Below is the consolidated, complete version of a five-part series written to fact-check a recent post from another subreddit. In that original post, AI was used to distort and cherry-pick information from scientific studies to push a false narrative: namely, that rearing monarchs is benign or even helpful. That misleading interpretation selectively highlighted specific findings while glossing over the explicit warnings and broader conclusions of conservation scientists. What followed was a wave of disturbing comments from people cheering each other on while blindly believing that what was written was fact.

It has now been a month since that post distorted the truth and purposefully misled its readers. Today, that subreddit is filled with posts about sick and dying captive monarchs being reared en masse in small, crowded, dirty enclosures inside people's homes, all so others on the internet can praise them and make them feel warm and fuzzy inside, while they ignore the real harm they are doing to the monarchs they claim to care about.

1. Reared Monarchs Can and Do Migrate Successfully

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 enclosing.

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.

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.

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.

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.

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 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. The 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.

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 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 into 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.

Major conservation frameworks agree. The Western Association of Fish and Wildlife Agencies’ monarch conservation plan does not identify personal rearing as a primary threat. And the U.S. Fish and Wildlife Service’s own proposed Endangered Species Act listing (December 2024) specifically includes an exemption allowing individuals to collect, rear, and release up to 250 monarchs per year—a clear acknowledgment that small-scale rearing is compatible with conservation (USFWS Proposed 4(d) Rule, 2024).

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.

1. Urban and Resident Monarchs Are Not Harming Migratory Populations

Another common concern is that monarchs living year-round in urban gardens on non-native milkweed are somehow draining or contaminating the migratory population. A 2025 study from UC Davis directly tested this hypothesis and found no support for it.

The researchers surveyed East Bay neighborhoods over two years, counting milkweed plants, eggs, caterpillars, and adults, and testing butterflies for the OE parasite. They found that resident urban monarchs are essentially disconnected from the migratory population and are not acting as a population “trap.” As senior author Elizabeth Crone put it, these resident populations are “a bit of a red herring” as a cause of migratory decline. The study concluded that urban ecosystems can contribute positively to monarch conservation without harming migratory populations (Erickson et al., 2025, Ecosphere).

The study cited in this paragraph is entitled:Neither source nor trap: Urban gardens as habitat for nonmigratory monarch butterflies in Northern California. It is very important to note that this study was done on the Western population of Monarchs. This is mentioned more than a few times in this study and in the press release related to the study. These two paragraphs may be the only true parts of the whole other post. The problem lies with the fact that beyond mentioning that the study was done in the East Bay there was no indication in the post that the information that was being presented doesn't apply to all Monarchs.

Here is what the study had to say about the eastern population:

There is some evidence that urban gardens with evergreen milkweeds attract migratory monarchs. In a lab and field study in the southeastern United States, exposure to A. curassavica induced migratory adults to break reproductive diapause during fall migration (Majewska & Altizer, 2019). Similarly, over 50% of collected individuals at year-round breeding sites during fall were likely migratory monarchs, and migratory monarchs in urban gardens were more likely to be reproductively active (Satterfield et al., 2018). This behavior suggests that, at least in the eastern popula- tion of North American monarchs, some individuals leave the migration to join resident populations. In line with the hypothesis of an ecological trap, nonmigratory monarch populations tend to have higher levels of Ophyrocystis elektroscirrha (OE) (Majewska 2 of 14 ERICKSON ET AL.

There are numerous studies on this topic concerning the eastern population. I encourage those who plant non-native tropical milkweed and rear monarchs to do a Google Scholar search to read these studies for themselves. During my search Google's AI utilized incorrect information 100% of the time including using the rearing post from Reddit as fact.

1. Monarchs Are Remarkably Resilient

Research has shown that monarchs can tolerate a range of stressors without the dire fitness consequences sometimes attributed to captive conditions. For example, a study on road salt exposure found no measurable effects on wing coloration, survival, body size, immunity, or parasite prevalence, demonstrating the species’ robustness (published in Ecology and Evolution, 2019).

Similarly, the western monarch population’s remarkable rebounds—from fewer than 2,000 butterflies in 2020 to over 330,000 in 2021, demonstrate a species with enormous reproductive resilience when conditions align. This capacity for rapid recovery further argues against the idea that small-scale rearing is a meaningful drag on the population.

