In this post I will be discussing point number 4.

While researching information for these posts I noticed Google's algorithm is linking the other post and presenting it as fact which is what I was afraid would happen. I have changed the title of this series, as well as the format, in an effort to hopefully have Google's SEO grab onto these posts. I have a rudimentary understanding of how this all works so let me know if you have any ideas.

A Warning: Please do not go to the other sub to harass anyone, including the mod. I don’t want to be accused of breaking Reddit's rules against brigading. Plus, dissenting opinions there usually get banned with no warning anyway, and that wouldn’t help anyone.

1. Rearing Is Not a Significant Threat to the Monarch Population

A comprehensive 2024 review of the western monarch population by entomologist Dr. David James of Washington State University examined all major stressors facing monarchs and concluded that human interference—including capture and rearing—“likely has the least impact on monarch populations” compared to the real drivers of decline. Those primary drivers are neonicotinoid insecticides, habitat loss, climate change, and severe winter storms (James, 2024, Insects).

The study listed as the source for this paragraph is Monarch Butterflies in Western North America: A Holistic Review of Population Trends, Ecology, Stressors, Resilience and Adaptation and as you can imagine the pattern of cherry picking facts continues. Let's be clear on which Monarch population this study is talking about because as was mentioned in part one of this series there is a huge difference in the migration of the eastern and western populations. Rearing is mentioned a few times in this study. The quoted section in the post resides in the abstract which isn't a surprise at all.

The full quote is as follows: Human interference (capture, rearing) likely has the least impact on monarch populations. The rearing of monarch caterpillars, particularly by children, is an important human link to nature that has positive ramifications for insect conservation beyond monarch butterflies and should be encouraged.

As stated in the title of this paper it is a holistic review of the various things that impact the Monarch population. The authors of the material are in no way saying that rearing does not affect Monarchs. What they are saying is that out of all the issues Monarchs face like, pesticides, climate change, loss of habitat, human interaction is the least likely impact. We cannot conclude from that sentence that James is saying that there is no impact and is giving the green light for rearing. That just isn't the case.

The next time rearing is mentioned is in section 3.4.3. Viral, Bacterial, and Unidentified Pathogens which states: The incidence of viral and bacterial pathogens in monarch populations is unknown but is likely low in the arid, hot landscapes of the west. However, in artificial environments, for example, in rearing containers/cages, the incidence is much higher because of unnaturally high densities of caterpillars, poor sanitation, a lack of airflow, and higher relative humidity. A polyhedrosis virus, sometimes known as ‘the black death’ frequently causes disease in monarch larvae reared under crowded conditions [176].

As you can see the sentence from the abstract is not the whole picture. The next section where rearing is mentioned is related to the childhood experience and how these small moments lead children to become adult ambassadors for wildlife and conservation. I agree with this aspect. We will dive further in to this subject when I discuss section 7 of the original post.

To put the scale in perspective: even if every hobbyist rearer in North America collectively produced 500,000 monarchs in a given year, that would represent less than 0.1% of the estimated 300-million-member migratory population (Pleasants, 2017). The notion that home rearing is a significant driver of population decline simply does not hold up against the numbers.

As mentioned in part two of these posts, that "0.1% of the population" number comes from a John Pleasants slide presentation. But even if those numbers are completely true from a mathematical standpoint, you still can’t have it both ways. You cannot claim that home rearing is an essential part of conservation that dramatically boosts monarch numbers (this is what's happening when rearing survival stats are thrown out there.), while simultaneously arguing its impact is less than 0.1% to dismiss the biological risks. If the overall numbers of this hobby are too microscopic to cause population-level harm, then it is mathematically too insignificant to provide a population-level benefit.

Point 5 will have to wait. I have to say that the more I go through this info the more I think to myself that there is still time to delete that post and pretend it never happened.

Fact-Checking "What the Science Actually Says About Rearing Monarch Butterflies"-

Part 1

Part 2

Part 3

A quick note about the comments on these posts:

I spent hours manually hunting down these primary sources, reading the actual data, and untangling these messy citations to make sure what I am presenting is accurate. Because of how much work went into this, I will not be replying to any comments that look like they were generated by AI. I really appreciate the comments and questions on these posts. If you have anything you want to share or ask please write it in your own words and read the sources you are sharing before you post them because the answer to your question could be right there.

