The monarch butterfly is an iconic North American insect known for its striking appearance and incredible migration journey. With bright orange wings outlined in black and adorned with white spots, it’s a visual marvel that has captured the interest of researchers, students, and butterfly enthusiasts alike.
One fascinating aspect of the monarch butterfly is its unique two-way migration, similar to what birds do. Unlike other butterflies that can overwinter in various life stages, monarchs are unable to withstand the harsh winters of northern climates. These environmental cues signal the butterflies to travel south, ensuring their survival during the colder months.
Throughout their lifecycle, monarch butterflies rely on specific plants and environmental factors. One primary resource for these insects is milkweed, which serves as a crucial food source for monarch caterpillars. As adults, these butterflies feed on the nectar of various flowering plants, making them important pollinators in ecosystems where they reside.
Monarch Butterfly Basics
Monarch butterflies are easily recognizable due to their vibrant orange wings with black veins and a border of white dots. Their wingspan typically ranges from 3.7 to 4.1 inches, making them a large and noticeable insect. Some key features of adult monarch butterflies include:
- Bright orange wings
- Black border with double row of white spots
- Black veins covering the wings
Males and females have slight differences, with males having narrower wing venation and scent patches. The bright coloring of a monarch serves as a warning to predators that they are unpalatable, which helps in their survival.
The monarch butterfly, scientifically known as Danaus plexippus, belongs to the family Nymphalidae. They are one of the most famous and studied butterflies in North America and are known for their incredible two-way migration pattern.
Here’s a comparison table of Monarch and Viceroy butterflies:
|Monarch Butterfly||Viceroy Butterfly|
|Danaus plexippus||Limenitis archippus|
|No line on hindwing||Line present across hindwing|
|Distinct scent patches (males)||Absence of scent patches|
|Larger size||Smaller size|
These two species might look very similar, but upon closer observation, the differences become evident, mainly the line across the hind wing of the Viceroy butterfly.
Life Cycle and Metamorphosis
Monarch butterflies lay their eggs on milkweed plants, specifically on the leaves. The eggs are small and white, and a female Monarch can lay from 100 to 300 eggs during her life. They take about four days to hatch.
Once the eggs hatch, caterpillars emerge, and their main food source is the milkweed leaves. Caterpillar characteristics include:
- Less than 1 cm in size upon hatching
- Grow to be about 5 cm in size
- Possess tentacles
Monarch caterpillars go through multiple instars or stages, with each molt resulting in a larger and more developed caterpillar. This process takes about two weeks.
- Caterpillars feed on milkweed plants, primarily on the leaves
- Milkweed plants provide necessary nutrients for healthy growth
Comparison Table: Milkweed vs. Other Leaves
|Milkweed Leaves||Other Leaves|
|Caterpillar Growth||Supported||Not Supported|
After reaching their full size, the caterpillars enter the chrysalis stage, where they undergo metamorphosis. They remain in this stage for approximately five days before emerging as adults.
The final stage in the monarch butterfly’s life cycle is the adult stage. Here, they begin feeding on nectar from various flowers and start the breeding process. Adult monarch butterflies can be identified by their distinctive orange and black patterned wings.
- Male and female monarchs mate in their wintering grounds
- They migrate to various parts of North America to lay their eggs
Eastern and Western Populations
Monarch butterflies are split into two distinct populations: the Eastern population and the Western population. The Eastern population, residing in the United States and Canada, consists of the majority of Monarch butterflies, while the Western population is found predominantly in the western United States.
- Eastern monarchs: Travel to central Mexico for winter
- Western monarchs: Overwinter in coastal California
- Eastern route: Northeastern United States and Canada to central Mexico
- Western route: Western United States to coastal California
The Rocky Mountains play a significant role in the migration patterns of the Western population. These butterflies utilize the mountain range as a natural divide, assisting them in their journey to California.
