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Author Muheim, R.; Phillips, J.B.; Akesson, S. url  doi
openurl 
  Title Polarized light cues underlie compass calibration in migratory songbirds Type Journal Article
  Year 2006 Publication Science (New York, N.Y.) Abbreviated Journal Science  
  Volume 313 Issue 5788 Pages 837-839  
  Keywords Alaska; *Animal Migration; Animals; Calibration; Cues; *Flight, Animal; Geography; *Light; Magnetics; *Orientation; Seasons; Sparrows/*physiology; Sunlight  
  Abstract Migratory songbirds use the geomagnetic field, stars, the Sun, and polarized light patterns to determine their migratory direction. To prevent navigational errors, it is necessary to calibrate all of these compass systems to a common reference. We show that migratory Savannah sparrows use polarized light cues from the region of sky near the horizon to recalibrate the magnetic compass at both sunrise and sunset. We suggest that skylight polarization patterns are used to derive an absolute (i.e., geographic) directional system that provides the primary calibration reference for all of the compasses of migratory songbirds.  
  Address Department of Animal Ecology, Lund University, Ecology Building, SE-223 62 Lund, Sweden. rmuheim@vt.edu  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0036-8075 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16902138 Approved no  
  Call Number IDA @ john @ Serial (down) 243  
Permanent link to this record
 

 
Author Doll, C.N.H.; Muller, J.-P.; Morley, J.G. url  doi
openurl 
  Title Mapping regional economic activity from night-time light satellite imagery Type Journal Article
  Year 2006 Publication Ecological Economics Abbreviated Journal Ecological Economics  
  Volume 57 Issue 1 Pages 75-92  
  Keywords Night-time light satellite imagery; Economic activity; Geographic information; Mapping; Scale  
  Abstract The recognition that the elements of the ‘anthropocene’ play a critical role in global change processes means that datasets describing elements of the socio-economic environment are becoming increasingly more desirable. The ability to present these data in a gridded format as opposed to the traditionally reported administrative units is advantageous for incorporation with other environmental datasets. Night-time light remote sensing data has been shown to correlate with national-level figures of Gross Domestic Product (GDP). Night-time radiance data is analysed here along with regional economic productivity data for 11 European Union countries along with the United States at a number of sub-national levels. Night-time light imagery was found to correlate with Gross Regional Product (GRP) across a range of spatial scales. Maps of economic activity at 5 km resolution were produced based on the derived relationships. To produce these maps, certain areas had to be excluded due to their anomalously high levels of economic activity for the amount of total radiance present. These areas were treated separately from other areas in the map. These results provide the first detailed examination of night-time light characteristics with respect to local economic activity and highlight issues, which should be considered when undertaking such analysis.  
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  Series Volume Series Issue Edition  
  ISSN 0921-8009 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial (down) 124  
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Author Sella, K.N.; Salmon, M.; Witherington, B.E. url  doi
openurl 
  Title Filtered Streetlights Attract Hatchling Marine Turtles Type Journal Article
  Year 2006 Publication Chelonian Conservation and Biology Abbreviated Journal Chelonian Conservation and Biology  
  Volume 5 Issue 2 Pages 255-261  
  Keywords Reptilia; Testudines; Cheloniidae; Loggerhead turtle; turtles; marine turtles; reptiles; Caretta caretta; Chelonia mydas; hatchlings; artificial lighting; light “trapping”; orientation; seafinding; Florida  
  Abstract On many nesting beaches, hatchling marine turtles are exposed to poled street lighting that disrupts their ability to crawl to the sea. Experiments were done to determine how hatchlings responded to street lighting transmitted through 2 filters that excluded the most disruptive wavelengths (those <&#8201;530 nm; those <&#8201;570 nm). Filtered lighting, however, also attracted the turtles though not as strongly as an unfiltered (high-pressure sodium vapor) lighting. Filtering is therefore of limited utility for light management, especially since other alternatives (such as lowering, shielding, or turning off unnecessary lighting; use of dimmer lights embedded in roadways) are more effective.  
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  ISSN 1071-8443 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial (down) 78  
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Author Baker, B.J.; Richardson, J.M.L. url  doi
openurl 
  Title The effect of artificial light on male breeding-season behaviour in green frogs,Rana clamitans melanota Type Journal Article
  Year 2006 Publication Canadian Journal of Zoology Abbreviated Journal Can. J. Zool.  
  Volume 84 Issue 10 Pages 1528-1532  
  Keywords animals; amphibians; frogs; green frogs; Rana clamitans melanota; Reproduction; reproductive strategies  
  Abstract Artificial night lighting (or ecological light pollution) is only now gaining attention as a source of long-term effects on the ecology of both diurnal and nocturnal animals. The limited data available clearly indicate that artificial light can affect physiology and behaviour of animals, leading to ecological consequences at the population, community, and ecosystem levels. Aquatic ecosystems may be particularly vulnerable to such effects, and nocturnally breeding animals such as frogs may be especially affected. To address this potential, we quantify the effects of artificial light on calling and movement behaviour in a rural population of male green frogs (Rana clamitans melanota (Rafinesque, 1820)) during the breeding season. When exposed to artificial light, frogs produced fewer advertisement calls and moved more frequently than under ambient light conditions. Results clearly demonstrate that male green frog behaviour is affected by the presence of artificial light in a manner that has the potential to reduce recruitment rates and thus affect population dynamics.  
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  ISSN 0008-4301 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial (down) 71  
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Author Takemura, A.; Ueda, S.; Hiyakawa, N.; Nikaido, Y. url  doi
openurl 
  Title A direct influence of moonlight intensity on changes in melatonin production by cultured pineal glands of the golden rabbitfish, Siganus guttatus Type Journal Article
  Year 2006 Publication Journal of Pineal Research Abbreviated Journal J Pineal Res  
  Volume 40 Issue 3 Pages 236-241  
  Keywords Animals; Circadian Rhythm; *Light; Melatonin/biosynthesis/*secretion; *Moon; Organ Culture Techniques; Perciformes/*physiology; Pineal Gland/physiology/*radiation effects  
  Abstract Rabbitfish are a restricted lunar-synchronized spawner that spawns around a species-specific lunar phase. It is not known how the fish perceive changes in cues from the moon. One possible explanation is that rabbitfish utilize changes in moonlight intensity to establish synchrony. The purpose of the present study was to examine whether or not the pineal gland of the golden rabbitfish can directly perceive changes in moonlight intensity. Isolated pineal glands were statically cultured under natural or artificial light conditions and melatonin secreted into the culture medium was measured using a time-resolved fluoroimmunoassay. Under an artificial light/dark cycle, melatonin secretion significantly increased during the dark phase. Under continuous light conditions, melatonin secretion was suppressed, while culture under continuous dark conditions seemed to duplicate melatonin secretion corresponding to the light/dark cycle in which the fish were acclimated. When cultured pineal glands were kept under natural light conditions on the dates of the full and the new moon, small amounts of melatonin were secreted at night. Moreover, exposure of cultured pineal glands to artificial and natural light conditions resulted in a significant decrease of melatonin secretion within 2 hr. These results suggest that the isolated pineal gland of golden rabbitfish responds to environmental light cycles and that 'brightness' of the night moon has an influence on melatonin secretion from the isolated pineal gland.  
  Address Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Motobu, Okinawa, Japan. tilapia@lab.u-ryukyu.ac.jp  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0742-3098 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16499560 Approved no  
  Call Number IDA @ john @ Serial (down) 70  
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