The Mourning Cloak is a common butterfly of the Rocky Mountains with a unique winter survival strategy.
Mourning Cloak Butterflies are one of my favorites and a common Rocky Mountain butterfly. Here are 6 facts about the Mourning Cloak Butterfly.
My kids and I love finding butterflies when we are out exploring nature. I remember finding these butterflies on the trails when we went hiking and also around our house near Salt Lake City. One thing that always struck me was how ragged some of them looked. Well, it turns out they look ragged sometimes because they are old. Some of these spend the winter in their adult butterfly form.
6 Mourning Cloak Butterfly Facts
The Mourning Cloak is a relatively large butterfly with a 3 inch wingspan. Its wings are a dark brown color with cream around the tips of the wings and blue spots next to that.
This hardy butterfly has a unique strategy, as far as butterflies are concerned, for the cold Rocky Mountain winters. It survives winter as an adult butterfly, which is much different than most butterflies. Yes, rather than migrate to warmer areas or spend winter as an egg or larvae, it stays in its adult form. It takes shelter in a hole in a tree or under some bark and waits out the winter. Then in the spring it emerges and has a head start over the other butterflies for finding food and a mate.
During winter it enters a state of mild hibernation, called diapause. The adult butterfly takes shelter inside of holes in trees or under bark. This is not a permanent rest all winter long, but only a temporary one. You may see them flying around during warm, sunny days of winter.
The larvae of this butterfly prefer elm and willow trees and can most often be found near them. The caterpillars eat the leaves of these trees. As adults they eat some nectar, but their main source of food is tree sap. They can also obtain some nutrients from mud puddles and animal poop. Yep, you may have seen them near the mud next to a creek or river. I always wondered why they would gather there (they were getting nutrients from the mud!).
A ragged, tattered looking butterfly. Photo via Flickr.
The adult Mourning Cloak butterflies are among the longest living adult butterflies in the world. They can live for up to 10 months! A big reason for this is the fact that they remain in their adult form during the winter.
This is the state butterfly of Montana.
Other Butterfly Tips
Here is some fun information about these butterflies in the springtime.
Tell apart a butterfly and moth.
Don’t forget to check out the common butterflies of the Rocky Mountains.