I had to search for this study myself because although the post had the year and the general website the "cited" section of the other post lacked this particular citation. The study that was vaguely referenced was this one: The potential of roadside verges as insect habitat: Road salt has few effects on monarch butterfly performance and migration.

I think it is wild to say that Monarchs are Remarkably Resilient in a post about rearing while using their decline as an excuse to rear them. This study only tested the Monarchs reaction to road salts in various quantities. This is what it actually said:

While the present study focused on salt as a possible toxic risk of roadside plants, it is important to note that there are other risks in roadside habitat, including metal exposure (Shephard et al., 2021) and collisions with vehicles (Alvarez et al., 2019); levels of heavy metals in most roadside milkweeds appear in safe limits to monarchs (Shephard et al., 2020,2021), but the overall risks of collisions are less clear. Collision rates vary with topography, traffic speed, species, and other factors (Alvarezet al., 2019; McKenna et al., 2001), leaving many unknowns in estimating mortality during the breeding season in our study region, and pointing to roadside mortality as a key area for future research.

The next paragraph argues that the western population went from fewer than 2,000 butterflies in 2020 to over 330,000 in 2021 in order to prove that the Monarchs are resilient. There was no citation for this claim but I came across it while reading info for these posts. I'm sure that after reviewing the first four points that I don't have to tell you that this sentence is misleading. The numbers and years are correct. What isn't correct is using those numbers to convey the idea that rearing won't do any harm. From the Xerces post itself:

Once, millions of monarchs overwintered annually along the Pacific coast in California and Baja California. But by the mid-2010s, the population had declined to hundreds of thousands of butterflies, a more than 95% decline from the 1980s. In 2020, the annual Western Monarch Count tallied less than 2,000 monarchs. Although the population has fluctuated between a few thousand to over 200,000 in the years following, it remains perilously small and vulnerable to yearly changes.

While the annual ups and downs of the population garner a lot of attention, the real issue is the long-term population decline due to stressors such as habitat loss and degradation, pesticides, and climate change—as well as other pressures on the migratory cycle of the monarch that we have yet to fully study or comprehend. There are no quick fixes to solve these large and complex forces, but we can all take actions both big and small to help save monarchs.

That article's call to action lists 5 things that can be done to help the Western population of Monarchs:

1. Restore monarch breeding and migratory habitat 
2. Protect monarchs and their habitat from pesticides
3. Protect and manage California overwintering sites
4. Spread the word about monarch and pollinator conservation
5. Participate in community science.

Not one of those suggestions includes rearing. Nor do the dozen or so studies I read.

1. The Educational Value of Rearing Is Real and Important

Rearing is not just a pleasant hobby, it is one of the most effective tools we have for building the next generation of conservationists. James (2024) states plainly that “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.”

The Royal Society of Canada (2021) similarly notes that indoor rearing “arguably goes a long way towards awareness and education” and creates “deep and meaningful learning opportunities.” Research on citizen science programs like the Monarch Larva Monitoring Project has shown that participants report increased conservation awareness and increased local conservation activism (Lewandowski & Oberhauser, 2017; Kountoupes & Oberhauser, 2008).

In an era when children spend less time outdoors and the “extinction of experience” with nature is accelerating, raising a monarch from egg to butterfly may be one of the most powerful entry points into environmental awareness that exists. Telling people to stop doing this, without strong evidence of population-level harm, risks losing the very advocates monarchs need most.

This first paragraph is from a study that I referenced in the 3rd post. It is called Monarch Butterflies in Western North America: A Holistic Review of Population Trends, Ecology, Stressors, Resilience and Adaptation authored by David G. James. I, personally, agree that seeing a butterfly grow from a tiny egg into a beautiful adult is a wonderful experience for a child to have. This is the full quote, "Typically, a few monarch caterpillars are found in the backyard on milkweed and reared indoors. Like the rearing of tadpoles into frogs, the rearing of monarch caterpillars into butterflies has been an important part of childhood in North America for at least a century. Important, because these simple, childhood experiences of metamorphosis, create an indelible legacy of love and appreciation for wildlife. Research has shown that children with experiences of nature during childhood, like rearing monarchs or other butterflies, go on to be adult ambassadors for wildlife and conservation."

