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Author Santos, C.D.; Miranda, A.C.; Granadeiro, J.P.; Lourenço, P.M.; Saraiva, S.; Palmeirim, J.M. url  doi
openurl 
  Title Effects of artificial illumination on the nocturnal foraging of waders Type Journal Article
  Year 2010 Publication Acta Oecologica Abbreviated Journal Acta Oecologica  
  Volume 36 Issue 2 Pages 166-172  
  Keywords waders; light pollution; animals  
  Abstract Large areas of natural and semi-natural habitats are exposed to artificial illumination from adjacent urban areas and roads. Estuarine and coastal wetlands are particularly exposed to such illumination because shorelines often are heavily utilized by man. However, the impact of artificial illumination on the waders that forage in these highly productive habitats is virtually unknown. We evaluated the effects of artificial illumination on the nocturnal habitat selection and foraging behaviour of six wader species with different feeding strategies: three visual foragers, two species that alternate visual and tactile strategies (mixed foragers), and one tactile forager. We quantified the number of birds and their foraging behaviour at sites affected and not affected by streetlights, and also before and after illuminating experimental sites. Areas illuminated by streetlights were used more during the night by visual foragers, and to a lesser extent by mixed foragers, than non-illuminated areas. Visual foragers increased their foraging effort in illuminated areas, and mixed foragers changed to more efficient visual foraging strategies. These behavioural shifts improved prey intake rate by an average of 83% in visual and mixed foragers. We have showed that artificial illumination has a positive effect on the nocturnal foraging of waders, but on the other hand may draw them to degraded areas close to urban centres, and potentially raises their exposure to predators. Our findings suggest that artificial illumination is worth investigation as a tool in the management of intertidal habitats for waders.  
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  ISSN 1146609X ISBN Medium (down)  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 46  
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Author Rojas, L.M.; McNeil, R.; Cabana, T.; Lachapelle, P. url  doi
openurl 
  Title Diurnal and Nocturnal Visual Capabilities in Shorebirds as a Function of Their Feeding Strategies Type Journal Article
  Year 1999 Publication Brain, Behavior and Evolution Abbreviated Journal Brain Behav Evol  
  Volume 53 Issue 1 Pages 29-43  
  Keywords foraging; Catoptrophorus semipalmatus; Territorial Willets; Black-winged Stilt; Himantopus himantopus; Scolopax minor; Limnodromus griseus; birds; Wilson's Plover; Charadrius wilsonia; Short-billed Dowitcher; Limnodromus griseus  
  Abstract Some shorebird species forage with the same feeding strategy at night and during daytime, e.g. visual pecking in the Wilson's Plover (Charadrius wilsonia) or tactile probing in the Short-billed Dowitcher (Limnodromus griseus). The Limnodromus griseus (Scolopax minor) uses tactile probing, by day and by night, but sometimes pecks for insects during daytime. The Black-winged Stilt (Himantopus himantopus) is a visual pecker, both by day and by night, and sometimes forages tactilely on windy (agitated water surface) moonless nights. Territorial Willets (Catoptrophorus semipalmatus) are visual peckers during daylight and on moonlight conditions but switch to tactile feeding under lower light conditions. It could be postulated that some shorebird species would switch from visual feeding during daytime to tactile foraging at night because they have poor night vision compared to species that are always sight foragers irrespective of the time of the day. This issue was examined by comparing retinal structure and function in the above species. Electroretinograms (ERGs) were obtained at different light intensities from anesthetized birds, and the retinae were processed for histological observations. Based on ERGs, retinal sensitivity, and rod:cone ratios, both plovers and stilts are well adapted for nocturnal vision. Although they have low rod density compared to that of stilts and plovers, Willets and woodcocks have a scotopic retinal sensitivity similar to that of stilts and plovers but rank midway between plovers and dowitchers for the b-wave amplitude. Dowitchers have the lowest scotopic b-wave amplitude and retinal sensitivity and appear the least well adapted for night vision. Based on photopic ERGs and cone densities, although stilts, Willets and dowitchers appear as well adapted for daytime vision, plovers occupy the last rank of all species examined. Compared to the nighttime tactile feeders and those that switch from daytime visual pecking to tactile feeding at night, nighttime sight feeders have a superior rod function and, consequently, potentially superior nocturnal visual capabilities.  
