Ecolights for seabirds - News

New publication: Safe haven-type shelters mitigate light-induced mortality

9/8/2025

Strandings of procellariiform (tube-nosed) seabirds can be greatly reduced by decreasing emissions of artificial light at night, but in many affected locations (e.g., cities, industrial sites) it is impractical or impossible to entirely eliminate artificial light. Thus, it is important to understand post-stranding behaviour of the affected species, from which we can develop mitigation measures for predation-related mortality. We experimentally studied post-stranding behavioural responses to artificial light by stranded Leach’s Storm-petrel (Hydrobates leucorhous) fledglings in three different contexts: 1) by quantifying phototactic responses toward and preferences among various light types in a Y-maze choice experiment; 2) by measuring activity levels under various light types in an open field; and 3) by determining the propensity of fledglings to hide in a provided “Safe Haven” shelter box under light versus dark conditions in the same open field. Stranded storm-petrel fledglings generally displayed an aversion to light, whereby individuals predominantly chose to remain in the darker portions of the Y-maze where they were initially placed. They also displayed higher activity levels in light compared to dark conditions, which appeared to be part of a negatively phototactic response given that more than half of tested individuals entered the “Safe Haven” under light conditions, while zero sought shelter in darkness. Safe Haven-type shelters hold promise as an effective tool to mitigate post-stranding seabird mortality in anthropogenic spaces near breeding colonies that continue to be illuminated by artificial light at night.
More info at:
Brown TM, et al. 2025. Under cover of darkness: Refuge from artificial light at night may mitigate risks to stranded seabirds. Ornithological Applications

A Leach's storm-petrel pokes its head out of a "Safe Haven" shelter box (an empty, repurposed rodent bait station) during an experimental trial. Photo: T. Brown.

Multiple Leach's storm-petrels sheltered together overnight inside a "Safe Haven" box deployed at a stranding hotspot in Newfoundland, Canada, during a mass stranding event. Photo: T. Brown.

Pufflings navigating the lit night

9/6/2025

Y-maze choice experiment to study phototaxis. Photo: Taylor Brown,

Each year in Newfoundland, Canada, fledgling Atlantic Puffins (“pufflings”; Fratercula arctica) become stranded in coastal towns during their nocturnal first flights from breeding colonies on nearby islands. We tested the hypothesis that stranding in this species is caused by phototaxis toward artificial light. We did so by alternately illuminating two dark beaches facing the same breeding colony, monitoring both beaches (one light, one dark) every night and counting the number of pufflings observed at each. Over 11 nights, we observed an estimated 136 pufflings when the beaches were illuminated, and only two when the beaches were dark, supporting our hypothesis. On a finer scale, we also tested post-stranding behavioural responses to and preferences among artificial light types and brightness levels by stranded pufflings in a Y-maze choice experiment. Individuals displayed positive phototaxis in this experiment by preferentially choosing the illuminated versus dark arm of the apparatus; however, they displayed no significant preferences among the various light types and brightness levels tested. Our results suggest that, regardless of light type, coastal artificial light emissions should be reduced as much as possible in coastal areas near Atlantic Puffin breeding colonies to reduce stranding rates and resultant mortality.

More info at:
Brown TM, et al. 2024. Navigating the night: effects of artificial light on the behaviour of Atlantic puffin fledglings. Animal Behaviour

