Milkweed Tussock Moth Caterpillar (Euchaetes egle). This caterpillar just might alarm you if you’re growing milkweed with Monarch Butterflies in mind. No need to worry though. The Milkweed Tussock Moth and the Monarch Butterfly have grown up in the “same neighborhood” side by side, sharing the bounty. Both butterfly and moth caterpillars are eating a poison contained in the milkweed called cardiac glycosides (cardenolides) to provide protection, making both creatures distasteful to birds and bats. As adult moths, the Milkweed Tussock Moth is able to communicate with bats emitting an ultrasonic click which bats take as a warning to stay away. Mighty clever.

Those of us who are growing milkweed to help the plight of the Monarch Butterfly might consider that the Milkweed Tussock Moth would appreciate our help as well. The photo above gives you a glimpse of Milkweed Tussock Moth Caterpillars in various stages of development. Let them dine at the milkweed plants with the Monarchs!