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Author Dacke, M.; Byrne, M.J.; Baird, E.; Scholtz, C.H.; Warrant, E.J. url  doi
openurl 
  Title How dim is dim? Precision of the celestial compass in moonlight and sunlight Type Journal Article
  Year 2011 Publication Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences Abbreviated Journal Philos Trans R Soc Lond B Biol Sci  
  Volume 366 Issue 1565 Pages 697-702  
  Keywords Animals; Beetles/*physiology; Behavior, Animal; *Moon; *Sunlight; Video Recording  
  Abstract Prominent in the sky, but not visible to humans, is a pattern of polarized skylight formed around both the Sun and the Moon. Dung beetles are, at present, the only animal group known to use the much dimmer polarization pattern formed around the Moon as a compass cue for maintaining travel direction. However, the Moon is not visible every night and the intensity of the celestial polarization pattern gradually declines as the Moon wanes. Therefore, for nocturnal orientation on all moonlit nights, the absolute sensitivity of the dung beetle's polarization detector may limit the precision of this behaviour. To test this, we studied the straight-line foraging behaviour of the nocturnal ball-rolling dung beetle Scarabaeus satyrus to establish when the Moon is too dim--and the polarization pattern too weak--to provide a reliable cue for orientation. Our results show that celestial orientation is as accurate during crescent Moon as it is during full Moon. Moreover, this orientation accuracy is equal to that measured for diurnal species that orient under the 100 million times brighter polarization pattern formed around the Sun. This indicates that, in nocturnal species, the sensitivity of the optical polarization compass can be greatly increased without any loss of precision.  
  Address Department of Biology, University of Lund, Helgonavagen 3, 223 62 Lund, Sweden. marie.dacke@cob.lu.se  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0962-8436 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21282173; PMCID:PMC3049003 Approved no  
  Call Number IDA @ john @ Serial 34  
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Author Kyba, C.C.M.; Hölker, F. url  doi
openurl 
  Title Do artificially illuminated skies affect biodiversity in nocturnal landscapes? Type Journal Article
  Year 2013 Publication Landscape Ecology Abbreviated Journal Landscape Ecol  
  Volume 28 Issue 9 Pages 1637-1640  
  Keywords skyglow; light pollution; biodiversity  
  Abstract The skyglow from cities at night is one of the most dramatic modifications that humans have made to Earth’s biosphere, and it is increasingly extending into nocturnal landscapes (nightscapes) far beyond urban areas. This scattered light is dim and homogenous compared to a lit street, but can be bright compared to natural celestial light sources, such as stars. Because of the large area of Earth affected by artificial skyglow, it is essential to verify whether skyglow is a selective pressure in nocturnal landscapes. We propose two scientific approaches that could examine whether skyglow affects biodiversity.  
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  Series Volume Series Issue Edition  
  ISSN 0921-2973 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 35  
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Author Hölker, F.; Wolter, C.; Perkin, E.K.; Tockner, K. url  doi
openurl 
  Title Light pollution as a biodiversity threat Type Journal Article
  Year 2010 Publication Trends in Ecology & Evolution Abbreviated Journal Trends Ecol Evol  
  Volume 25 Issue 12 Pages 681-682  
  Keywords *Biodiversity; Biological Clocks; Biological Evolution; Ecosystem; *Environmental Monitoring; *Environmental Pollutants; Light/*adverse effects  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0169-5347 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21035893 Approved no  
  Call Number IDA @ john @ Serial 36  
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Author Schoech, S.J.; Bowman, R.; Hahn, T.P.; Goymann, W.; Schwabl, I.; Bridge, E.S. url  doi
openurl 
  Title The effects of low levels of light at night upon the endocrine physiology of western scrub-jays (Aphelocoma californica) Type Journal Article
  Year 2013 Publication Journal of Experimental Zoology. Part A, Ecological Genetics and Physiology Abbreviated Journal J Exp Zool A Ecol Genet Physiol  
  Volume 319 Issue 9 Pages 527-538  
  Keywords Animals; Corticosterone/blood; Ecosystem; Female; *Light; Male; Melatonin/blood; Passeriformes/*physiology; *Photoperiod; Reproduction/*physiology; Testosterone/blood  
  Abstract Florida scrub-jays (Aphelocoma coerulescens) in the suburbs breed earlier than jays in native habitat. Amongst the possible factors that influence this advance (e.g., food availability, microclimate, predator regime, etc.), is exposure to artificial lights at night (LAN). LAN could stimulate the reproductive axis of the suburban jays. Alternatively, LAN could inhibit pineal melatonin (MEL), thus removing its inhibitory influence on the reproductive axis. Because Florida scrub-jays are a threatened species, we used western scrub-jays (Aphelocoma californica) to investigate the effects of LAN upon reproductive hormones and melatonin. Jays were held under conditions in which the dark-phase of the light:dark cycle was without illumination and then under low levels of LAN. Under both conditions, birds were exposed first to short-days (9.5L:14.5D) that were gradually increased to long-days (14.5L:9.5D). At various times, blood samples were collected during the light part of the cycle to measure reproductive hormones (luteinizing hormone, LH; testosterone, T; and estradiol, E2 ). Similarly, samples to assess melatonin were collected during the dark. In males, LAN caused a depression in LH levels and levels were approximately 4x greater under long- than short-days. In females, there was no effect of LAN or photoperiod upon LH. LAN resulted in depressed T levels in females, although there was no effect on T in males. E2 levels in both sexes were lower under LAN than under an unlighted dark-phase. Paradoxically, MEL was higher in jays under LAN, and under long-days. MEL did not differ by sex. LAN disrupted the extraordinarily strong correlation between T and E2 that existed under unlighted nocturnal conditions. Overall, our findings fail to support the hypothesis that LAN stimulates the reproductive axis. Rather, the data demonstrate that LAN tends to inhibit reproductive hormone secretion, although not in a consistent fashion between the sexes.  
  Address Department of Biological Sciences, University of Memphis, Memphis, Tennessee  
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  ISSN 1932-5223 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23970442 Approved no  
  Call Number IDA @ john @ Serial 37  
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Author Rodrí­guez, A.; Rodrí­guez, B.; Lucas, M.P. url  doi
openurl 
  Title Trends in numbers of petrels attracted to artificial lights suggest population declines in Tenerife, Canary Islands Type Journal Article
  Year 2012 Publication Ibis Abbreviated Journal  
  Volume 154 Issue 1 Pages 167-172  
  Keywords Animals; birds; petrels; Cory's shearwater; Calonectris diomedea; Bulwer's Petrel; Bulweria bulwerii; Macaronesian Shearwater; Puffinus baroli; reproductive strategies  
  Abstract The secretive breeding behaviour of petrels makes monitoring their breeding populations challenging. To assess population trends of Cory's Shearwater Calonectris diomedea, Bulwer's Petrel Bulweria bulwerii and Macaronesian Shearwater Puffinus baroli in Tenerife from 1990 to 2010, we used data from rescue campaigns that aim to reduce the mortality of fledgling petrels attracted to artificial lights as proxies for trends in breeding population size. Despite increases in human population size and light pollution, the number of rescued fledglings of Cory's Shearwater and Bulwer's Petrel increased and remained stable, respectively, whereas numbers of rescued Macaronesian Shearwaters sharply declined. In the absence of more accurate population estimates, these results suggest a worrying decline in the Macaronesian Shearwater's breeding population.  
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  Series Volume Series Issue Edition  
  ISSN 0019-1019 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 38  
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