Red, amber and white: light attraction in adult fairy prion

2/19/2025

The lighting rig in action (A) and a fairy prion (B). Photo: K. L. Middlemiss

The impact from light in marine systems is poorly understood, despite evidence that vessel lighting can cause seabird disorientation and collisions. We investigated the effects of LED colour and lumen output on attraction/disorientation in adult fairy prion (Pachyptila turtur) at Stephen’s Island, New Zealand. Fairy prions are known to interact with vessels at night. We used red, amber, and white lights, at varying lumen outputs, to measure attraction/disorientation responses, and looked at environmental factors that may affect these responses. Fairy prions were most impacted by white lights and high lumen output with increasing levels of attraction/disorientation from red to amber to white, and at higher levels of brightness. We also found that bright moonlight and higher wind speeds decreased attraction/disorientation responses, while higher relative humidity increased the responses. While there were insufficient groundings to statistically test the effect of light colour, the same pattern of increasing impact seemed to be present. Interestingly, we were also able to predict the ranking of the species’ response to each light treatment’s colour spectrum and lumen output based on the species’ optical sensitivity to different wavelengths (using the species’ spectral response curve). Our findings highlight the need to consider both LED colour and lumen output, alongside environmental conditions, and in our paper, we provide several recommendations for the design of mitigation measures that reduce anthropogenic lighting impacts on land and at sea.
More info at:
Middlemiss K, et al. 2025. Understanding the Impacts of LED Light Pollution in Marine Ecosystems: Phototaxis Response in Fairy Prion. Journal of Ornithology

Number of fairy prions that grounded across all experimental nights in the different light treatments

Understanding light preferences of Procellariiformes

2/4/2025

Cory's shearwater in the Y-maze exposed to red and blue light. Photo: E Atchoi.

A novel paper investigates the behavioural preferences of both fledgling and adult Cory’s shearwaters (Calonectris borealis) to different light stimuli and evaluates this behaviour against the observed vulnerability to light that young shearwaters display. Using a Y-maze experiment, researchers found that both age groups preferred darkness and red light over blue or white light, suggesting that shorter-wavelength light disrupts their navigation. Fledglings, in particular, showed slower reactions and signs of disorientation when exposed to artificial light, which supports the observation that the majority of rescued birds affected by light are fledglings. Adults, while also avoiding bright lights, reacted more quickly, likely due to their experience, navigating in different types of environments, including urban lit areas. Both groups behaviour suggests that shorter-wavelength light, like blue and white LEDs, is particularly disruptive, possibly interfering with the birds' ability to navigate. These findings highlight the importance of reducing artificial light pollution in coastal regions. Shifting to longer-wavelength lighting and minimizing unnecessary outdoor illumination could help protect seabirds during their critical fledging period.
More info at:
Atchoi E, et al. 2024. Do seabirds dream of artificial lights? Understanding light preferences of Procellariiformes. Journal of Experimental Biology
This paper is highlighted in "Blue and white light pollution is disastrous for Cory's shearwater fledglings" by Kathryn Knight in INSIDE JEB.

New Caledonia, a killing field for threatened Gould’s petrel and at least two other petrel species

12/14/2024

A new paper reports on a benevolent campaign to save petrels stranded in New Caledonia (Coral Sea) during three consecutive years. Three petrel species were the most commonly grounded: 80% were wedge-tailed shearwaters Ardenna pacifica, 14 % were Gould's petrels Pterodroma leucoptera, a threatened species, and 5 % were Tahiti petrels Pseudobulweria rostrata, near-threatened.
Petrel groundings were mapped at the scales of both New Caledonia’s main island (Grande Terre) and Grande Terre’s main city (Nouméa). Combining all three species, an estimated 65% of grounded individuals were fledglings. Groundings of Gould's petrels and wedge-tailed shearwaters peaked during their respective fledging seasons, i.e. April and May. The number of lights and the proximity to shore were identified as highly significant positive factors explaining the number of groundings. Groundings were also recorded at densely-lit industrial sites and airports. Mortality upon discovery or within days after exceeded 48% in the wedge-tailed shearwater, 35% in Gould's petrel, and 23% in the Tahiti petrel. The results provide evidence to support the urgent implementation of artificial light reduction policies at the periphery of Nouméa, around industrial sites, and near airports, especially during the fledging periods of the wedge-tailed shearwater and Goulds’ petrel.

Nouméa's urban shoreline. Photo: DR.

Dead stranded Gould's petrel in Nouméa's streets. The neck was presumably bitten by a dog or a cat. Photo: IRD / P. Borsa.

Release of a rescued Gould’s petrel at a beach in Nouméa. Photo: IRD / P. Borsa.