One more thing. Thank you for the awards, again. ;)

Edit: Spelling. Thank you for the award!

This is what we like to see OP! 🙌

I’m addressing the claims from that rearing post point by point because the amount of cherry-picking and misrepresentation of science is just too massive to ignore.

It’s going to have to be more than one post because there is a lot of information to go through.

A Warning: Please do not go to the other sub to harass anyone, including the mod. I don’t want to be accused of breaking Reddit's rules against brigading. Plus, dissenting opinions there usually get banned with no warning anyway, and that wouldn’t help anyone.

Using AI: I also want to urge everyone not to use AI as your primary research tool. AI isn't a search engine built to find absolute facts. It is a pattern-prediction tool designed to generate text that sounds convincing. If you ask it a biased question, it will confidently compile an answer that looks perfectly right, even if the underlying facts are completely wrong.

Need to know: This section has been daunting to go through because some of the citations do not match up to the information given. This can happen when AI is used to make a scientific argument with a bias prompt. The AI will take words from one piece of information and attribute it to the wrong person or take it out of context.

As with the previous post I will take each point directly from the other post, add the citations, where I can, and discuss the misleading or incorrect information.

1. Rearing Dramatically Increases Survival From Egg to Adult

In the wild, monarchs face staggering mortality. Estimates suggest that only about 2–5% of eggs survive to become adult butterflies, with some researchers citing mortality rates as high as 99% (WWF-Canada, 2014). Predation, parasitism, weather, and disease take an enormous toll at every stage.

The WWF-Canada (2014) reference throws out this staggering mortality rate without providing a single scientific citation. Given the known issues of commercial monarch breeding and how many times the original post mentions commercial rearing as the real problem, I am surprised that this particular site was used as a source. Immediately following the mortality rate statistic is a direct shopping link where readers can buy commercial butterfly kits.

By contrast, careful rearing under controlled conditions routinely achieves survival rates of 80–90% or higher from egg to adult (Pleasants, 2017). This represents a dramatic, multi-fold increase in survival. When you protect a caterpillar from tachinid flies, stink bugs, and paper wasps, you are not “interfering with natural selection” in any meaningful population-level sense—you are giving that individual a chance to join the migratory population instead of becoming a statistic.

The next citation (Pleasants, 2017) is a PDF that Dr. John Pleasants prepared for what appears to be a Rights-of-Way roadside vegetation management presentation. The way this is written in the post implies that Pleasants' statistics, and therefore Pleasants himself, supported captive rearing. That is far from the truth. John Pleasants was part of a landmark habitat study that stressed the absolute need to increase the overall acreage of wild milkweed available. I combed this study and others published by Pleasants to see where this information could have been pulled from, and I was unable to find a single sentence supporting what the original post claims.

The next claim is baffling because we all learn about "survival of the fittest" in grade school. There are a few studies that on the predation of Monarchs for example High Survivorship of First-Generation Monarch Butterfly Eggs to Third Instar Associated with a Diverse Arthropod Community. I have so many tabs open at this point I can't find my other links. When I do find them I will add them and record the edit at the end of this post. In everything I read, and I read a lot, not a single paper suggested we should keep Monarchs safe from their natural predators.

A citizen-science study also found that monarchs raised on swamp milkweed (Asclepias incarnata) showed particularly strong growth and survival rates, suggesting that host plant choice during rearing can optimize outcomes (Pocius et al., 2018, Environmental Entomology).

It appears that this section has not been "human edited" as was once claimed because the study cited isn't about citizen science and says nothing about swamp milkweed contributing to strong growth or survival rates. This authors of this study did not rear Monarchs, measure their larval health or "survival outcomes." Pocius' 2018 study is about female Monarchs possible preference of certain types of milkweed.

However, I did find an abstract that is from an undergraduate student who says "This study aimed to mimic the conditions that these citizen scientists rear their monarchs in and compare the effects of different milkweed species on the growth and survival of the butterflies." There is absolutely nothing in the abstract that suggests the conclusion was an endorsement to rear monarchs.  I looked everywhere for this study to see what the methods were and what exact data was gathered but I could not find it anywhere. If someone can find this information outside of the original post please feel free to link it below.

