Poll of the Day > Monarch rearing 2021

(+) Yeah! (+)

itt I will chronicle this year's batch of monarchs I'm rearing. Since middle school, I've done this from year to year to help give a few animals their best shot at surviving to adulthood.

Some pics from last year:


A few fresh chrysalis and some preparing to pupate


One of the adults from last year's batch (plus another in the background)

Day 1 (AUGUST 16)
I've been checking local plants every day for the last few weeks, and just today I started to see eggs and young caterpillars. They were all found on common milkweed. I transferred 12 eggs and 2 larvae into enclosures after removing aphids and washing the leaves.

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Wow this is fascinating. I thought they could only do this in the wild I didnt know people could help

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Mead posted...

I thought they could only do this in the wild I didnt know people could help

It can easily go wrong, there are reported cases of the butterflies failing to migrate after being raised by a caretaker.

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KodyKeir posted...

It can easily go wrong, there are reported cases of the butterflies failing to migrate after being raised by a caretaker.

I've heard this with respect to monarchs that come from commercial stocks that are genetically isolated from wild individuals. They haven't migrated for many generations.

I find mine in the wild, rear them with natural light cycles and immediately release after eclosion.

Also, only the last generation of monarchs will migrate south each year. Mid August is on the cusp of the beginning of the super generation.

Taking about 4 weeks to become an adult, this batch could result in both non-migratory or migratory adults, but probably non-migratory this early in the year.

The non-migratory adults live only 2-6 weeks, meaning their offspring in mid-to-late October will be wild-born and highly likely to migrate due to shortening photoperiod and increased temperature variation.

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Day 2 (AUGUST 17)

Eggs still eggs. A few are in a separate dish. They typically take 4 days to hatch from when first laid on the underside of the milkweed leaf. On the day before a caterpillar emerges, you can see a dark spot forming at the top of the egg (which is the pigmented head of the developing caterpillar seen through the egg casing).


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(continued)

Two larvae, showing the difference between first and second instar. An instar is a stage separated by molting. Monarchs go through five instars (hatching as first instar, molting four times into another caterpillar stage) and then its fifth and final molting results in a chrysalis. The smaller one at the bottom left (first instar) has emerged from the egg, but hasn't molted yet. The larger one has molted once, and is second instar, where you can start seeing the classic yellow-black-white coloration.


Yes, the black specks are caterpillar (called frass)

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Neat

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Day 3 (AUGUST 18)

not much to update. Eggs still eggs. Two caterpillars just munching away.



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Bugs are so neat sometimes

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The Mighty Monarch!!

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This is neat. We did this in 5th grade science class and I really enjoyed it.

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CinderLock posted...

The Mighty Monarch!!

CinderLock posted...

MruHAHAHAHAHAHAHAHAHAHA!

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Day 4 (August 19)

One of the eggs hatched--the very top one in this picture. The little guy crawled to the underside of the leaf to chill out. You can see some of the others show the pigmented head of the caterpillar inside, kind of looking like a blackhead. The farthest left one is VERY close to hatching.



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(continued)

Both of the caterpillars molted within the last day. The little guy is now second instar, and the bigger guy is third instar. LOOK HOW PRETTY HE IS. From here they start eating and growing a TON.



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Dang they getting thicc


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Bad news. Was moving them to individual enclosures tonight and it looks like bigger guy already ate little guy.

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Oh yikes. I guess thats nature sometimes

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This is great - I love bug stuff

I'd do it too but my landlord said no

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Day 5 (August 20)

All the eggs are now hatched. Everyone gets their own private room for now. No more cannibalism!



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Day 9 (August 24)

I was away for the weekend and lazy yesterday.
The largest guy is now 4th instar. Next molt and he'll be a big ol fat caterpillar ready to perform a final molt into a pupa (chrysalis). See him next to little second ones.

https://i.imgur.com/il74hBu.jpg

Can you see all 8 caterpillars here?

https://i.imgur.com/Knoa98I.jpg

I add moisture to the dishes to keep the leaves from drying up. Unfortunately this also facilitates the growth of mold, meaning I need to clean them up from time to time. I transfer them to fresh clean plates with moist paper towel and clean fresh milkweed. The old plate contents (poop and old leaves) get put in my compost, then I clean them in a water plus diluted bleach, then let them air dry.

https://i.imgur.com/qrvU5vE.jpg

https://i.imgur.com/cBsZ9io.jpg


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