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  Series Volume Series Issue Edition  
  ISSN 0006-8977 ISBN Medium (down)  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 47  
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Author Jetz, W.; Steffen, J.; Linsenmair, K.E. url  doi
openurl 
  Title Effects of light and prey availability on nocturnal, lunar and seasonal activity of tropical nightjars Type Journal Article
  Year 2003 Publication Oikos Abbreviated Journal Oikos  
  Volume 103 Issue 3 Pages 627-639  
  Keywords foraging; Caprimulgus climacurus; birds; nightjars; standard-winged nightjar; Macrodipteryx longipennis; long-tailed nightjar  
  Abstract Nightjars and their allies represent the only major group of visually hunting aerial insectivores with a crepuscular and/or nocturnal lifestyle. Our purpose was to examine how both light regime and prey abundance in the tropics, where periods of twilight are extremely short, but nightjar diversity is high, affect activity across different temporal scales. We studied two nightjar species in West African bush savannah, standard-winged nightjars Macrodipteryx longipennis Shaw and long-tailed nightjars Caprimulgus climacurus Vieillot. We measured biomass of potential prey available using a vehicle mounted trap and found that it was highest at dusk and significantly lower at dawn and during the night. Based on direct observations, both nightjars exhibit the most intense foraging behaviour at dusk, less intense foraging at dawn and least at night, as predicted by both prey abundance and conditions for visual prey detection. Nocturnal foraging was positively correlated with lunar light levels and ceased below about 0.03 mW m−2. Over the course of a lunar cycle, nocturnal light availability varied markedly, while prey abundance remained constant at dusk and at night was slightly higher at full moon. Both species increased twilight foraging activity during new moon periods, compensating for the shorter nocturnal foraging window at that time. Seasonally, the pattern of nocturnal light availability was similar throughout the year, while prey availability peaked shortly after onset of the wet season and then slowly decreased over the following four months. The courtship and breeding phenology of both species was timed to coincide with the peak in aerial insect abundance, suggesting that prey availability rather than direct abiotic factors act as constraints, at least at the seasonal level. Our findings illustrate the peculiar constraints on visually orienting aerial nocturnal insectivores in general and tropical nightjars in particular and highlight the resulting nocturnal, lunar and seasonal allocation of activities.  
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  ISSN 0030-1299 ISBN Medium (down)  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 48  
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Author Dominoni, D.M.; Quetting, M.; Partecke, J. url  doi
openurl 
  Title Long-term effects of chronic light pollution on seasonal functions of European blackbirds (Turdus merula) Type Journal Article
  Year 2013 Publication PloS one Abbreviated Journal PLoS One  
  Volume 8 Issue 12 Pages e85069  
  Keywords Turdus merula; European blackbird; birds; animals; Reproduction  
  Abstract Light pollution is known to affect important biological functions of wild animals, including daily and annual cycles. However, knowledge about long-term effects of chronic exposure to artificial light at night is still very limited. Here we present data on reproductive physiology, molt and locomotor activity during two-year cycles of European blackbirds (Turdus merula) exposed to either dark nights or 0.3 lux at night. As expected, control birds kept under dark nights exhibited two regular testicular and testosterone cycles during the two-year experiment. Control urban birds developed testes faster than their control rural conspecifics. Conversely, while in the first year blackbirds exposed to light at night showed a normal but earlier gonadal cycle compared to control birds, during the second year the reproductive system did not develop at all: both testicular size and testosterone concentration were at baseline levels in all birds. In addition, molt sequence in light-treated birds was more irregular than in control birds in both years. Analysis of locomotor activity showed that birds were still synchronized to the underlying light-dark cycle. We suggest that the lack of reproductive activity and irregular molt progression were possibly the results of i) birds being stuck in a photorefractory state and/or ii) chronic stress. Our data show that chronic low intensities of light at night can dramatically affect the reproductive system. Future studies are needed in order to investigate if and how urban animals avoid such negative impact and to elucidate the physiological mechanisms behind these profound long-term effects of artificial light at night. Finally we call for collaboration between scientists and policy makers to limit the impact of light pollution on animals and ecosystems.  
  Address Department of Migration and Immuno-ecology, Max Planck Institute for Ornithology, Radolfzell, Germany ; Department of Biology, University of Konstanz, Konstanz, Germany  
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  Language English Summary Language Original Title  
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  ISSN 1932-6203 ISBN Medium (down)  
  Area Expedition Conference  
  Notes PMID:24376865; PMCID:PMC3869906 Approved no  
  Call Number IDA @ john @ Serial 49  
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Author Dominoni, D.; Quetting, M.; Partecke, J. url  doi
openurl 
  Title Artificial light at night advances avian reproductive physiology Type Journal Article
  Year 2013 Publication Proceedings. Biological Sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume 280 Issue 1756 Pages 20123017  
  Keywords Animals; *Lighting; Male; Molting; Photoperiod; Reproduction/*physiology; Singing; Songbirds/*physiology; Testis/anatomy & histology; Testosterone/blood; Trees  
  Abstract Artificial light at night is a rapidly increasing phenomenon and it is presumed to have global implications. Light at night has been associated with health problems in humans as a consequence of altered biological rhythms. Effects on wild animals have been less investigated, but light at night has often been assumed to affect seasonal cycles of urban dwellers. Using light loggers attached to free-living European blackbirds (Turdus merula), we first measured light intensity at night which forest and city birds are subjected to in the wild. Then we used these measurements to test for the effect of light at night on timing of reproductive physiology. Captive city and forest blackbirds were exposed to either dark nights or very low light intensities at night (0.3 lux). Birds exposed to light at night developed their reproductive system up to one month earlier, and also moulted earlier, than birds kept under dark nights. Furthermore, city birds responded differently than forest individuals to the light at night treatment, suggesting that urbanization can alter the physiological phenotype of songbirds. Our results emphasize the impact of human-induced lighting on the ecology of millions of animals living in cities and call for an understanding of the fitness consequences of light pollution.  
  Address Department of Migration and Immuno-ecology, Max Planck Institute for Ornithology, Radolfzell 78315, Germany. ddominoni@orn.mpg.de  
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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 (down)  
  Area Expedition Conference  
  Notes PMID:23407836; PMCID:PMC3574380 Approved no  
  Call Number IDA @ john @ Serial 50  
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