Week of October 5, 2025 – October 11, 2025
by Kaylen Iorio, Environmental Educator
Here at Baltimore Woods caterpillars become stars during the summer and fall. A very common caterpillar to spot is the Hickory Tussock moth caterpillar and students are fascinated to find them. These caterpillars are white and fluffy with black hairs running down their back but be careful if you touch one you might get a little itchy!
Hickory Tussock moth caterpillars, like many other caterpillars, have adaptations to protect them from predators. While these white fluffy caterpillars are easy to spot in the forest, their barbed hairs can attach to predators and cause an irritating reaction. Additionally, these caterpillars contain toxins within their body that make them hard to digest. The colors and patterns on Hickory Tussock moth caterpillar deter predators from eating them! What a cool defense mechanism! We see these adaptations in brightly colored animals like Monarch Butterflies and many other species. After overwintering in a cocoon, moths emerge colored tan with white markings on their wings, making excellent camouflage for life in the forest.
Io moth caterpillars are another unique find during the summer and fall. Discovering these caterpillars feels like you’ve entered a whimsical world of the forest. This bright green caterpillar has tiny tree-like structures on them that feel otherworldly, but, just like the Tussock moth caterpillar, it is best to observe them with your eyes only! When touched, their spines may attach to a predator, injecting irritants, another species with an incredible defense adaptation to deter predators from eating them! In their adult life stage Io moths can defend themselves by flashing large eye spots at predators, startling the attacker. These moths also rest amongst fallen leaves with perfect colors to match the subdue colors of the forest floor.
At each life stage both the Io moth and Hickory Tussock moth possess fascinating adaptations to deter predators and stay alive! What caterpillars have you seen lately?