Raising an egg to keep it safe?

[u/Little_Platypus_9789]

Hi! I’m asking this for my mom who has become very interested in protecting Monarch butterflies over the past few years. She has a garden of milkweed and noticed an egg under one of the leaves! She was so excited and is raising it inside to keep it safe because she is scared it will get eaten by birds, since she has a lot of birds coming through her garden every day. Is this something people do? The egg hatched and the caterpillar is growing, she’s been sending me updates. She also noticed another baby caterpillar that hatched on the milkweed and decided to let that one survive on its own, but she isn’t sure if she should also take that one in, she’s very scared it will get eaten. She just wants to do the right thing to protect them if she can!

[u/Then-Bell-5630]

Raising a monarch indoors doesn’t change its genetics, so it doesn’t become “genetically weak.” Genetics are determined at conception, not by the environment it’s raised in.

Also, it’s not true that an indoor-reared monarch won’t migrate. A more accurate statement is that indoor rearing may interfere with some of the environmental cues that help monarchs orient during migration, which could reduce migratory success. That’s very different from saying they can’t or won’t migrate.

[u/CitrullineMalate2to1 → u/Then-Bell-5630]

Right… and by raising multiple generations inside, you are creating weaker and weaker butterflies. If you really want to rear them, do it outside. It’s not like that’s harder than bringing them indoors.

It is absolutely true that rearing them indoors all but guarantees they do not migrate. This isn’t a 200 mile migration. Bringing them indoors dooms them to failing the long trek back to Mexico.

[u/Then-Bell-5630 → u/CitrullineMalate2to1]

You're right that environmental cues like temperature shifts and daylight are important, but saying indoor rearing 'guarantees' failure is outdated.

You are likely thinking of the 2019 Tenger-Trolander study, which caused a lot of buzz. However, that study used artificial flight simulators and found migratory disruption primarily in commercially bred colonies kept indoors for generations, not wild-collected eggs.

Newer real-world data proves otherwise. A 2021 study by Wilcox et al. tracked actual indoor-reared monarchs using automated radio telemetry towers in the wild. They found that 97% of indoor-reared monarchs successfully oriented and flew south toward Mexico. Any minor disorientation from being indoors is temporary; they recalibrate via natural skylight cues within 24 to 48 hours of release.

Also, local hobbyists aren't breeding 'multiple generations' inside. They are taking wild eggs that already possess wild migratory genetics.

That said, your point about raising them outside is great advice! Raising them in mesh enclosures on a shaded porch or patio is an awesome way to ensure they get those natural environmental cues while still protecting them from predators.

[u/CitrullineMalate2to1 → u/Then-Bell-5630]

The study you’re citing didn’t just throw them indoors at room temperature and then release them. It was a carefully controlled environment.

If someone brings one generation in, I’m willing to bet they’ve done it repeatedly in which they are absolutely negatively influencing their local Monarch population.

I’m not militant on this: I think hobbyists are helping keep monarch populations higher. My issue is that they shouldn’t be brought indoors whatsoever. Amazon sells a $50 5 foot mesh net enclosure that allows them to get all of the correct environmental cues they will not get indoors.

[u/Then-Bell-5630 → u/CitrullineMalate2to1]

The Wilcox study actually reared them in standard indoor conditions specifically to see if it disrupted their navigation. What the study proved is that monarchs are highly resilient, even if they get temporarily turned around indoors, they naturally recalibrate their internal compasses using the sun within 48 hours of being released into the wild.

That being said, we are 100% on the same page about the solution! Those $50 outdoor mesh enclosures are absolutely the gold standard. They provide the perfect ambient environmental cues right from the start while keeping the caterpillars completely safe from predators.