One of many insects that live on and eat from the Milkweed plant, the native Milkweed Tussock Moth spends its whole life around one species of vegetation. Like other Tiger Moths, the Milkweed Tussock Moth sports some bright, alarming colors like red, black, and orange. This gives a fair warning to would-be predators that the insect is not good to eat. The Milkweed plant sap that the moth feeds on contains a toxic chemical called cardenolide and it accumulates in the body of whatever eats it. Monarch butterflies, Milkweed Bugs, and this moth are prime examples of insects that benefit from this toxicity.
Adults are active from late spring to early autumn. Their wings are a drab gray color, but their bright yellow bodies are marked with rows of black spots on the sides. Females lay fertilized eggs in clusters on milkweed leaves. Newly hatched caterpillars begin as yellowish tubes with tiny black heads and are covered in white wispy hairs. They immediately begin chewing up milkweed leaves, leaving the veins behind. As caterpillars progress through their instars, colorful changes take over. The simple white hairs grow longer and the caterpillar gets covered in a mostly black coat. This is accented with bright orange-red hairs that almost form rings around each segment. Sets of long, white lashes stretch out from the head and rear. These hairs can cause skin irritation if the caterpillar is handled with bare hands. They are voracious eaters at every stage and can skeletonize a milkweed plant if decent numbers of them are present. Two broods can be produced in one year. It is common to see many caterpillars in the same area as they scout out places to pupate.
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* MAP NOTES: The territorial heat map above showcases (in red) the states and territories of North America where the Milkweed Tussock Moth may be found (but is not limited to). This sort of data is useful when attempting to see concentrations of particular species across the continent as well as revealing possible migratory patterns over a species' given lifespan. Some insects are naturally confined by environment, weather, mating habits, food resources and the like while others see widespread expansion across most, or all, of North America. States/Territories shown above are a general indicator of areas inhabited by the Milkweed Tussock Moth. Insects generally go where they please, typically driven by diet, environmental changes, and / or mating habits.