Effects of experimental night lighting on the daily timing of winter foraging in common European songbirds

Abstract

The ecological effects of light pollution are becoming better understood, especially in birds. Recent studies have shown that several bird species can use street lighting to extend activity into the night during the breeding season. However, most of these studies are correlational and little is known about the effects of artificial night lighting on the timing of activities outside the breeding season. During winter, low temperatures and short days may limit foraging opportunities and can negatively affect survival of resident birds. However, night lighting may allow them to expand the time niche available for foraging. Here, we report on a study where we repeatedly manipulated the amount of night lighting during early winter at automated feeding stations in a natural forest. We used video-recordings at the feeders to determine the time of the first (at dawn) and last (at dusk) foraging visits for six songbird species. We predicted that all species, and in particular the naturally early-foraging species, would advance their daily onset of foraging during the mornings with night lighting, but would show minimal or no delays in their daily cessation of foraging during the lighted evenings. We found that two early-foraging species, the blue tit and the great tit, started foraging earlier during the experimentally lighted mornings. However, in great tits, this effect was weak and restricted to nights with inclement weather. The light treatment did not have any effect on the start of foraging in the willow/marsh tit, the nuthatch, the European jay, and the blackbird. Artificial night lighting did not cause later foraging at dusk in any of the six species. Overall, our results suggest that artificial light during winter has only small effects on timing of foraging. We discuss these findings and the importance of temperature and winter weather in shaping the observed foraging patterns.

Multisensory pollution: Artificial light at night and anthropogenic noise have interactive effects on activity patterns of great tits (Parus major)

“…Indeed, light advanced activity onset of up to two hours in some individuals, and consequently increased nighttime activity by an average of one hour per night. This result is in line with previous studies that have shown that artificial light at night can increase nocturnal restlessness as well as foraging behaviour in great tits and other diurnal bird species (78)(79)(80). These effects are likely to come through the impact of light on physiological processes such as clock gene expression and melatonin production (56,58).…”

A Case for a New Satellite Mission for Remote Sensing of Night Lights

“…ALAN is therefore a novel challenge to biological systems that evolved over billions of years in the presence of only natural conditions of nocturnal illumination. ALAN is known to disrupt physiological processes that rely on the daily and seasonal rhythms of light cues, such as foraging behaviors [29][30][31][32], timing of emergence [33][34][35][36], reproduction [37][38][39][40], communication [41][42][43], and migration [38,44]. ALAN has been explored as one of the factors that can lead to the disruption and weakening of interdependent ecological systems and food webs.…”

Impact of artificial light at night on the foraging behaviour of the European Hamster: consequences for the introduction of this species in suburban areas

“…For instance, ALAN disrupts circannual cycles, such as reproduction seasonality (Goldman 2001;Dominoni et al 2013;Robert et al 2015;Le Tallec et al 2016;Gaston et al 2017), which can lead to decreased reproductive success (Ikeno et al 2014;Cissé et al 2017 but see Stracey et al 2014 for increased reproductive success of birds). ALAN can also generate the appearance of a "night light niche" (Garber 1978;Russ et al 2015;Silva et al 2017), corresponding to the colonisation of the nocturnal niche by diurnal species and thus increasing interspecies competition and predation. Animals can also modify their foraging patterns in response to increased nocturnal visibility to reduce their risk of predation (reported in fishes: Clark and Levy 1988;Becker et al 2013, andin rodents: Clarke 1983;Kotler et al 1991;Bird et al 2004;Farnworth et al 2016).…”