Natures wonders: Bird Migration by moonlight (Introduction)

by David Turell , Tuesday, October 15, 2019, 19:52 (1864 days ago) @ David Turell

First finding of its type. Nightjars use moonlight paterns:

https://www.newscientist.com/article/2219944-nightjars-time-their-epic-migration-flight...

"The European nightjar, which migrates from northern Europe to sub-Saharan Africa, seems to synchronise its flying with phases of the moon. It is the first time an animal’s migration patterns have been shown to be associated with the lunar cycle.

“'Most birds migrate at night, therefore the effect of moonlight on migration has always been an open question,” says Cecilia Nilsson at Cornell University in New York.

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"Their results reveal a key role of the full moon in the nightjar’s itinerary, which consists of long night-time flights with daytime resting punctuated by much longer rests at stopover sites. On moonlit nights, the birds’ foraging during migration stopovers more than doubled.

"Then, as the moon wanes, increasing numbers of nightjars embark on flights along their migration route, peaking at around 11 days after a full moon. Sometimes, all of the tracked birds would migrate simultaneously at this time in a great pulse.

"The team also found that the birds concentrate their feeding activity at dawn and dusk on most nights, only foraging through the night when there is plenty of moonlight.
Norevik says he and his team were astounded by how well the activity pattern of the birds followed the cycles of the moon. This is the first time moon phase has been identified as a regulator of migration schedule.

"Nilsson says these findings raise questions about the impact of artificial lights on any migrating birds relying on the lunar cycle. Light pollution is thought to be harmful to birds, but if the light of the full moon increases their foraging success, maybe artificial lighting could help them in that regard, acting as a bright, alternative moon."

Comment: Not surprising the moon is also used by some species. Warmer weather is always better, despite the current silly worries about global warming.