Woodlice in Death Spiral Under Streetlights

Streetlights in Northern Israel's Golan Heights and Jezreel Valley have been linked to a peculiar phenomenon affecting woodlice. Thousands of these small invertebrates, specifically Armadillidium sordidum, have been observed forming massive circular patterns, a behavior scientists are calling a 'death spiral.'

This collective mass movement, documented in videos captured between 2021 and 2025, occurs exclusively at night under artificial lighting. While collective animal movements often serve a purpose, such as migration for resources, the woodlice's circling appears to lack direction or benefit. Researchers hypothesize that the artificial light source disorients the woodlice, drawing them into these self-sustaining, yet detrimental, formations.

The ecological implications are significant, as this disruption interferes with natural behaviors like feeding and mating. Furthermore, the concentrated aggregations may attract predators, like the observed centipede preying on the woodlice. This phenomenon highlights the growing evidence of artificial light's negative impact on wildlife, from ground-dwelling arthropods to nocturnal amphibians and migrating birds.