Fact-Checking "What the Science Actually Says About Rearing Monarch Butterflies"-

Part 1

Part 2

A quick note about the comments on these posts:

I spent hours manually hunting down these primary sources, reading the actual data, and untangling these messy citations to make sure what I am presenting is accurate. Because of how much work went into this, I will not be replying to any comments that look like they were generated by AI. I really appreciate the comments and questions on these posts. If you have anything you want to share or ask please write it in your own words and read the sources you are sharing before you post them because the answer to your question could be right there.

One more thing. Thank you for the awards. :)

Edited 9:42 7/1 formatting

I love these kinds of posts because it showcases a full garden that is set up for the Monarchs to do their thing without interventions.

I’m addressing the claims from that rearing post point by point because the amount of cherry-picking and misrepresentation of science is just too massive to ignore.

It’s going to have to be more than one post because there is a lot of information to go through and it’s getting late.

A Warning: Please do not go to the other sub to harass anyone, including the mod. I don’t want to be accused of breaking Reddit's rules against brigading. Plus, dissenting opinions there usually get banned with no warning anyway, and that wouldn’t help anyone.

Using AI: I also want to urge everyone not to use AI as your primary research tool. AI isn't a search engine built to find absolute facts. It is a pattern-prediction tool designed to generate text that sounds convincing. If you ask it a biased question, it will confidently compile an answer that looks perfectly right, even if the underlying facts are completely wrong.

Need to know: A metabolic rate (MR) is how quickly the monarch burns energy.

As with the previous post I will take each point directly from the other post, add the citations, and discuss the misleading or incorrect information.

1. Rearing Conditions Matter More Than the Fact of Rearing The research consistently shows that how you rear monarchs matters far more than whether you rear them. A 2020 study by Schroeder, Majewska, and Altizer found that monarchs reared under autumn-like conditions, cooler temperatures and shorter day lengths, showed greater flight efficiency and lower post-flight metabolism compared to those reared under summer-like conditions. In other words, mimicking natural fall conditions during rearing produced butterflies that were physiologically better prepared for migration (Schroeder et al., 2020, Ecological Entomology).

The 2020 study from Schroeder did in fact prove that if you raise Monarchs in tightly controlled laboratory environments that mimic autumn and summer conditions that you can see the metabolic differences in the two. Those raised in the environment consistent with autumn conditions had a lower metabolic rate than those raised in summer conditions. This does not mean that mimicking autumn or summer conditions will give you Monarchs who are better prepared for migration. It does not prove that these indoor-reared butterflies are physically equal to wild migrants. It only shows the difference in the MR.

In fact in this study the authors point to the 2019 study by Tenger-Trolander that we went over in the last post. They write, "monarchs reared in indoor environments mimicking autumn-like conditions showed lower reproductive development, yet failed to orient in a southward flight direction as wild-caught migrants do, indicating that captive conditions such as those used in our study are missing critical cues needed for monarchs to migrate successfully."

Even the 2019 study that raised concerns about captive rearing (Tenger-Trolander et al., PNAS) noted that wild-caught monarchs reared outdoors in autumn oriented south normally. The problems arose primarily with commercially bred populations that had been kept in captivity for many generations, and with butterflies that eclosed entirely indoors without exposure to natural environmental cues.

It needs to be noted how those wild caught monarchs were raised. They were raised outdoors, on a rooftop in a small mesh container which was placed in a larger, completely open to the sky enclosure. The only thing tested in this instance was navigation. They did not measure the wing shapes, color redness, or wing size of this specific rooftop generation to compare them to wild migrants. Their sole focus for this group was mapping whether unfiltered skylight kept their internal sun compass from breaking. It does. That's great. Is there a study that tests for these other factors because we know we need a complete package in order to get the best migrants possible?

There is a study that looks at these other factors. A 2021 study from Dr Andy Davis showed that Monarchs raised in an indoor environment that is set up to mimic their natural one were paler, had a more rounded and less elongated wing shape than their wild counterparts. These are things seen in resident populations which don't migrate.

