Pine Processionary Caterpillar Caravan
These are pine processionary caterpillars (Thaumetopoea pityocampa). They form processions like this when they are in search of pupation sites. Laughing Squid reports that this particular procession, filmed by Sweden-based Mehmedsamirs is nearly 13 feet long. The procession may help the caterpillar defend itself from predators by fooling them into thinking it is a snake. These caterpillars also have another defensive feature: barbed hairs that can cause skin rashes. They are considered a pest in eastern Europe.
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