- Monarchs use the Rockies as navigational reference
- Helps guide Western population to coastal California
Habitat and Environmental Factors
Monarch butterflies require specific habitats to support their life cycles. They particularly depend on milkweed plants (Asclepias), as these are the only plants where females lay eggs and caterpillars feed. Monarchs can be found in areas with a variety of milkweed types like fields, roadsides, wet areas, and even urban gardens. The right habitat should have:
- Different milkweed species
- Nectar sources for adult butterflies
Besides milkweed, adult monarchs also feed on the nectar of numerous flowering plants. Some examples of nectar sources for monarchs include:
By providing diverse nectar plants, a suitable habitat supports the population and aids in their migration.
Human activities have significantly influenced monarch populations. Habitat loss due to urbanization, agriculture, and herbicides has restricted their breeding areas. The use of pesticides can also harm monarchs by:
- Directly affecting their life stages
- Eliminating milkweeds and nectar plants
Conservation efforts are essential to protect monarch butterflies and their habitats. A combination of practices can help, such as:
- Planting native milkweeds, especially for breeding and pupation
- Incorporating nectar flowers in gardens or landscapes
- Reducing the use of pesticides and herbicides
- Supporting habitat restoration projects
- Contributing to citizen science projects tracking monarch populations
In summary, monarch butterflies rely on specific habitats, nectar sources, and environmental factors for their survival. Human impact has led to threats, but conservation efforts can help protect these vital pollinators.
Threats and Conservation Efforts
Endangered Species Status
The monarch butterfly is facing endangerment due to habitat loss and other factors. Efforts like the North American Monarch Conservation Plan aim to protect its unique migratory phenomenon.
Climate Change Impact
Climate change affects monarchs by altering their habitat and disrupting migration patterns. Conservation measures are necessary to mitigate these impacts.
Citizen Science Initiatives
Citizen science plays a vital role in monarch conservation, through initiatives like the Monarch Joint Venture.
|Aspect||Endangered Species Status||Climate Change Impact||Citizen Science Initiatives|
|Main Focus||Habitat protection||Migration & habitat||Community involvement|
|Key Organizations||NAMCP||Government agencies||Monarch Joint Venture|
|Examples of efforts||Conservation plans||Climate actions||Monitoring programs|
Features of monarch conservation efforts:
- Habitat restoration
- Local community engagement
- Monitoring population trends
Characteristics of successful conservation initiatives:
- Collaboration with multiple stakeholders
- Public education and awareness campaigns
- Long-term implementation plans
Pros and cons of various conservation methods:
- Habitat protection:
- Pros: Directly addresses the main threat
- Cons: Requires ongoing monitoring
- Climate change mitigation:
- Pros: Addresses multiple species’ needs
- Cons: May be slower to see results
- Citizen science initiatives:
- Pros: Enhances public engagement
- Cons: May require significant resources for data management
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – Monarch
Subject: First Monarch of the Year
Geographic location of the bug: West LosAngeles
Time: 02:34 PM EDT
Your letter to the bugman: Hi Bugman,
Found this guy probably a short while after he emerged. What a beauty.
How you want your letter signed: Jeff Bremer
This is a beautiful male Monarch, and we agree that he is most likely newly emerged from the chrysalis. We have seen a few female Monarch butterflies this year nectaring from the Lantana.
Letter 2 – Monarch Butterflies Mating
The two monarchs on this photo were one pair of about six in the area. The pairs would fly about with one butterfly on top doing the flying and the one underneath just hanging on, legs to legs and tail to tail. Every once in awhile they would alight on a branch, freeing their legs up just before landing and end up with just the tails touching. When they resumed their flight, the bottom butterfly would reach up to re-establish the grip on the legs. I guess having one butterfly carry the other while flying is a good test to see if the partner is suitable mating material considering the migration to Mexico they have to undertake in the fall. Regards
We like your theory about flight strength and migration, but other butterflies that stay local use the same position. Thanks for sending us your wonderful image.
