Publication Details |
Category | Text Publication |
Reference Category | Journals |
DOI | 10.1016/j.scitotenv.2023.165760 |
Title (Primary) | Skyglow relieves a crepuscular bird from visual constraints on being active |
Author | Evens, R.; Lathouwers, M.; Pradervand, J.-N.; Jechow, A.; Kyba, C.C.M.; Shatwell, T.; Jacot, A.; Ulenaers, E.; Kempenaers, B.; Eens, M. |
Source Titel | Science of the Total Environment |
Year | 2023 |
Department | SEEFO |
Volume | 900 |
Page From | art. 165760 |
Language | englisch |
Topic | T5 Future Landscapes |
Keywords | Nightjar, Activity-logging; Artificial light; Time-niche; Anthropocene |
Abstract |
Artificial light at night significantly
alters the predictability of the natural light cycles that most animals use as
an essential Zeitgeber for daily activity. Direct light has well-documented
local impacts on activity patterns of diurnal and nocturnal organisms. However,
artificial light at night also contributes to an indirect illumination of the
night sky, called skyglow, which is rapidly increasing. The consequences of
this wide-spread form of artificial night light on the behaviour of animals
remain poorly understood, with only a few studies performed under controlled
(laboratory) conditions. Using animal-borne activity loggers, we investigated
daily and seasonal flight activity of a free-living crepuscular bird species in
response to nocturnal light conditions at sites differing dramatically in
exposure to skyglow. We find that flight activity of European Nightjars
(Caprimulgus europaeus) during moonless periods of the night is four times
higher in Belgium (high skyglow exposure) than in sub-tropical Africa and two times
higher than in Mongolia (near-pristine skies). Moreover, clouds darken the sky
under natural conditions, but skyglow can strongly increase local sky
brightness on overcast nights. As a result, we find that nightjars' response to
cloud cover is reversed between Belgium and sub-tropical Africa and between
Belgium and Mongolia. This supports the hypothesis that cloudy nights reduce
individual flight activity in a pristine environment, but increase it when the
sky is artificially lit. Our study shows that in the absence of direct light
pollution, anthropogenic changes in sky brightness relieve nightjars from
visual constraints on being active. Individuals adapt daily activities to
artificial night-sky brightness, allowing them more time to fly than conspecifics
living under natural light cycles. This modification of the nocturnal timescape
likely affects behavioural processes of most crepuscular and nocturnal species,
but its implications for population dynamics and interspecific interactions
remain to be investigated. |
Persistent UFZ Identifier | https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=27510 |
Evens, R., Lathouwers, M., Pradervand, J.-N., Jechow, A., Kyba, C.C.M., Shatwell, T., Jacot, A., Ulenaers, E., Kempenaers, B., Eens, M. (2023): Skyglow relieves a crepuscular bird from visual constraints on being active Sci. Total Environ. 900 , art. 165760 10.1016/j.scitotenv.2023.165760 |