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Author Eriksen, A.; Wabakken, P.
Title Activity patterns at the Arctic Circle: nocturnal eagle owls and interspecific interactions during continuous midsummer daylight Type Journal Article
Year 2018 Publication Journal of Avian Biology Abbreviated Journal J Avian Biol
Volume 49 Issue 7 Pages e01781
Keywords Animals
Abstract Circadian rhythms result from adaptations to biotic and abiotic environmental conditions that cycle through the day, such as light, temperature, or temporal overlap between interacting species. At high latitudes, close to or beyond the polar circles, uninterrupted midsummer daylight may pose a challenge to the circadian rhythms of otherwise nocturnal species, such as eagle owls Bubo bubo. By non‐invasive field methods, we studied eagle owl activity in light of their interactions with their main prey the water vole Arvicola amphibius, and their competitor the white‐tailed eagle Haliaeetus albicilla during continuous midsummer daylight on open, treeless islands in coastal Northern Norway. We evaluated circadian rhythms, temporal overlap, exposure, and spatial distribution. The owls maintained a nocturnal activity pattern, possibly because slightly dimmer light around midnight offered favourable hunting conditions. The eagles were active throughout the 24‐hour period as opposed to the strictly diurnal rhythm reported elsewhere, thus increasing temporal overlap and the potential for interference competition between the two avian predators. This may indicate an asymmetry, with the owls facing the highest cost of interference competition. The presence of eagles combined with constant daylight in this open landscape may make the owls vulnerable to interspecific aggression, and contrary to the available literature, eagle owls rarely exposed themselves visually during territorial calls, possibly to avoid detection by eagles. We found indications of spatial segregation between owls and eagles reflecting differences in main prey, possibly in combination with habitat‐mediated avoidance. Eagle owl vocal activity peaked in the evening before a nocturnal peak in visual observations, when owls were active hunting, consistent with the hypothesis of a dusk chorus in nocturnal bird species. The owls may have had to trade‐off between calling and foraging during the few hours around midnight when slightly dimmer light reduced the detection risk while also providing better hunting conditions.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0908-8857 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 1881
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Author Holveck, M.-J.; Grégoire, A.; Doutrelant, C.; Lambrechts, M.M.
Title Nest height is affected by lamppost lighting proximity in addition to nestbox size in urban great tits Type Journal Article
Year 2018 Publication Journal of Avian Biology Abbreviated Journal J Avian Biol
Volume in press Issue Pages
Keywords Animals
Abstract Both natural and artificial light have proximate influences on many aspects of avian biology, physiology and behaviour. To date artificial light at night is mostly considered as being a nuisance disrupting for instance sleep and reproduction of diurnal species. Here, we investigate if lamppost night lighting affects cavity‐nesting bird species inside their breeding cavity. Nest height in secondary cavity‐nesting species is the result of trade‐offs between several selective forces. Predation is the prevailing force leading birds to build thin nests to increase the distance towards the entrance hole. A thin nest may also limit artificial light exposure at night. Yet, a minimum level of daylight inside nesting cavities is necessary for adequate visual communication and/or offspring development. Against this background, we hypothesised that avian nest‐building behaviour varies in response to a change in night lighting. We monitored nest height of urban great tits (Parus major) during six years and found that it varied with artificial light proximity. The birds built thinner nests inside nestboxes of various sizes in response to increasing lamppost night light availability at the nest. In large nestboxes, the nests were also thinner when a lamppost was present in the territory. Whether this relationship between artificial night lighting and nest height reflects a positive or negative effect of urbanisation is discussed in the light of recent experimental studies conducted in rural populations by other research groups.
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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 (up) 0908-8857 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2062
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Author Zhao, N.; Cao, G.; Zhang, W.; Samson, E.L.
Title Tweets or nighttime lights: Comparison for preeminence in estimating socioeconomic factors Type Journal Article
Year 2018 Publication ISPRS Journal of Photogrammetry and Remote Sensing Abbreviated Journal ISPRS Journal of Photogrammetry and Remote Sensing
Volume 146 Issue Pages 1-10
Keywords Remote Sensing
Abstract Nighttime lights (NTL) imagery is one of the most commonly used tools to quantitatively study socioeconomic systems over large areas. In this study we aim to use location-based social media big data to challenge the primacy of NTL imagery on estimating socioeconomic factors. Geo-tagged tweets posted in the contiguous United States in 2013 were retrieved to produce a tweet image with the same spatial resolution of the NTL imagery (i.e., 0.00833° × 0.00833°). Sum tweet (the total number of tweets) and sum light (summed DN value of the NTL image) of each state or county were obtained from the tweets and the NTL images, respectively, to estimate three important socioeconomic factors: personal income, electric power consumption, and fossil fuel carbon dioxide emissions. Results show that sum tweet is a better measure of personal income and electric power consumption while carbon dioxide emissions can be more accurately estimated by sum light. We further exploited that African-Americans adults are more likely than White seniors to post geotagged tweets in the US, yet did not find any significant correlations between proportions of the subpopulations and the estimation accuracy of the socioeconomic factors. Existence of saturated pixels and blooming effects and failure to remove gas flaring reduce quality of NTL imagery in estimating socioeconomic factors, however, such problems are nonexistent in the tweet images. This study reveals that the number of geo-tagged tweets has great potential to be deemed as a substitute of brightness of NTL to assess socioeconomic factors over large geographic areas.