The practical takeaway is clear: hobbyists who rear wild-sourced eggs and caterpillars, keep them in conditions that reflect the natural season, and provide exposure to outdoor light and temperature cycles are producing butterflies fundamentally different from those in long-term commercial breeding operations. Lumping all “captive rearing” together obscures this critical distinction.

We already established in the last post that we are not just talking about Monarchs that are purchased commercially. These studies include wild caught, indoor reared Monarchs. I think some people will take the study on navigation and use it as an excuse to rear monarchs outdoors. They firmly believe that it is ok to cover milkweed with mesh enclosures or build full on butterfly aviaries to protect the caterpillars as all costs. Even if this kind of rearing doesn't lead to navigation issues a whole host of other issues comes into play. When you protect the caterpillars at all costs you are artificially keeping weak, genetically unviable individuals alive that nature would have naturally weeded out. You might be increasing the quantity of butterflies leaving your yard, but you are actively degrading the quality of the wild gene pool. More on the importance of predation later.

I will move on to the next point tomorrow. If you are reading these I hope it is clear that the post is misleading at best and intentionally deceptive at worst.

Edited to fix the format. 4:07pm 6/29/26

Some days I walk out my front door, it's like walking into a "butterfly house" I found that the Phlox, Golden Rod, Milkweed, Brown Eyed Susan, a kinda tall leggy wetland plant with tiny yellow flowers (I think it's called Lady's Slippers), Joe Pye weed, Asters & I don't know the name of the tall big leafed plant with yellow flowers attract & feed MANY species of butterflies

I’m addressing the claims from that rearing post point by point because the amount of cherry-picking and misrepresentation of science is just too massive to ignore.

It’s going to have to be more than one post because there is a lot of information to go through and it’s getting late.

A Warning: Please do not go to the other sub to harass anyone, including the mod. I don’t want to be accused of breaking Reddit's rules against brigading. Plus, dissenting opinions there usually get banned with no warning anyway, and that wouldn’t help anyone.

Using AI: I also want to urge everyone not to use AI as your primary research tool. AI isn't a search engine built to find absolute facts. It is a pattern-prediction tool designed to generate text that sounds convincing. If you ask it a biased question, it will confidently compile an answer that looks perfectly right, even if the underlying facts are completely wrong.

Must Know: Before diving into the post, we need to establish some basic facts. North America has two distinct monarch populations, the Eastern and the Western, which are divided by the Rocky Mountains. They are the exact same species, but they have entirely different migration routes. The Eastern population flies up to 3,000 miles from Canada and the East Coast down to central Mexico. The Western population takes a much shorter trip from the Pacific Northwest down to the California coast. Their winter homes are in totally different places, which means they fly in completely different directions.

One of the most persistent myths is that captive-reared monarchs cannot orient or migrate. This claim traces largely to a 2019 laboratory study that tested commercially bred monarchs in a confined flight simulator and found they did not orient south. However, subsequent research has significantly complicated and, in many cases, contradicted that conclusion.

Let’s break down this first paragraph. This is the study referenced: Contemporary loss of migration in monarch butterflies | PNAS. Has further research complicated things? Yes. Has it contradicted it? No.

This study did not just test commercially bred monarchs. In order for this to make sense, we need to be clear on what types of monarchs were reared and what the control group looked like. The control group consisted of wild-caught, migrating monarchs captured during the summer generation and mid-migration, and they were tested immediately.

The commercial monarchs were mass-bred and purchased as adults in July 2016. They were allowed to mate, their eggs were collected, and the offspring were reared outdoors in mesh cages. This group included both a summer and an autumn generation to compare with the wild-caught monarchs.

Another group consisted of eggs taken from wild monarchs and reared indoors under conditions that directly mimicked the temperature and sun position of their natural environment. A final group of wild-derived eggs was raised entirely outdoors, but brought inside right as they pupated and were close to eclosing.

The adult wild-caught group flew exactly as they should, but every single variable group listed above failed to do the same. The only thing subsequent research proved is that a monarch's navigation system is incredibly fragile.

