttime illumination in a foraging landscape under laboratory conditions and in large grassland enclosures under near natural conditions. We measured giving-up density of food in illuminated and dark artificial seed patches and video recorded the movement of animals. While animals reduced number of visits to illuminated seed patches at night, they increased visits to these patches at the following day compared to dark seed patches. Overall, bold individuals had lower giving-up densities than shy individuals but this difference increased at day in formerly illuminated seed patches. Small mammals thus showed carry-over effects on daytime foraging behavior due to ALAN, i.e., nocturnal illumination has the potential to affect intra- and interspecific interactions during both night and day with possible changes in personality structure within populations and altered predator-prey dynamics.},
  language  = {en}
}
@article{HoffmannHoelkerEccard2022,
  author    = {Hoffmann, Julia and H{\"o}lker, Franz and Eccard, Jana},
  title     = {Welcome to the Dark Side},
  series = {Frontiers in Ecology and Evolution},
  volume    = {9},
  journal   = {Frontiers in Ecology and Evolution},
  publisher = {Frontiers Media},
  address   = {Lausanne},
  issn      = {2296-701X},
  doi       = {10.3389/fevo.2021.779825},
  pages     = {11},
  year      = {2022},
  abstract  = {Differences in natural light conditions caused by changes in moonlight are known to affect perceived predation risk in many nocturnal prey species. As artificial light at night (ALAN) is steadily increasing in space and intensity, it has the potential to change movement and foraging behavior of many species as it might increase perceived predation risk and mask natural light cycles. We investigated if partial nighttime illumination leads to changes in foraging behavior during the night and the subsequent day in a small mammal and whether these changes are related to animal personalities. We subjected bank voles to partial nighttime illumination in a foraging landscape under laboratory conditions and in large grassland enclosures under near natural conditions. We measured giving-up density of food in illuminated and dark artificial seed patches and video recorded the movement of animals. While animals reduced number of visits to illuminated seed patches at night, they increased visits to these patches at the following day compared to dark seed patches. Overall, bold individuals had lower giving-up densities than shy individuals but this difference increased at day in formerly illuminated seed patches. Small mammals thus showed carry-over effects on daytime foraging behavior due to ALAN, i.e., nocturnal illumination has the potential to affect intra- and interspecific interactions during both night and day with possible changes in personality structure within populations and altered predator-prey dynamics.},
  language  = {en}
}