Viceroy

At first glance this may appear to be a photo of a monarch butterfly, however if you look closely you may notice a subtle difference. This is a viceroy butterfly. It is believed that they look like the monarch is a form of a defense mechanism. Because they eat the toxic milkweed plant as a caterpillar monarchs are either distasteful, at the least, or toxic to most predators. By looking similar to a monarch the viceroy may avoid encounters with predators that are wary of monarchs. The main way to tell the difference in the field is by size, the viceroy is noticeably smaller then the monarch, and the postmedian band that runs across the hindwing of the viceroy