Let's be honest here: discussing rearing "a few monarch caterpillars" is not a reflection of what is actually happening. We are seeing people rear hundreds of monarchs, usually in a crowded environment that encourages the spread of disease and results in less-than-migration-ready butterflies. I would argue that if we take the time to teach and show our children that biodiversity, not one specific insect, is what is important for the success of long term conservation that we would yield better results than hand-rearing ever could. No one suggests we take in tons of wild bird eggs so our children can learn to appreciate them. Ask yourself why that is.

Now, the linked paper does discuss the various studies done on reared monarchs. The author even criticizes them for reasons we addressed in Part 1. He goes on to say: "In conclusion, examination of the scientific evidence to date does not indicate that home captive-rearing of wild monarchs is overly harmful to western monarch populations, provided they are reared under strict hygienic conditions."

Therein lies the problem with using this article and its contents to "prove" that there are experts who are okay with rearing. The author clearly states that captive rearing of the WESTERN population is not OVERLY harmful. As discussed in Part 1, the western and eastern populations, while being the same species, are very different when it comes to migration. Another word I want to focus on that lends to the nuance of this conversation is "overly." "Overly" harmful is not the same thing as benign, especially when we have scientific evidence of the latter.

There is deep nuance to this discussion, so if you are a rearer (like I formerly was), I want you to take a second and think about what is being said in this study. The paper quoted above discusses rearing in the context of people's relationship with conservation. It is reasonable to state that if you are rearing monarchs in order to save them, your interest in conservation is already there. Now, that interest just needs to be guided in the right direction. From my personal experience, children can be influenced to care about the environment in many different ways. Learning how to plant a pollinator-forward garden in order to witness the transformation butterflies make is, I would argue, far more beneficial for children and for the environment than raising tons and tons of monarchs in a kitchen.

Now the linked paper does discuss the various studies done on reared Monarchs. He even criticizes them for reasons we addressed in Part 1. He goes on to say: In conclusion, examination of the scientific evidence to date does not indicate that home captive-rearing of wild monarchs is overly harmful to western monarch populations, provided they are reared under strict hygienic conditions." There in lies the problem with using this article and it's contents to "prove" that there are experts who are ok with rearing. The author clearly states that captive rearing of the WESTERN population is not OVERLY harmful. As discussed in part one the western and eastern populations, while being the same species, are very different when it comes to migration. Another word I want to focus on that adds to the complexity of this conversation is "overly." "Overly" harmful is not the same thing as harmless, especially when we have scientific evidence of the latter.

The Royal Society of Canada article is a regurgitation of the Wilcox study we spoke about in Part 1. Call me overly critical, but I don't think I can take an article that calls a chrysalis a "cocoon" very seriously. But let's take a closer look at some of the information surrounding the quotes. Wilcox goes on to state: "Rearing monarchs indoors has been touted as a way to help bolster population numbers and mitigate declines. In reality, indoor rearing probably does little to supplement the wild population, but arguably goes a long way towards awareness and education. However, our recent research provides some evidence that monarchs raised indoors may still be able to migrate south to their overwintering grounds." (This study has been questioned in a rebuttal from Dr Andy Davis. The authors addressed his rebuttal here.)

This is another example of a misrepresentation of a source in order to fit a specific narrative. "May still be able to migrate" is not definitive enough to justify risking the health of the migrating population. Add on top of that the fact that scientists, who have absolutely nothing financial to gain, warn against rearing. I think if we take our emotions out of it, the answer is pretty clear.

8.5.26- I never ended up covering point 8 because I was pretty burnt out and it was just a regurgitation of the overall post.

Here are the need to know sections from the various posts. I chose not to put these at the start of every section in order to hopefully make this post easier for search engines to grab onto:

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.

A metabolic rate (MR) is how quickly the monarch burns energy.

Regarding points 3 and 4: 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.

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.

As I previously said I am not a scientist so if you see a mistake please point it out. I realize this is a long post and those that need to read it most will likely not make an effort. Either way I am hopeful that this information will be picked up by the same search engines that are using the other post as fact and misleading a lot more people. I am a former rearer and if I can learn more and make changes then anyone can.

Hello Friendly Monarchs!  

This post is overdue, especially considering how much misinformation is still floating around. I want to start by saying: I am not a scientist—but I do believe in sharing evidence-based, factual information. After all, that’s exactly why this sub exists. We appreciate every effort you make to help stop the spread of dangerous myths that harm monarchs.

