Avoidance of different durations, colours and intensities of artificial light by adult seabirds

Abstract

There is increasing evidence for impacts of light pollution on the physiology and behaviour of wild animals. Nocturnally active Procellariiform seabirds are often found grounded in areas polluted by light and struggle to take to the air again without human intervention. Hence, understanding their responses to different wavelengths and intensities of light is urgently needed to inform mitigation measures. Here, we demonstrate how different light characteristics can affect the nocturnal flight of Manx shearwaters Puffinus puffinus by experimentally introducing lights at a colony subject to low levels of light pollution due to passing ships and coastal developments. The density of birds in flight above the colony was measured using a thermal imaging camera. We compared number of flying shearwaters under dark conditions and in response to an artificially introduced light, and observed fewer birds in flight during ‘light-on’ periods, suggesting that adult shearwaters were repelled by the light. This effect was stronger with higher light intensity, increasing duration of ‘light-on’ periods and with green and blue compared to red light. Thus, we recommend lower light intensity, red colour, and shorter duration of ‘light-on’ periods as mitigation measures to reduce the effects of light at breeding colonies and in their vicinity.

Foraging Paths of Breeding Leach’s Storm-Petrels in Relation to Offshore Oil Platforms, Breeding Stage, and Year

“…There is, however, disagreement over the least attractive wavelengths to birds. Some studies have found that white and red light are the most attractive (Poot et al, 2008), whereas others have found that white, green, and blue light attract more migrating birds (Rebke et al, 2019;Syposz et al, 2021). The rapidly increasing use of bright LEDs, which are a major source of short blue wavelength light, is a problematic development (Rodríguez et al, 2017a;Hung et al, 2021).…”

“…These factors, as well as other aspects of foraging trip structure (duration, total distance, and location), may also vary within and among years. Annual differences in foraging location or behavior may reflect attraction to or avoidance of lit structures (e.g., Dierschke et al, 2016;Syposz et al, 2021), or could reflect shifts in prey distribution or availability (e.g., Burke and Montevecchi, 2009;Garthe et al, 2011). Withinyear differences could result from changing energetic demands through offspring development.…”

Impacts of artificial light at night in marine ecosystems—A review

“…Although there is a certain consensus about the higher pervasiveness of blue light for wildlife and, particularly, seabirds (Longcore et al, 2018; Rodríguez, Dann, & Chiaradia, 2017; Syposz et al, 2021), more research is needed on the spectrum of light in the perception of seabirds. Similarly, reductions in the duration of lights, by means of smart‐lighting or part‐night lighting, could help to mitigate light pollution impacts, but current understanding is insufficient to underpin sound recommendations for all species.…”

“…Thus, breeders could be deterred from visiting colonies when lights are turned on close to their nests or colonies. A recent experimental study on breeders of Manx shearwater Puffinus puffinus demonstrated that adult breeders flying over the colony were deterred by blue and green light in comparison to red light (Syposz et al, 2021). In addition, the number of birds flying over the colony decreased with the duration and intensity of light treatments (Syposz et al, 2021).…”

Discovery of the breeding colonies of a critically endangered and elusive seabird, the Mascarene Petrel (Pseudobulweria aterrima)

“…Infrared thermal binoculars are increasingly used in seabird ecology (e.g., Syposz et al 2021). In comparison to classic nocturnal detection tools such as night vision goggles or radar Burt-Toland 2009, Galase 2019), infrared thermal binoculars present strong advantages.…”