Monarch Butterflies are a well known butterfly due to their amazing migration. Here are some more facts about these cool Rocky Mountain animals.
I remember first hearing about the Monarch Butterflies when I attended University of California at Santa Barbara. Some other people mentioned once that they were going to take a bike ride and look for the monarch butterflies. I had no idea what they were talking about, but joined them. We found thousands of them overwintering in some trees and it was cool.
Here are the Monarch overwintering just north of Santa Barbara. Photo via Flickr.
9 Monarch Butterflies Facts
They are most well known for their magnificent migration from winters in southern California and Mexico. Then several generations of adults travel as far north as the Canadian Rockies.
This is North America’s most famous butterfly both for its migration and because it is so widespread.
Adults lay eggs in milkweed. When the eggs hatch the larva eat the milkweed, which contains toxic substances. The Monarch larva and then adult keeps the toxic substance in their body, which makes them taste bad and toxic to birds and mammals. Thus, this animal has developed a great strategy whereby it is able to eat a plant that is toxic, which protects it from being eaten by its predators. Read more about the butterfly lifecycle here.
The Monarch caterpillar is a big eater.
Similar to all insects, the Monarch undergoes metamorphosis in which it changes from a larva to an adult. However, the larva form actually molts its skin 5 times before it goes into a pupa and becomes an adult.
As a caterpillar the Monarch eats a lot! In fact, the caterpillar grows many times its original size. The eggs are super tiny – about the size of a pinhead and the final stage of caterpillar is about 25 – 45 mm.
It takes a Monarch about one month to grow from an egg to a mature adult.
As adults the Monarch butterflies live about 2 to 6 weeks during the summer.
The final adults that are born in late summer or early fall have the important job of migrating back to their wintering area in California or Mexico. These adults make the long journey and live for between 6 and 9 months.
A male has the black spots on its wings.
Adult male and females may look similar at first glance. But, a closer inspection will allow you to easily tell them apart. The male has a black spot on one of the veins on the lower part of its wings. Also, females are usually a bit darker and have wider veins than the males on their wings.