Letter 3 – Monarch Butterflies raised in captivity
11 Monarchs in a row
Location: Naperville, IL
July 1, 2011 12:16 pm
I wanted to show you this photo for the sheer fun of it. I raise Monarch butterflies each summer – mainly by collecting the eggs that female Monarchs lay on the milkweed I grow in my own yard. Last summer, we released over 200 butterflies with a very small mortality/sickness rate – about 5%. On the days that we have butterflies eclose, I like to pose them for photos on flora around my yard. They will typically ”hang out” for a few hours after drying their wings, allowing me to get some fun shots. One day last summer (July 2010), we had 11 adults eclose on the same morning, and knowing that I couldn’t possibly place them all on one flower, we got the idea to place them on a string tied between two chairs. (We do this anyway on the odd occasion that a newly-eclosed butterfly loses grip on its chrysalis and falls). Eventually, of course, they all flew away, but they remained on the line like this for quite a while. My condolences on the p assing of Lefty. Best regards,
Signature: Dori Eldridge
Hi again Dori,
Thanks so much for sending this charming documentation.
Letter 4 – Monarch Butterflies Roost at Pismo Beach
Location: Pismo Beach, California
January 26, 2011
I continue to thoroughly enjoy your site — especially here in central Minnesota in January.
In November, my family and I learned the monarch butterflies west of the Rockies spend their winters in coastal California. We’ve wanted to visit the sites “our” monarchs use in Mexico, but that’s very expensive and currently too dangerous. I know yours is not a travel site, but we learned of this place quite by accident, and I’m sure other bug nuts would appreciate learning about Pismo State Beach, and the other sites there. Perhaps you need to add a “travel section” to WTB.
I could tell you much more about our trip to your state. Beyond seeing thousands of monarchs, it was very interesting to see how many of the butterflies there are tagged. We observed four or five different-colored circular tags, and many butterflies marked by coloring in a cell on the rear right wing with a Sharpee marker. This is done by those keeping track of the number of butterflies using the site (around 20,000).
Anyway, the Pismo site is very accessible to anyone and easy to find. The butterflies are there from November through February, depending on the weather.
You can learn more at: http://www.monarchbutterfly.org/
Thanks for your continuing excellent work.
Don J. Dinndorf
St. Augusta, MN
Thanks for your wonderful letter. It is interesting that these Monarchs are roosting in a eucalyptus tree which is not native to California. Though I have never visited one of the roosting sites, I did have the distinct pleasure of seeing migrating Monarchs roosting in a tree in Roosevelt Park in Youngstown, Ohio as a child. It was an awesome sight.
Hello again, Daniel. Thanks for your quick reply.
A graduate student studying the Pismo monarchs told us the monarch used to roost in cyprus trees there. But the pioneers cut those trees down, and planted eucalyptus. The “new” trees leaves are glossy, and she told us the butterflies have a hard time getting a grip, sometimes falling right off. The State Park is trying to re-establish some cyprus there.
Interestingly, the grad student also said when they are counting the butterlfies, they have to double their estimate for those clusters on the cyprus, because the monarchs group so much more tightly on their original tree species.
Letter 5 – Monarch Butterflies: Rough Sex
Hello Bug Man!
We love your site in this house! While at the shore each year I enjoy photographing butterflies. I am attaching several photos of two butterflies that appeared to be wrestling on the ground. This went on for a few minutes with the two ultimately flying off in different directions. I have never seen such aggressive behavior. Is it associated with mating? Any help appreciated. Thank you in advance.
This is a pair of Monarch Butterflies. A mating pair will stay engaged for a lengthy period of time. Perhaps what you witnessed was a difficult “uncoupling”.
Letter 6 – Monarch Butterfly
Monarch Butterfly with wings fully spread
Since my Geneva, Illinois garden is quite dead at this time of year, I enjoy going to your website to view all of the beautiful garden visitors from around the world. I noticed, that although you have many pictures of Monarch butterflies on your site, you don’t have a good picture of one with its wings fully spread. This past summer I was finally able to get a shot of a Monarch in full wing spread, and thought you might like a copy for your files. Thanks,
Thanks for your wonderful photo, a welcome addition to our archives. As you realize, now that winter is upon us, many of our recent postings are from Australia. We have two Australian Hemipterans to post from yesterday, but we couldn’t resist your kind letter and beautiful photo of a male Monarch Butterfly.
