Pine processionary (Thaumetopoea pityocampa) caterpillars heading to bury themselves, Spain

procession thaumetopoea caterpillar heading spain pytiocampa europe los alcornocalles natural park insect larva horizontal following follow close together dependency lead leading led line row seeking brown black wild immature communal cooperation co operation jbr nobody outdoor animal spanish furry hairy sand high angle view sandy animal behaviour distinictive head to tail navigate navigating navigation thaumetopoea pityocampa thaumetapoea pupa pupae invertebrate insect pest jun08pgm s072