Mourning Cloak is an attractive butterfly species belonging to the genus “Nymphalis”. It is felicitated as the State Insect of Montana. They are ardent fliers who love to hang out in locations far off from their usual territory.
Mourning Cloak butterflies are also known by several other names, such as
Camberwell Beauty (in Britain)
Picture 1 – Mourning Cloak
Caterpillars: The caterpillars can grow up to almost 2 inches long. They have a black body covered with sharp spines. On their backs, they have small red spots. The legs are maroon red in color.
Color: The upper surface of the butterfly has a purple brown or maroon coloration. A bright yellow color marks the edge of the wings which is bordered by several bright blue spots. The underside has a dark brown color with thin black lines.
Wingspan: These butterflies are quite large in size, with a wingspan of almost 6 to 10 centimeters.
Sexual Dimorphism: The females are somewhat larger in size than the males.
It is very interesting to observe the behavior of these butterflies. Learn about their most notable behavioral characteristics.
Mourning Cloaks like to feed mostly on tree sap and nectar.
They also aid in pollination of plants while visiting the flowers for nectar.
These butterflies have the habit of overwintering. They stay in their chosen spots throughout the year instead of moving southwards.
Mourning cloaks hibernate during the winter under some loose twig or in a tree cavity.
During the migratory season, they can be seen in almost any type of habitat.
Young larvae stay together in groups feeding on plant leaves until they reach their final instar or stage, when they choose to go their separate ways to form the chrysalis.
Mourning Cloak butterflies are abundantly found all over America from the Tundra region to central Mexico and Canada. They can also be seen frequently in Europe, Siberia, central Asia and Japan.
Picture 2 – Mourning Cloak Image
These butterflies love to roam around different locations. They look for trees or shrubs as host plants and can be found in various woods, gardens, parks, openings, suburbs and riparian areas.
Mourning Cloak caterpillars feed on the leaves of various trees and shrubs, like the willow (Salix spp.), cottonwood (Populus spp.), elm (Ulmus spp.), paper birch (Betula papyrifera) and hackberry (Celtis spp.). They are quite fond of scabiosa and knapweed flowers.
The adults often drink the nectar from some plants like Red Maple and Milkweed but they mostly sustain themselves by consuming tree sap and decaying fruits. They can also obtain essential nutrients from mud puddles and animal droppings.
These butterflies choose certain specific plants as their hosts, namely, the American elm, Black willow, hackberry, poplar, hawthorns and wild rose.
These butterflies fly with a flap-glide motion.
Some of the adult butterflies migrate towards the south during the fall season, while others choose to stay behind.
Picture 3 – Mourning Cloak Butterfly Image
These butterflies are hunted by insect eating animals, birds, reptiles, amphibians and other insects such as ants, beetle larvae, beetles, mites, bugs, dragonflies, assassin bugs, spiders and praying mantises. The butterfly eggs and larvae may get destroyed by wasps and flies who may lay their eggs on them.
These butterflies evade their predators by using certain special means. Such adaptations have been discussed below:
The body of the Mourning Cloak caterpillars is covered by sharp spines which helps them to avoid predation.
The caterpillars also have two red spots which are known as ‘false eye spots’. These spots help in distracting the predators by grabbing their attention to a less vulnerable area.
Adult butterflies can camouflage themselves by adapting their body color to the color of the tree trunk in the background.
Reproduction and Life Cycle
These butterflies mate in early spring season, soon after they emerge from hibernation. The males normally select a sunbathed spot as their nest. After a brief courtship ritual in air, the female lays around 30 to 50 eggs in clusters on the branches of the host tree. At first, the eggs are pale yellow in color, which turns to red and eventually becomes black before hatching.
Small, black caterpillars emerge after the eggs are hatched. The caterpillars have white spots on their bodies and a dark, continuous line on the dorsal side.
The newborn caterpillars eat voraciously, consuming the leaves of trees such as willow and elms. The caterpillars grow quickly while experiencing the four molts. They pass through their larval stages and reach the inactive pupal phase. The pupa is enclosed in a gray silk chrysalis which hangs from the branches of the host tree. The adult butterfly comes out of the chrysalis after about 15 days.
Picture 4 – Mourning Cloak Caterpillar
The average lifespan of this species of butterfly is about 10 months.
Caring for the Mourning Cloak is rather easy and it is good fun to see the larvae and caterpillar going through the different stages of their life cycle.
Housing: Get a medium to small sized aquarium to house these butterflies. You can also use a net enclosed container or a screened cage. Adorn their home with the host plant Black willow or American elm and place the larvae or caterpillar on it. The plant should be free of any pesticides or harmful chemicals. If it is not so, wash the plants well with water before placing it in the cage.
Feeding: The caterpillar will consume the leaves of the host plant. An adult butterfly will feed on plant sap, nectar and rotting fruits.
Caring: The plant provided for the Mourning Cloak caterpillar should have enough hanging area from where it can hang itself. This is important for the proper growth of the caterpillar into a healthy butterfly.
Mourning cloaks are abundantly found in their natural habitat zones and as a result it is not considered to be an endangered species.
Here are some interesting facts about these butterflies.
Mourning Cloak is the State Insect of Montana.
An unusual trait of these butterflies is that they go through an aestivation phase during summer and hibernate during winter.
The Mourning Cloak eggs are yellow at first but they change their color gradually to red and finally black prior to hatching.
They make a loud clicking noise before flying away from a place of rest.
Mourning Cloak caterpillars are sometimes referred to as spiny elm caterpillar.
Here are some pictures of these beautiful butterflies.
I saw one this morning, 03-09-12, in Colorado. It flew around my backyard and landed on some leaves, I got to get a good look at it, it also flew right by my face. My question is why are they called Mourning Cloak?
We have them flying all over the garden suddenly and we are in Ontario Canada. I imagine they are called that due to their dark colours resembling a cloak or coat that would be worn at a funeral.
I spoted a montana state mourning cloak butterfly in the state of Connecticut. July 28 2014
A mourning cloak butterfly seen in my garden this Spring when patches of snow were still on the ground.
A black swallowtail sat on my cone flower on September 1st.