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Author Spoelstra, K.; Verhagen, I.; Meijer, D.; Visser, M.E. url  doi
openurl 
  Title Artificial light at night shifts daily activity patterns but not the internal clock in the great tit (Parus major) Type Journal Article
  Year 2018 Publication Proceedings. Biological Sciences Abbreviated Journal Proc Biol Sci  
  Volume (down) 285 Issue 1875 Pages  
  Keywords Animals  
  Abstract Artificial light at night has shown a dramatic increase over the last decades and continues to increase. Light at night can have strong effects on the behaviour and physiology of species, which includes changes in the daily timing of activity; a clear example is the advance in dawn song onset in songbirds by low levels of light at night. Although such effects are often referred to as changes in circadian timing, i.e. changes to the internal clock, two alternative mechanisms are possible. First, light at night can change the timing of clock controlled activity, without any change to the clock itself; e.g. by a change in the phase relation between the circadian clock and expression of activity. Second, changes in daily activity can be a direct response to light ('masking'), without any involvement of the circadian system. Here, we studied whether the advance in onset of activity by dim light at night in great tits (Parus major) is indeed attributable to a phase shift of the internal clock. We entrained birds to a normal light/dark (LD) cycle with bright light during daytime and darkness at night, and to a comparable (LDim) schedule with dim light at night. The dim light at night strongly advanced the onset of activity of the birds. After at least six days in LD or LDim, we kept birds in constant darkness (DD) by leaving off all lights so birds would revert to their endogenous, circadian system controlled timing of activity. We found that the timing of onset in DD was not dependent on whether the birds were kept at LD or LDim before the measurement. Thus, the advance of activity under light at night is caused by a direct effect of light rather than a phase shift of the internal clock. This demonstrates that birds are capable of changing their daily activity to low levels of light at night directly, without the need to alter their internal clock.  
  Address Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), PO Box 50, 6700 AB Wageningen, The Netherlands  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:29593108 Approved no  
  Call Number GFZ @ kyba @ Serial 1830  
Permanent link to this record
 

 
Author Dananay, K.L.; Benard, M.F. url  doi
openurl 
  Title Artificial light at night decreases metamorphic duration and juvenile growth in a widespread amphibian Type Journal Article
  Year 2018 Publication Proceedings of the Royal Society B: Biological Sciences Abbreviated Journal Proc. R. Soc. B  
  Volume (down) 285 Issue 1882 Pages 20180367  
  Keywords Animals  
  Abstract Artificial light at night (ALAN) affects over 20% of the earth's surface and is estimated to increase 6% per year. Most studies of ALAN have focused on a single mechanism or life stage. We tested for indirect and direct ALAN effects that occurred by altering American toads' (Anaxyrus americanus) ecological interactions or by altering toad development and growth, respectively. We conducted an experiment over two life stages using outdoor mesocosms and indoor terraria. In the first phase, the presence of ALAN reduced metamorphic duration and periphyton biomass. The effects of ALAN appeared to be mediated through direct effects on toad development, and we found no evidence for indirect effects of ALAN acting through altered ecological interactions or colonization. In the second phase, post-metamorphic toad growth was reduced by 15% in the ALAN treatment. Juvenile-stage ALAN also affected toad activity: in natural light, toads retreated into leaf litter at night whereas ALAN toads did not change behaviour. Carry-over effects of ALAN were also present; juvenile toads that had been exposed to larval ALAN exhibited marginally increased activity. In this time frame and system, our experiments suggested ALAN's effects act primarily through direct effects, rather than indirect effects, and can persist across life stages.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1951  