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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 (up) 0924-2716 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 1994
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Author Taufique, S.K.T.; Prabhat, A.; Kumar, V.
Title Illuminated night alters hippocampal gene expressions and induces depressive-like responses in diurnal corvids Type Journal Article
Year 2018 Publication The European Journal of Neuroscience Abbreviated Journal Eur J Neurosci
Volume in press Issue Pages in press
Keywords Animals
Abstract Artificial light at night induces circadian disruptions and causes cognitive impairment and mood disorders; yet very little is known about the neural and molecular correlates of these effects in diurnal animals. We manipulated the night environment and examined cellular and molecular changes in hippocampus, the brain region involved in cognition and mood, of Indian house crows (Corvus splendens) exposed to 12 h light (150 lux): 12 h darkness (0 lux). Diurnal corvids are an ideal model species with cognitive abilities at par with mammals. Dim light (6 lux) at night (dLAN) altered daily activity:rest pattern, reduced sleep and induced depressive-like responses (decreased eating and self-grooming, self-mutilation and reduced novel object exploration); return to an absolute dark night reversed these negative effects. dLAN suppressed nocturnal melatonin levels, however, diurnal corticosterone levels were unaffected. Concomitant reduction of immunoreactivity for DCX and BDNF suggested dLAN-induced suppression of hippocampal neurogenesis and compromised neuronal health. dLAN also negatively influenced hippocampal expression of genes associated with depressive-like responses (bdnf, il-1beta, tnfr1, nr4a2), but not of those associated with neuronal plasticity (egr1, creb, syngap, syn2, grin2a, grin2b), cellular oxidative stress (gst, sod3, cat1) and neuronal death (caspase2, caspase3, foxo3). Furthermore, we envisaged the role of BDNF and showed epigenetic modification of bdnf gene by decreased histone H3 acetylation and increased hdac4 expression under dLAN. These results demonstrate transcriptional and epigenetic bases of dLAN-induced negative effects in diurnal crows, and provide insights into the risks of exposure to illuminated nights to animals including humans in an urban setting. This article is protected by copyright. All rights reserved.
Address IndoUS Center for Biological Timing Department of Zoology, University of Delhi, Delhi, 110 007, India
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 (up) 0953-816X ISBN Medium
Area Expedition Conference
Notes PMID:30218624 Approved no
Call Number GFZ @ kyba @ Serial 2010
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Author Leise, T.L.; Goldberg, A.; Michael, J.; Montoya, G.; Solow, S.; Molyneux, P.; Vetrivelan, R.; Harrington, M.E.
Title Recurring circadian disruption alters circadian clock sensitivity to resetting Type Journal Article
Year 2018 Publication The European Journal of Neuroscience Abbreviated Journal Eur J Neurosci
Volume in press Issue Pages
Keywords Animals
Abstract A single phase advance of the light:dark (LD) cycle can temporarily disrupt synchrony of neural circadian rhythms within the suprachiasmatic nucleus (SCN) and between the SCN and peripheral tissues. Compounding this, modern life can involve repeated disruptive light conditions. To model chronic disruption to the circadian system, we exposed male mice to more than a month of a 20 h light cycle (LD10:10), which mice typically cannot entrain to. Control animals were housed under LD12:12. We measured locomotor activity and body temperature rhythms in vivo, and rhythms of PER2::LUC bioluminescence in SCN and peripheral tissues ex vivo. Unexpectedly, we discovered strong effects of the time of dissection on circadian phase of PER2::LUC bioluminescent rhythms, which varied across tissues. White adipose tissue was strongly reset by dissection, while thymus phase appeared independent of dissection timing. Prior light exposure impacted the SCN, resulting in strong resetting of SCN phase by dissection for mice housed under LD10:10, and weak phase shifts by time of dissection in SCN from control LD12:12 mice. These findings suggest that exposure to circadian disruption may desynchronize SCN neurons, increasing network sensitivity to perturbations. We propose that tissues with a weakened circadian network, such as the SCN under disruptive light conditions, or with little to no coupling, e.g., some peripheral tissues, will show increased resetting effects. In particular, exposure to light at inconsistent circadian times on a recurring weekly basis disrupts circadian rhythms and alters sensitivity of the SCN neural pacemaker to dissection time. This article is protected by copyright. All rights reserved.
Address Neuroscience Program, Smith College, Northampton, MA, 01063, USA
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 (up) 0953-816X ISBN Medium
Area Expedition Conference
Notes PMID:30269396 Approved no
Call Number GFZ @ kyba @ Serial 2036
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