More info at:
Borsa P, Mareschal J, Chartendrault V (2024) Light-induced petrel groundings in New Caledonia. Zoological Studies

Citizen science and remote sensing illuminate the Arctic

12/4/2024

This visualization illustrates how seabird diversity decreases with increasing artificial light intensity. Taken from Balazy et al. 2024.

This study explores the effects of Artificial Light at Night (ALAN) on seabird diversity during the Arctic polar night. Authors combined a decade of citizen science-based seabird observations from Longyearbyen, Svalbard, with remote sensing data on light intensity, sea ice presence, and air temperature. This comprehensive dataset allowed us to assess how environmental conditions, including light pollution, influence seabird assemblages in the High Arctic. Our findings reveal that ALAN significantly impacts seabird diversity in this region. While individual species vary in their response, the overall trend shows a negative effect, with ALAN reducing the diversity of seabird communities. These results highlight an urgent need to address light pollution as a growing threat to seabird populations, particularly as the Arctic faces dynamic changes, including ice-free conditions and increased human activity. By combining innovative methods —remote sensing and citizen science— this research offers novel insights into light pollution's ecological impacts. This study represents an important step toward the conservation of seabirds, one of the most globally threatened bird groups, and underscores the need for sustainable management practices in the rapidly changing Arctic environment.
More info at:
Balazy K, et al. 2024. Illuminating the Arctic: Unveiling seabird responses to artificial light during polar darkness through citizen science and remote sensing. Remote Sensing in Ecology and Conservation

Actions to minimize light attraction of adult seabirds

9/12/2024

Light attraction is a well–documented phenomenon affecting seabirds world–wide, but it is typically associated with fledglings. There is little in the literature regarding the impact on breeding adult seabirds on land. We document a large-scale fallout event of adult seabirds at a facility in the north-west of Kauaʻi. In September of 2015, 131 adult endangered seabirds including 123 ʻaʻo (Newell’s Shearwater Puffinus newelli) and 6 ʻuaʻu (Hawaiian Petrels Pterodroma sandwichensis) were grounded by lights at the Kōkeʻe Air Force Station – the majority occurring over a two-night period. This was caused by the proximity of the facility to large breeding colonies of the species coupled with bright, upward–facing, unshielded lights and nocturnal conditions that exacerbate the fallout phenomena - a waning moon (thus a dark night), with rain and fog. In response to this event, the facility altered its lighting protocol to use only shielded low–intensity light bollards (amber (590nm) 33 watts LED). Results from annual monitoring at the facility found only four grounded ‘a’o between 2016-2023 indicating that the new lighting regime dramatically reduced fallout. We use the results of this study to provide recommendations for best–practice light minimization methods in similar situations worldwide.

Lights at the facility during the fallout were bright green, unshielded and often upwards facing. Photo: André F Raine.

Lights after minimization were significantly reduced, consisting of bollards emitting a low wattage amber glow (590mm, 33 watts). Photo: André F Raine.

Grounded 'a'o (Newell's Shearwater) often crawled into very small dark spaces and were only found by dedicated searchers using flashlights. Photo: André F Raine.

More info at:
Raine AF, et al. 2024. The impact of light attraction on adult seabirds and the effectiveness of minimization actions. Pacific Science

Turn off the light and decrease seabird strandings

6/13/2024

The world’s largest colony of Leach’s Storm-Petrels (1.95 million pairs) is on Baccalieu Island, Newfoundland and Labrador (NL), Canada approximately 10 km away from the town of Bay de Verde, NL, Canada where there is a brightly illuminated seafood processing plant that has become a Leach’s Storm-Petrel stranding hotspot. We turned 12 of the 16 brightest lights on the front of the plant on and off according to a predetermined schedule, and recorded how many storm-petrels were stranded each night by performing daily morning counts as well as occasional night surveys. Daily morning and night surveys revealed that reducing artificial light at night significantly decreased Leach’s Storm-Petrel strandings, indicating that even partial light reductions can be effective in mitigating seabird strandings. These results provide experimental evidence to support the implementation of widespread reduction of coastal artificial light as a conservation strategy, especially during avian fledging and migration periods.

