Under a moon spell: Shark attacks related to lunar phases. New research suggests that more shark attacks occur during fuller phases of the moon. While the exact cause remains unclear, the researchers found that more shark attacks than average occur during periods of higher lunar illumination and fewer attacks than average occur during periods of lower illumination. Many different types of animals show behaviors that are linked to moon phases yet few studies to date have looked at the connections between lunar phases and shark attacks. Source 6y.