|   | 
Author de Jong, M.; Jeninga, L.; Ouyang, J.Q.; van Oers, K.; Spoelstra, K.; Visser, M.E.
Title Dose-dependent responses of avian daily rhythms to artificial light at night Type Journal Article
Year 2015 Publication Physiology & Behavior Abbreviated Journal Physiol Behav
Volume 155 Issue Pages 172-179
Keywords Animals; Artificial light at night; Circadian rhythm; Dose-response; Great tit; Light intensity; Melatonin; Parus major
Abstract Recent studies have shown that animals are affected by night-time light exposure. Light is a continuous variable, but our knowledge on how individuals react to different light intensities during the night is limited. We therefore determined the relationship between night light intensity and the behaviour and physiology of great tits (Parus major). We measured daily activity patterns and melatonin levels in 35 males exposed to five different light intensities and found strong, dose-dependent effects. Activity onset was increasingly advanced, and activity offset delayed with higher light intensities. Furthermore, night-time activity increased and melatonin levels measured at midnight decreased with higher intensities. In this experimental study, we demonstrate for the first time dose-dependent effects of artificial light at night on birds' daily activity patterns and melatonin levels. Our results imply that these effects are not limited to a certain threshold, but emerge even when nocturnal light levels are slightly increased. However, in a natural area, these effects may be limited as artificial light levels are commonly low; light intensities drop rapidly with distance from a light source and birds can avoid exposure to light at night. Future studies should thus focus on examining the impact of different intensities of light at night in the wild.
Address Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, 6700 AB Wageningen, The Netherlands; m.dejong(at)nioo.knaw.nl
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor (up)
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9384 ISBN Medium
Area Expedition Conference
Notes PMID:26703233 Approved no
Call Number IDA @ john @ Serial 1327
Permanent link to this record