Chemical trail marking and following by caterpillars of Malacosoma neustria

As in other species of Malacosoma , larvae deposit a trail pheromone when searching the host for food. Larvae in the vanguard of foraging columns establish chemical trails as they explore new territory. Marking behavior diminishes as successive unfed foragers utilize the trail. Other foragers follow the trails of fed larvae in preference to trails of unfed larvae. Thus, like the eastern tent caterpillar, M. americanum , successful foragers of M. neustria recruit colony-mates to feeding sites. The chemical activity of both recruitment and exploratory trails degrades slowly, suggesting that the trail pheromone of M. neustria is a nonvolatile substance. Caterpillars of M. neustria readily follow the nonvolatile trail pheromone which has been identified from M. americanum , 5 beta -cholestane-3,24-dione.