Photo. Photos taken in 2021 of the Quinlan Brothers Ltd. seafood processing plant with the LEDs on the front of the building on (A) and with nearly all of them off (B). Photos by S.M. Collins.

More info at:
Burt TV, et al. 2024. Reduction of coastal lighting decreases seabird strandings. PLoS One

New paper and cover! Moonlight diminishes seabird attraction to artificial light

10/27/2023

From the interior of its nest, a Cory's shearwater fledgling waits for the darkness of the night to fly for the first time to theocean. Interaction between artificial lights and the full moon affects the fledgling's success in reaching the sea. Image credit: Beneharo Rodríguez.

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(a) Mean number (± SD) of Cory's shearwater fledglings admitted to the rescue program in Tenerife, Canary Islands, during 31 years (1990–2021). Dots and error bars indicate the mean and SD of the number of rescued birds. The vertical red line represents the mean peak rescue date (November 4). (b) Cory's shearwater fledglings rescued in Tenerife during recent fledging seasons (2015–2021). The black line and the shaded gray area on each graph represent the nightly numbers of birds rescued. Vertical blue lines represent the full moon. Dots and error bars in gray indicate the mean and SD of the number of rescued birds during 31 years. Note the different Y-axis scales for 2015–2017 in relation to 2018–2021. (c) Annual numbers of Cory's shearwater fledglings rescued in Tenerife during 31 years (1990–2021). The full moon date indicates the difference in days with the mean peak rescue date, which we consider a proxy of the mean peak fledging date. Thus, negative values indicate an earlier full moon than November 4. Positive values indicate a later full moon. Zero indicates that the full moon coincided with the mean peak rescue date (November 4). Dots with light tones, that is, those representing years with full moon night around the mean peak rescue date, reach relatively low numbers of rescued birds in comparison to subsequent years. Taken from Rodríguez et al. 2023.

Rescue programs aiming to mitigate light-induced mortality of seabird fledglings have reported that fewer birds are grounded (and rescued) during full moon nights. Two non-mutually exclusive hypotheses have been proposed as explanations: (1) reduction of strandings because birds are less attracted to and disorientated by light pollution during full moon nights; and (2) reduction of fledging activity, that is, chicks avoid departing the colony during nights with increased moonlight. We argue that evidence from rescue programs and other studies supports the first but not the second hypothesis. The evidence supports the conclusion that a higher proportion of fledglings make it safely to sea during full moon nights than during moonless nights. Thus, there is a decrease in the severity of light pollution on seabirds around the full moon.
More info at:
Rodríguez A, et al. 2023. Moonlight diminishes seabird attraction to artificial light. Conservation Science and Practice

New publication!! Artificial lights pose risk to seabirds far from their natal colonies

8/8/2023

Over the course of five years over 4,648 wedge-tailed shearwaters were banded across nine colonies on O'ahu, Hawai’i to study the relationship between fallout location from light pollution and their natal colony (the colony they fledged from) to see if seabirds were experiencing fallout in close proximity to their fledging site. Surprisingly, we found that almost half of the birds in the study were experiencing fallout on opposite coastlines from their natal colonies and at much farther distances than predicted (average distance = >20km). One bird was even found on an opposite island over 100km away! Only one bird fledged from the colony closest to its fallout location. This research highlights the importance of mitigating light pollution for seabird conservation in an entire meta-population or island chain as lights anywhere could be contributing to fallout and that patterns of light-pollution-induced fallout in seabirds are less predictable and farther reaching than anticipated.

Dotted lines link the natal colonies (indicated as yellow markers) with the fallout locations (indicated as open circles) on O‘ahu, Hawai‘i. Locations of un-surveyed colonies are indicated as white markers. MCBH-KB = Marine Corps Base Hawaii Kaneohe Bay, KBP = Kailua Beach Park. The upper right corner shows the inter-island fallout event discovered on Maui of a bird banded at a colony on O‘ahu. Figure taken from the original paper.

More info at:
Friswold B, et al. 2023. From colony to fallout: Artificial lights pose risk to seabird fledglings far from their natal colonies. Conservation Science and Practice