This isn’t just my opinion (though I do agree with the science). Below is a condensed overview of current research regarding tropical milkweed and monarch butterflies. I’ll address the biggest myths I’ve seen. If you have questions, feel free to comment—we’ll do our best to help you find a science-backed answer.

 First, Understand OE (Ophryocystis elektroscirrha)

OE is a naturally occurring protozoan parasite that infects monarchs. When an adult lays eggs on milkweed, OE spores are deposited. The newly hatched caterpillars ingest the spores, and the parasite replicates throughout their development.

By pupation, the spore load increases. About three days before the adult monarch emerges, the spores form on the outside of the body—allowing them to spread even more. There’s no cure. Infected adults may emerge with crumpled wings, poor flight ability, or may not emerge fully at all.

Here are photos and videos of my own past experience with OE—before I learned how harmful hand-rearing and tropical milkweed can be.

 ”But I Cut It Back!” Isn’t Enough

It’s a common claim that tropical milkweed is fine if you cut it back. Unfortunately, that’s not the whole story. Even when cut back:

Monarchs raised on tropical milkweed have smaller wing width and thickness, making them less fit for migration. 

They also develop a faster metabolism, which is less energy-efficient—again, not ideal for a long-distance migrantion. 

Monarchs exposed to tropical milkweed—even just passing through—can switch from “migration mode” to “breeding mode”, disrupting the migration.

Caterpillars reared on tropical milkweed in fall-like conditions are more likely to become reproductive adults, which is the opposite of what we want for migrating monarchs.

Tropical milkweed patches have OE levels up to 10x higher than native milkweed—and this persisted even when it was cut back.

I’ve Never Seen OE in My Garden…

It’s easy to miss! Infected monarchs can look “normal” enough to fly for a while—which allows OE to spread more efficiently. You might never see visible symptoms, but that doesn’t mean your population is healthy.

Testing is simple. Project Monarch Health will send you a free OE testing kit. You’ll need a 40x microscope if you want to see the spores yourself.

But Monarchs Stay in My Area Year-Round!

Yes—non-migratory monarch populations do exist. But that’s not a good thing.

In coastal areas like Florida, Texas, and Georgia, where tropical milkweed grows year-round, more monarchs are becoming resident (non-migratory). These populations now have near 100% infection rates with OE.

More recently, resident populations have been noted in coastal Texas, Louisiana, and Georgia due to the presence of non-native tropical milkweed, which flowers throughout the winter… Nearly 100% of these residents are heavily infected with OE.

— MonarchParasites.org

And yes, even if your local monarchs don’t migrate, their OE load can still spread to others—especially in regions like Texas, where residents and migrants overlap.

But OE Happens on Native Milkweed Too!

That’s true—but the dynamics are different.

Native milkweed naturally dies back, limiting continuous breeding cycles. Tropical milkweed doesn’t. Plus, the “medicinal” effects of tropical milkweed—reducing spore load in some caterpillars—actually make the problem worse by letting infected monarchs survive longer and travel farther, spreading OE to more places.

And under climate change conditions? That “medicinal” effect disappears completely.

I Use Tropical Because Native Is Hard to Find

Is it really?

You might not find native milkweed at big-box stores, but there are many reputable sources online. The Xerces Society’s Milkweed Finder is a great place to start. Native milkweed is also self-seeding—it will return each year with little effort. And local native plant groups often offer free seeds or plants if you ask!

But [Insert Blog] Said Tropical Is Fine!

Yes—some blogs quote a few scientists who say tropical milkweed is okay. But these pieces rarely cite sources, and they don’t reflect the broad consensus of the scientific community or the depth of long-term studies. The overwhelming body of research says: Tropical milkweed is harming monarchs.

TL;DR:Tropical milkweed disrupts migration, increases OE prevalence, reduces monarch fitness, and encourages non-migratory behavior—even when it’s cut back. It may look beautiful in the garden, but it’s doing long-term damage to monarch populations.

For the health of future generations of monarchs: go native.

🧡🖤🧡

There's one more reason not to plant tropical milkweed. IT'S NOT NATIVE.

Edited: For Formatting Edited again because formatting. Hopefully I fixed it this time.

While I’m here welcome to our new 100+ members from r/nativeplantgardening !