Positive News reports that the Portuguese island of Corvo switched off its lights this week — not to save energy, but to help fledgling seabirds navigate by the stars.

Corvo Municipal Council has pledged to black out the island's streets and public buildings for almost three weeks beginning 21 October. The timing is deliberate: young Cory's shearwaters leave their nests over roughly four weeks from mid-October, relying on starlight to guide them toward the ocean.

The surprising part of this story is the stakes attached to a simple streetlight. Positive News explains that light pollution interferes with the fledglings' built-in navigation systems, luring the young birds inland where they crash and become stranded.

The species is not endangered, but around 75% of the world's breeding population nests in the Azores, and the birds can live up to 40 years while raising just a single chick a year — so every fledgling lost to artificial light genuinely counts against the global population.

A brief blackout, in other words, protects a meaningful share of the entire species' next generation.

The Corvo blackout lands amid wider scientific attention on how birds navigate long journeys. Houston Public Media's weekly panel recently weighed in on a study finding that birds can get jetlag when flying across the Atlantic, underscoring how sensitive avian navigation is to disruption.

For shearwater fledglings on Corvo, the challenge is even more immediate: their first flight depends entirely on reading the night sky accurately.

Positive News notes that when artificial glow drowns out those cues, the birds' in-built systems fail and the young shearwaters end up grounded on land instead of gliding out over open water.

The blackout is only one layer of a long-running rescue effort.

Positive News reports that since 1995, the Azores Government's SOS Cagarro campaign and SPEA, the Portuguese Society for the Study of Birds, have mobilised nightly rescue brigades across the archipelago to save stranded birds, and since 2019 communities have turned their lights off after dark during the fledgling season.

SPEA says the measures have proved effective in reducing the number of birds that become grounded or die in collisions. 'There are many ways to save a Cory's shearwater, and each person can help in their own way,' SPEA-Azores marine conservation technician Beatriz Martins told Positive News.

The blacked-out weeks now underway on Corvo will carry this year's cohort of fledglings through the bulk of their departure window from mid-October onward.

Positive News notes that residents are encouraged to help in practical ways — from switching off exterior lights to carrying a box, gloves and a towel in the car in case they find a downed bird, or alerting the authorities if they prefer not to handle one — and even joining the brigades themselves.

With the council's pledge running for almost three weeks, the island's skies should stay dark through the peak of the season, giving thousands of young birds a starlit path to the ocean.

What makes Corvo's blackout delightful is how simple and achievable it is: a small community, a determined council and a conservation charity aligning on a fix that costs nothing and works.

Positive News frames the story as proof that local action can meaningfully protect wildlife — in this case the world's largest population of Cory's shearwaters, of which about three quarters breed in the Azores.

For readers elsewhere, it offers a heartening template: when the next fledgling season arrives, the difference between a deadly glow and safe passage can literally be a switch on the wall, flipped by neighbours acting together.