They look alike don't they, but which is which? Can you tell the difference between them? It's really quite simple.....or is it. Have you ever seen them together? They are both orange and black, have similar markings. But here's the thing they are very different....ya they look the same, but one is smaller, one has a horizontal line on the bottom wings, one is poisonous to most of their predators, or is it both, one lays her eggs on Milkweed and the larva eat the Milkweed, one lays her eggs on willow or poplar leaves and eats the willow and poplar leaves.
So whose who?
So let's compare the similarities between the two. Okay we know they both are orange and black and have white spots on the edges of their wings and what I didn't know until recently is that they are both poisonous to most bird species. Which I found quite interesting. But that's where the similarities end....that I know of. Notice that the Monarch has more white spots around it's head, the Monarch is also larger having between 3"to 4" wing span and male Monarchs have a black spot on the bottom wings. Now the Viceroy is smaller having a 2" to 3" wing span, and has the horizontal line on the bottom wings. The female Viceroy is larger than the males.
But it doesn't end there. The caterpillars of these 2 species though are different but similar. Ok the Monarch caterpillar is way cuter being that it's white, yellow and black striped, where the Viceroy is brown with a white spot. The idea with the Viceroy caterpillar is to look like a tree branch with a spot of bird poop a camaflage tactic and to top it off it is toxic, which again protects it from most predators. They get this toxin (Salicylic acid) from the Willow, Poplar and Cottonwood (also known as poplar trees) leaves they feed from. So the Monarch caterpillar being it's cuter (for a caterpillar that is) feeds on Milkweed. It too is toxic to most predators and it gets this toxin (cardenolide glycosides) from the Milkweed which like the Viceroy helps to protect once it leaves it's caterpillar life to become a butterfly.
Unfortunately for the Monarch Butterfly I have read and seen photos of a insect known as the Stink Bug and become immune the the Milkweeds poison and is eating the young larva and caterpillars of the Monarch which is causing havoc on the species.
So there you have it. My bit on the Monarch and the Viceroy butterflies. Both of which I have seen our meadow. There is so much more to learn about each of these butterflies, but maybe at a later time we can talk more about them.
In the mean time check your Willow, Poplar and Cottonwood trees for the Viceroy and check the Milkweed for the Monarchs.
Take a look at this neat Monarch Treasury. Lots of wonderful items for that Monarch Butterfly lover.