I’m glad that you like the picture. It was not easy to obtain. Monarchs do not keep their wings spread for very long — not more than a few seconds. I had to use the sports mode on my camera, which takes numerous pictures in rapid succession. It took many monarch visits, and hundreds of shutter clicks to get the perfect shot. I am happy that I was able to contribute to your great site. Thanks,
Letter 7 – Monarch Butterfly
Butterfly And The Pink
Location: Raleigh, North Carolina
July 24, 2010 9:44 am
I would guess this is a monarch, but I am not sure.
Thank you for your help 🙂
Your identification of the Monarch Butterfly is correct. There appears to be an odd filter used on your photograph that give the tonalities a postarized effect. We do not like to use photographs on our site that have exaggerated post production digital special effects, but since we don’t have many images of Monarch Butterflies, we are making an exception since most of the postarization is in the background and not in the Monarch itself. We also noticed that you sent us numerous emails this morning. We will probably not be able to answer all of them, but we will give it a shot.
Thank you for your response. I do apologize for all of the numerous emails. I lost what Info I had off my old site, and I am trying to build the new site better and including more ID and credit to others
That photo might have the posterized look to it. I will see if I can find the original as I sort and send the original to you. I had forgotten that one did.
Thank you for your time and willingness for any help. It is appreciated more than you could imagine!
There is no need to send another photo. We just like informing our readership that they shouldn’t creatively alter the images too much in the interest of correct documentation.
Thank you! You have really made my day! 🙂
Letter 8 – Monarch Butterfly
Location: South Jersey
October 12, 2010 8:04 am
Just wanted to make sure this is the type of butterfly I think it is.
The Monarch butterfly is arguably the world’s best known butterfly, and it has been popularized because of its yearly migrations to warmer regions in Mexico, Florida and California when winter approaches. The Monarch Butterflies in Big Sur website has a nice migration map, and people wanting to track the migrations can visit the Monarch Journey South News website.
Letter 9 – Monarch Butterfly
Subject: Monarch Butterfly Fort Lauderdale
Location: Fort Lauderdale, Florida
July 19, 2012 9:45 pm
Just thought I’d share a lovely picture of a Monarch Butterfly I took in my backyard in Fort Lauderdale, FL.
I hope you enjoy!
Thank you for sending a photo of a Monarch Butterfly. It is a very nice addition to our site. Mike from Kansas recently wrote to us that he has not found any Monarch Caterpillars this year. A recent article in the LA Times indicates that “California’s Monarch population has fallen an estimated 80% over the last 15 years due to urbanization, drought, weed abatement programs and pesticides said Scott Black, executive director of the nonprofit Xerces Society, a Portland, Ore.-based organization dedicated to the preservation of invertebrates.”
Letter 10 – Monarch Butterfly Caterpillar
Please help to identify
I took these photos about 11 AM today 9/10/05 in bright sunshine. I was in Central Park, New York City, USA. The caterpillar was on a leaf. The plant may be a milk weed. Would appreciate any help.
We are thrilled to find out that Monarch Butterflies are reproducing in NYC.
Letter 11 – Monarch Butterfly Caterpillars
Location: Charelston sc
November 10, 2011 9:22 pm
My friend, an elementary school teacher in Charleston, SC, took these photos on November 10.
Signature: The non-entomolgocial biologst, Alex Hartman (University of South Carolina)
The plant in the photo appears to be an exotic milkweed, and they are usually promoted as butterfly plants. The caterpillars in the photo are Monarch Caterpillars and they will metamorphose into Monarch Butterflies. The caterpillars of Monarchs feed on milkweed.