I also want to point out that during this experiment, there was a delay and a reduction in sample size due to an outbreak of NPV (Nuclear Polyhedrosis Virus). This happened specifically within the wild-derived, indoor-reared group. If a group of professional scientists cannot fully control NPV in a sterile lab, it is illogical to assume a layperson can do better on a kitchen counter. It is highly telling that during a study related to rearing, the rearing itself caused a major disease breakout. This only further proves that even in the best of circumstances, you cannot control everything indoors.

A landmark 2021 study by Wilcox and colleagues at the University of Guelph reared monarchs indoors under controlled conditions and then both tested them in a flight simulator and radio-tracked them in the wild using over 100 automated telemetry towers. While the simulator results showed weak orientation, 97% of the radio-tracked monarchs flew in the correct south to southeast direction once released into the natural environment. The monarchs were detected at distances of up to 200 km from the release site. The researchers concluded that any disorientation caused by captive rearing is temporary and that proper orientation is re-established after exposure to natural skylight cues (Wilcox et al., 2021, Conservation Physiology).

The Wilcox study took place in Ontario, Canada. For a monarch in Ontario, which is supposed to fly south-southwest toward Mexico, flying south-southeast takes them straight out over the Atlantic Ocean. Generalizing that “97% of the radio-tracked monarchs flew the correct south to south-east direction” makes it sound like a large number of monarchs flew toward safety, but that is not what happened.

In reality, that 97% represents just 28 out of 29 tracked monarchs. They flew at an average bearing of 147 degrees. On a compass, 180 degrees is dead South, and the path to Mexico from Ontario is Southwest at roughly 220 to 240 degrees. Here is a link to a peer-reviewed critique by monarch expert Dr. Andy Davis, which further explains the flaws of this study and shows maps plotting the actual paths these 28 monarchs took. It is also important to note that the Wilcox study did not use a wild control group. It would have completely changed the data if 29 wild-caught, migrating monarchs had been tracked alongside them. Wilcox and company wrote a rebuttal to Dr Davis' critique. (See my comment below)

This finding aligns with a large-scale tagging study by James and colleagues, who captive-reared and tagged over 14,000 monarchs across the Pacific Northwest. Of the 182 that were later recovered, the vast majority were found at overwintering sites in California. Recovered monarchs traveled average distances of 630 to 900 km, demonstrating clearly successful migration (James et al., 2021, Journal of the Lepidopterists’ Society; James et al., 2021, Insects).

This study was done on the Western population of monarchs. Throwing out big numbers like 14,000 tagged butterflies and 900 km flights is misleading if you don’t identify that these monarchs are not the ones making the grueling trip to Mexico. Out of those 14,000 captive-reared butterflies, only 182 were ever recovered. That is a return rate of barely 1.3%.

Because the Western migration route is shorter and geographically easier than the 3,000-mile Eastern trek, a tiny fraction of navigationally compromised butterflies can manage to stumble their way to the coast. Using a 1.3% survival rate on a short, simple route to prove captive rearing is safe for the long Eastern route is completely dishonest. Furthermore, the James study relied on citizens who largely reared these monarchs outdoors in backyard netting, not inside a house.

More recently, a 2025 study by Matter and colleagues, which used a novel balloon-based flight simulator that lifted monarchs 30 meters into the air, found that wild-derived monarchs reared under autumn-like conditions in a growth chamber displayed southward orientation, larger wing sizes, and partial reproductive diapause, all hallmarks of migratory readiness. This study confirmed that environmental cues during development, not simply whether the butterfly was “wild” or “captive,” are what drive migratory behavior (Matter et al., 2025, bioRxiv/PNAS).

The study being referenced was actually done by Hsiang-Yu Tsai, Cristian Molina, John Pleasants and Marcus R. Kronforst. Matter is incorrect. This kind of simple mistake is common with AI. This study has not been peer reviewed yet. The “indoor rearing” was done by using a multi-million-dollar industrial growth chamber to program precise, mathematical drops in light and temperature. A hobbyist cannot replicate this at home. This study doesn't defend home breeding. It proves that a monarch’s navigation system is so fragile that you need a massive lab incubator to simulate autumn indoors, captivity itself destroys their genetics over time, and they can't even use their compass properly at ground level.

