Corvo Island implements annual blackout to protect fledgling Cory's shearwaters
Each autumn, the inhabitants of Corvo Island in the Azores archipelago conduct a five-night blackout of public lighting to assist fledgling Cory's shearwaters. These young seabirds, which rely on starlight to navigate from their nests to the ocean, are frequently disoriented by artificial streetlights, leading them to crash into the village of Vila do Corvo. The initiative, which has been practiced by the island's approximately 450 residents since 2019, is part of a broader regional effort known as the SOS Cagarro campaign. Launched by the Azorean government in 1995, the campaign aims to protect the species across the archipelago. Volunteers and local residents actively search for and rescue disoriented birds during the blackout period, placing them in temporary care before releasing them near the ocean. Data from the campaign indicates that over 30,000 fledglings have been rescued across the Azores since 2015, with about 6,000 of those rescues occurring on Corvo.
Key points
- Corvo Island residents turn off public lights for five nights every autumn to prevent fledgling Cory's shearwaters from crashing into the village.
- Young shearwaters navigate to the ocean using starlight, but artificial light causes fatal disorientation.
- The SOS Cagarro campaign, launched in 1995, coordinates conservation efforts across the Azores.
- More than 30,000 shearwater fledglings have been rescued in the Azores since 2015, including 6,000 on Corvo.
- Rescued birds are held in cardboard boxes overnight and released near the ocean the following day.
Conservation through darkness
The initiative on Corvo Island addresses the impact of light pollution on the Cory's shearwater, a seabird endemic to the Atlantic Ocean. During their first flight from their nests to the ocean, juveniles are guided by the stars. Artificial illumination in Vila do Corvo has historically caused many birds to become confused and crash into the village streets.
Since 2019, the island's community has committed to a full blackout of public lighting for five nights each autumn. While household lights are not mandated to be turned off, many residents choose to do so voluntarily to support the birds' safe passage.
Regional impact and rescue efforts
The effort on Corvo is part of the wider SOS Cagarro campaign, which was established by the Azorean government in 1995 to protect shearwaters across all nine islands of the archipelago. The Portuguese Society for the Study of Birds (SPEA) also supports the project, which includes monitoring nests and using ultrasonic devices to deter predators like cats.
Volunteers and residents patrol the village during the blackout to locate disoriented birds. Rescued shearwaters are kept in cardboard boxes to recover before being released from cliffs near the ocean, providing them a second chance to reach their natural habitat.
Why it matters
The Corvo Island blackout demonstrates how targeted reductions in light pollution can mitigate ecological disruption for migratory seabirds. Since 2015, this collective effort has contributed to the rescue of over 30,000 Cory's shearwater fledglings across the Azores.
What we know
- Corvo Island residents have performed a five-night public lighting blackout each autumn since 2019 to protect fledgling Cory's shearwaters.
- The Azorean government launched the SOS Cagarro campaign in 1995 to protect shearwaters across the archipelago.
- More than 30,000 Cory's shearwater fledglings have been rescued in the Azores since 2015, with approximately 6,000 rescued on Corvo.
- Cory's shearwater fledglings use starlight to orient themselves during their first flight to the ocean.