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Author Arendt, J.; Middleton, B. url  doi
openurl 
  Title Human seasonal and circadian studies in Antarctica (Halley, 75 degrees S) Type Journal Article
  Year 2018 Publication General and Comparative Endocrinology Abbreviated Journal Gen Comp Endocrinol  
  Volume (down) 258 Issue Pages 250-258  
  Keywords Human Activities; Acclimatization/*physiology; Actigraphy; Adult; Antarctic Regions; Behavior/*physiology; Circadian Rhythm/*physiology; Darkness; Female; Heart Rate/physiology; Humans; Libido; Light; Male; Melatonin/blood; Photoperiod; *Seasons; Sleep/physiology; Young Adult; *Antarctica; *Circadian; *Light; *Melatonin; *Seasonal  
  Abstract Living for extended periods in Antarctica exposes base personnel to extremes of daylength (photoperiod) and temperature. At the British Antarctic Survey base of Halley, 75 degrees S, the sun does not rise for 110 d in the winter and does not set for 100 d in summer. Photoperiod is the major time cue governing the timing of seasonal events such as reproduction in many species. The neuroendocrine signal providing photoperiodic information to body physiology is the duration of melatonin secretion which reflects the length of the night: longer in the short days of winter and shorter in summer. Light of sufficient intensity and spectral composition serves to suppress production of melatonin and to set the circadian timing and the duration of the rhythm. In humans early observations suggested that bright (>2000 lux) white light was needed to suppress melatonin completely. Shortly thereafter winter depression (Seasonal Affective Disorder or SAD) was described, and its successful treatment by an artificial summer photoperiod of bright white light, sufficient to shorten melatonin production. At Halley dim artificial light intensity during winter was measured, until 2003, at a maximum of approximately 500 lux in winter. Thus a strong seasonal and circadian time cue was absent. It seemed likely that winter depression would be common in the extended period of winter darkness and could be treated with an artificial summer photoperiod. These observations, and predictions, inspired a long series of studies regarding human seasonal and circadian status, and the effects of light treatment, in a small overwintering, isolated community, living in the same conditions for many months at Halley. We found little evidence of SAD, or change in duration of melatonin production with season. However the timing of the melatonin rhythm itself, and/or that of its metabolite 6-sulphatoxymelatonin (aMT6s), was used as a primary marker of seasonal, circadian and treatment changes. A substantial phase delay of melatonin in winter was advanced to summer phase by a two pulse 'skeleton' bright white light treatment. Subsequently a single morning pulse of bright white light was effective with regard to circadian phase and improved daytime performance. The circadian delay evidenced by melatonin was accompanied by delayed sleep (logs and actigraphy): poor sleep is a common complaint in Polar regions. Appropriate extra artificial light, both standard white, and blue enriched, present throughout the day, effectively countered delay in sleep timing and the aMT6s rhythm. The most important factor appeared to be the maximum light experienced. Another manifestation of the winter was a decline in self-rated libido (men only on base at this time). Women on the base showed lower aspects of physical and mental health compared to men. Free-running rhythms were seen in some subjects following night shift, but were rarely found at other times, probably because this base has strongly scheduled activity and leisure time. Complete circadian adaptation during a week of night shift, also seen in a similar situation on North Sea oil rigs, led to problems readapting back to day shift in winter, compared to summer. Here again timed light treatment was used to address the problem. Sleep, alertness and waking performance are critically dependent on optimum circadian phase. Circadian desynchrony is associated with increased risk of major disease in shift workers. These studies provide some groundwork for countering/avoiding circadian desynchrony in rather extreme conditions.  