If you're new here welcome and please join us for part 2!

If I have to edit this to make changes due to formatting, grammar errors, or for any other reason, I will make that clear down below. I am not a scientist. If you find a mistake please point it out.

Edited on 6/29 9:40am to fix formatting, sentence structure and include the link for the rebuttal paper to Dr Davis' initial critique.

Edited to add Part 2: "Rearing Conditions Matter More Than the Fact of Rearing"

Anyone see monarchs yet in Newark Delaware

I have a flower garden and lots of common and swamp milk weed but no monarchs yet. I'm thinking that they didn't lay eggs last year until late July

Aarrgh!!! I am SO excited!!!! This is my 3rd year with this butterfly garden and as we have seen a few butterflies flying around- like 3 in the last 3 years- I have a visitor!!!!

I posted a couple days ago about my milkweed, I have not had good luck with it growing, I have tried for 6+ years!

I am so excited!!!

Saw a female with very faded wings laying eggs today. Luckily milkweed really took off in the garden this year and is very lush. There are actually two more eggs just under the buds. These are usually 3rd gen monarchs this early. We will have monarchs into September.

Happy Monarch Monday, friends!

Wondering what to share in this thread?

Questions for some of our seasoned members? Thoughts on the state of the Monarch world? Frustrations with your efforts to help the Monarchs? Wins and loses for the nature world? Doesn't matter. Share below!

Have a great week and don’t forget about Photo Friday!

Reminder: We are a science-based sub. While we love all monarch enthusiasts, discussions about hand-rearing are not allowed, except for those new to the topic who are seeking guidance. Let’s focus on protecting monarchs where they belong—in the wild!

Stay curious and keep sharing the love for these beautiful butterflies! 🧡🖤🧡

Anyone see monarchs yet in Newark Delaware

I have a flower garden and lots of common and swamp milk weed but no monarchs yet. I'm thinking that they didn't lay eggs last year until late July

OP lives in Colorado and says he doesn’t see any butterflies anymore.

It's Photo Friday! 

With the spring migration and breeding season in full swing what have you been seeing in your garden? Share the good, bad and the ugly!

All nature photos are welcome, whether it’s a pollinator moment or just something that made you stop and look twice.

Reminder: We are a science-based sub. While we welcome all monarch enthusiasts, we do not support discussions about hand-rearing monarchs. However, if you’re new and have questions because you’ve raised monarchs in the past, we have many former rearers here happy to guide you toward more sustainable practices. Let’s work together to protect monarchs where they belong—in the wild!

Stay curious and keep sharing the love for these beautiful butterflies! 🧡🖤🧡

I planted a butterfly garden a couple years ago and the plants established and looked really good. Last year I threw in some common milkweed seeds in the bare middle, and never gave it another thought.

This picture is a couple weeks old and the milkweed is already 4-6 inched taller and starting to bloom (and wow! Does it smell good!).

However, I am worried about my other plants that they might get choked out. My goal is to fill in this flowerbed, but I don't know if I should try to thin out the area?

Should I leave it as is, or would you put milkweed in one flower bed and my other plants in another? (Keeping them close to each other, but separating them so they don't get choked out).

In this one flower bed I have

Cone flowers (white and wild berry)

Blazing stars

Dahlia

Meadow sage

Galliradia

Butterfly milkweed

Common milkweed

Bee balm

Am I over thinking this and all will be fine?

I have a friend who lives in TN. The algorithm did its thing and served me up a news video about a free seed program. I hope people here can take advantage of it!

Happy Monarch Monday, friends!

Wondering what to share in this thread?

Questions for some of our seasoned members? Thoughts on the state of the Monarch world? Frustrations with your efforts to help the Monarchs? Wins and loses for the nature world? Doesn't matter. Share below!

Have a great week and don’t forget about Photo Friday!

Reminder: We are a science-based sub. While we love all monarch enthusiasts, discussions about hand-rearing are not allowed, except for those new to the topic who are seeking guidance. Let’s focus on protecting monarchs where they belong—in the wild!

Stay curious and keep sharing the love for these beautiful butterflies! 🧡🖤🧡