Letter 12 – Monarch Butterfly Chrysalis
My daughter found this hanging on our fence. The dots are gold. It’s beautiful. Any clue what’s inside? Thanks.
This is a Monarch Butterfly Chrysalis. It will turn tranparent and reveal the orange wings just before the butterfly emerges.
Letter 13 – Monarch Butterfly deposits egg on Milkweed
Monarch Butterfly Ovipositing on Mexican Milkweed
Location: Hawthorne, CA
October 11, 2011
Here are my Monarch photos. I’m thinking that I definitely had ovipositing going on in the photos that contain Mexican Milkweed?
Thanks for sending us more photos of the thriving Monarch Butterfly population in your home garden Anna.
Letter 14 – Monarch Butterfly, just emerged from chrysalis
follow up to cocoon picture
I just got a moment to follow up with this picture of my monarch hatching. I thought you might want to see it. Also, tell Lisa to watch for her box of chocolates. We sent out some chocolate butterflies.
Olde Naples Chocolate
Thanks for the follow-up on your Monarch Chrysalis. We know Lisa will be waiting eagerly for her chocolates.
Letter 15 – Monarch Butterfly: The Wanderer found onboard ship in Brazil
I came across your website whilst trying to identify these moths, my husband is currently working aboard a ship in Brazil and these little guys hitched a ride!
From the info you have on the site I think I am right in saying that possibly 3 of the moths are the Black Witch even though they vary in colour a little bit..?? I have no idea about the rest but they are all big moths from 6 – 8 inches across. Best wishes from
Elaine in Northumberland, UK.
All but one of your images are of moths. The image labeled Moth 6 is actually a Monarch Butterfly, justifiably known as The Wanderer. We agree that several images appear to be Black Witches or closely related species. Moths 4 and 5 are two different species of Sphinx Moths.
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – Bug of the Month August 2022: Monarch Butterfly
Subject: Male Monarch Butterfly visits wildflowers in the garden
Geographic location of the bug: Campbell, Ohio
Time: 11:08 AM EDT
There are some changes happening to What’s That Bug? including Daniel finally relinquishing some of his megalomaniacal editorial control by allowing a staff to take over much of the incoming mail for identification requests because over the years Daniel has only been able to respond to a small percentage of the voluminous number of emails that pour in daily.
Daniel can now spend more time on focused postings that address the interconnectivity of all things on our fragile planet, always the mission of our ecologically minded web site.
Recently Daniel noticed an attractive pickup truck pulling a tractor parked across the street. The truck was white and advertised “Lawn Care” and graphics of Monarch Butterflies were flying over a homogeneously green lawn. Upon speaking to the driver, Daniel learned that the neighbor’s perfectly manicured lawn was about to be sprayed with herbicide to control the weeds and fertilizer to encourage the growth of that perfect lawn. So just why were the Monarch Butterflies on the truck?
Daniel can only surmise that the Monarchs are there to alleviate the anxieties of any potential customers who worry about the negative effects of the chemicals because clearly they are not only harmless to butterflies, but their use might even encourage butterflies to flit about on the grass.
A bit of internet research revealed that painting Monarchs on lawn care trucks is not a new idea as this web page entitled To Pimp a Butterfly illustrates.
If you want to attract Monarch Butterflies to your garden and to aid their declining populations, Daniel would strongly urge you to cease and desist using herbicides in the yard, to plant milkweed as is being promoted in many circles, but to also plant additional wildflowers that will provide nectar for the butterflies. Milkweed is an excellent plant for providing nectar, but butterflies, including Monarchs, do not limit themselves to taking nectar from a single type of plant. Monarch Caterpillars are not that indiscriminate. Monarch Caterpillars feed solely on milkweed, and growing milkweed is necessary if you want the Monarchs that visit to also reproduce in your garden. There are many wildflowers that can be planted to attract Monarchs and other butterflies, and Joe Pye Weed and Bull Thistle are two of the best. Happy Butterfly viewing.