Why Are Coral Reefs Surrounded by Mysterious “Ghostly” Halos?

Why Are Coral Reefs Surrounded by Mysterious “Ghostly” Halos?

The study analyzes the spatial distribution patterns of “grazing halos” surrounding coral reefs. Around the world, coral reefs are often surrounded by noticeable bands of bare sand that appear clearly in satellite images, but the reason behind these patterns remains a mystery. One hypothesis is fear. Herbivorous fish like parrotfish leave the safety of the [...]

Satellite Images Reveal Creepy 'Halos' Around Reefs—Here's What They Really Mean

A new study published in The American Naturalist sheds light on the peculiar phenomenon of “grazing halos”—ghostly, vegetation-free rings surrounding coral reefs that are clearly visible in satellite imagery. These halos have long puzzled marine ecologists, who observed their consistent formation around patchy coral reefs across the globe. Although some theories suggested these patterns might be related to predator-prey interactions, this latest…