  Address Biochemistry and Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK. Electronic address: b.middleton@surrey.ac.uk  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0016-6480 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:28526480 Approved no  
  Call Number IDA @ john @ Serial 2248  
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Author Pulgar, J.; Zeballos, D.; Vargas, J.; Aldana, M.; Manriquez, P.; Manriquez, K.; Quijon, P.A.; Widdicombe, S.; Anguita, C.; Quintanilla, D.; Duarte, C. url  doi
openurl 
  Title Endogenous cycles, activity patterns and energy expenditure of an intertidal fish is modified by artificial light pollution at night (ALAN) Type Journal Article
  Year 2018 Publication Environmental Pollution (Barking, Essex : 1987) Abbreviated Journal Environ Pollut  
  Volume (down) 244 Issue Pages 361-366  
  Keywords Animals  
  Abstract The increase of global light emissions in recent years has highlighted the need for urgent evaluation of their impacts on the behaviour, ecology and physiology of organisms. Numerous species exhibit daily cycles or strong scototaxic behaviours that could potentially be influenced if natural lighting conditions or cycles are disrupted. Artificial Light Pollution at Night (ALAN) stands for situations where artificial light alters natural light-dark cycles, as well as light intensities and wavelengths. ALAN is increasingly recognized as a potential threat to biodiversity, mainly because a growing number of studies are demonstrating its influence on animal behaviour, migration, reproduction and biological interactions. Most of these studies have focused on terrestrial organisms and ecosystems with studies on the effects of ALAN on marine ecosystems being more occasional. However, with the increasing human use and development of the coastal zone, organisms that inhabit shallow coastal or intertidal systems could be at increasing risk from ALAN. In this study we measured the levels of artificial light intensity in the field and used these levels to conduct experimental trials to determine the impact of ALAN on an intertidal fish. Specifically, we measured ALAN effects on physiological performance (oxygen consumption) and behaviour (activity patterns) of “Baunco” the rockfish Girella laevifrons, one of the most abundant and ecologically important intertidal fish in the Southeastern Pacific littoral. Our results indicated that individuals exposed to ALAN exhibited increased oxygen consumption and activity when compared with control animals. Moreover, those fish exposed to ALAN stopped displaying the natural (circatidal and circadian) activity cycles that were observed in control fish throughout the experiment. These changes in physiological function and behaviour could have serious implications for the long-term sustainability of fish populations and indirect impacts on intertidal communities in areas affected by ALAN.  
  Address Departamento de Ecologia & Biodiversidad, Facultad de Ciencia de la Vida, Universidad Andres Bello, Chile; Center for the Study of Multiple-Drivers on Marine Socio-Ecological Systems (MUSELS), Universidad de Concepcion, Concepcion, Chile  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0269-7491 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30352350 Approved no  
  Call Number GFZ @ kyba @ Serial 2043  
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Author Grubisic, M.; van Grunsven, R.H.A.; Manfrin, A.; Monaghan, M.T.; Hölker, F. url  doi
openurl 
  Title A transition to white LED increases ecological impacts of nocturnal illumination on aquatic primary producers in a lowland agricultural drainage ditch Type Journal Article
  Year 2018 Publication Environmental Pollution Abbreviated Journal Environmental Pollution  
  Volume (down) 240 Issue Pages 630-638  
  Keywords Plants; Ecology  
  Abstract The increasing use of artificial light at night (ALAN) has led to exposure of freshwater ecosystems to light pollution worldwide. Simultaneously, the spectral composition of nocturnal illumination is changing, following the current shift in outdoor lighting technologies from traditional light sources to light emitting diodes (LED). LEDs emit broad-spectrum white light, with a significant amount of photosynthetically active radiation, and typically a high content of blue light that regulates circadian rhythms in many organisms. While effects of the shift to LED have been investigated in nocturnal animals, its impact on primary producers is unknown. We performed three field experiments in a lowland agricultural drainage ditch to assess the impacts of a transition from high-pressure sodium (HPS) to white LED illumination (color temperature 4000 K) on primary producers in periphyton. In all experiments, we compared biomass and pigment composition of periphyton grown under a natural light regime to that of periphyton exposed to nocturnal HPS or, consecutively, LED light of intensities commonly found in urban waters (approximately 20 lux). Periphyton was collected in time series (1–13 weeks). We found no effect of HPS light on periphyton biomass; however, following a shift to LED the biomass decreased up to 62%. Neither light source had a substantial effect on pigment composition. The contrasting effects of the two light sources on biomass may be explained by differences in their spectral composition, and in particular the blue content. Our results suggest that spectral composition of the light source plays a role in determining the impacts of ALAN on periphyton and that the ongoing transition to LED may increase the ecological impacts of artificial lighting on aquatic primary producers. Reduced biomass in the base of the food web can impact ecosystem functions such as productivity and food supply for higher trophic levels in nocturnally-lit ecosystems.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0269-7491 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1900  
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