Monarch Butterfly Poisonous. Migrations are long journeys in which animals are launched in search of food, heat. The Monarch is a common poisonous butterfly that eats poisonous milkweed in its larval stage But being poisonous doesn't help the Monarchs after a predator has already killed and tried to eat.

The concentration of cardiac glycosides decreases as individual butterflies age, and male monarchs have lower concentrations of toxins than females.
Some butterflies such as the Monarch and Pipevine Swallowtail eat poisonous plants as caterpillars and are poisonous themselves as adult butterflies.
Monarch butterflies do different things depending on when they complete their metamorphosis. Monarch butterflies cannot bite, and drink through a long tongue called a proboscis that works like The monarch butterfly's bright colors serve as a warning to predators that they are poisonous, and. The Monarch is a common poisonous butterfly that eats poisonous milkweed in its larval stage But being poisonous doesn't help the Monarchs after a predator has already killed and tried to eat.