Look who's here................
Just when I thought it was time to take a step back from Monarchs for a few months, as our weather becomes colder and colder, it seems they have other ideas.
Look who's here................
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We have a man down. Largest caterpillar hasn't made it.
It was growing so well but during last weekend we noticed it seemed like it was shrinking.
As the days went by it did shrink in size and I noticed it had a little red 'pooh-like' button at the end of its body which didn't drop off. Monarch caterpillar pooh is usually quite green and is called frass, by the way.
Last night largest caterpillar was writhing on the plant and this morning it was curled up and 'kind of' still attached to the plant by an end foot.
Clearly it wasn't going to make it, so I did the kind thing and euthanised it by wrapping it in a paper towel and placing it in the freezer.
Monarch Caterpillars and Butterflies need warmth to survive.
By wrapping them in a paper towel (gently but firmly) and placing it in the freezer, they can't move around and the cold sends them quickly to sleep before they freeze.
It's unfortunate to have to do it, but preferable to allowing a lovely creature to suffer.
On a positive note, middle caterpillar is now huge and very close to forming its chrysalis.
Smallest caterpillar is a good middle-size and eating well.
Our weather has become really cold now. Where we live in New Zealand is referred to as 'the Winterless North', however today the morning temperature was 7 C (45 F), so no wonder our caterpillars are enjoying being inside our house where it's a bit warmer than that.
When the sun comes up each day, I place their plant into the sunny part of the window so they can soak up the warmth.
My final 3 Monarch caterpillars for the season, here in New Zealand, are still doing well.
I have them in our lounge with a heater in the room, set to turn on early in the morning to take the chill out of the air. Our temperatures are so very cold at the moment with snow in southern parts of the country. We live in the far north of New Zealand where there is no snow, however our morning temperatures are coming in at a very cold 6 degrees Celcius (42.8 Fahrenheit) in the morning.
Just look at big caterpillar in the picture above. At one stage I wondered if it would even survive, because it was quite sluggish when I found it on a swan plant outside in the cold, several weeks ago. Now it's growth unlimited as it steams towards being large enough to form its chrysalis quite soon.
........and, the other two caterpillars are doing just as well.
Small caterpillar is rapidly heading towards being a large caterpillar. Tiny caterpillar is now medium in size. I place their plant in the sun coming through the window, during the day, and the heater warms them the rest of the time.
Quick progress update.
Biggest caterpillar is 15 mm long.
Middle caterpillar has had another shedding of skin and is 7 mm long.
Smallest caterpillar is 4 mm long.
They're not walking around the plant as much as they might if it were Summer with lovely warm weather to keep them active, however they're eating lots and seem perfectly happy.
It's very cold here now, just as we expect June to be in New Zealand - even up here in the so-called Winterless North and cold temperatures slow caterpillars down a lot.
So far, so good, however.
Tiny caterpillar has been busy. It has shed its skin for the first time and will do this 5 times before forming it's chrysalis.
Tiny caterpillar is now about 3mm long. It's an active caterpillar and moves well, around the leaves, and I often have to search to see where it has got to. As you can see, it has eaten a lot of the leaf that its on. I'm fascinated because, even if it goes off this leaf, it later goes back to it and carries on eating where it left off.
In the picture below, look above the caterpillar and you will see a hole it ate when it was really tiny. Notice how the eaten section hasn't gone right through the depth of the leaf, but rather it has just eaten around the veins.
I'm guessing that its tiny, immature, mouth can't yet cope with nipping the back of the leaf vein to drain out the toxins in the white 'milk', so it has eaten around the veins to avoid the toxins that way.
Caterpillar One has shed its skin again. What a star !!!
I've now decided to refer to the caterpillars by numbers because the one I was calling small caterpillar, to start with, is now medium sized. It will now be referred to as Caterpillar One.
Yesterday, Caterpillar One shed its skin again. My photo (above) was taken just after the event. Notice how its face and feet are still fairly clear in colour.
In particular, notice the face plate that fell off after the skin molt process. The face plate is the little black dot you can see below the caterpillar - its lodged in the joint of the lower leaf.
When a Monarch Caterpillar sheds its skin, it eases the unwanted skin downwards from the back of the head. As the skin comes to each set of feet it pulls them through, two by two, and carries on until the skin has been literally 'walked out of'. Sometimes they stay on the plant to accomplish this process. At other times they wander off the plant to find a rough surface that will catch on the skin and help draw it down, as they slide themselves out of it.
The process is called Ecdysone, being the molting hormone of insects.
All insects can only grow by periodically shedding their exoskeleton until the adult (in this case, the butterfly) emerges after the final molt. This is why Monarchs must shed their skin in order to grow bigger.
After each molt, and while the new skin is soft, the caterpillar swallows air to expand its body. Then, when the new skin firms, they let the air out and this provides them with room to grow within the new skin.
During this process of the old skin being 'stepped out of', the old face plate falls off.
I have watched this happen, with fascination. Yes, it's the complete black shiny face plate that drops off to reveal a clear version of the same, underneath. Within a day the new face colours up to black again and the caterpillar gets back to its eating.
Today Caterpillar One is looking magnificent and, this morning, has already an entire leaf.
Small caterpillar is into it's 3rd instar. It is now a lot more lively and almost 20mm long.
My photo shows it finishing off a leaf that it began eating last night.
Instars are the different stages Monarch caterpillars pass through, shedding their skin between each stage, until they reach a maturity that allows them to form their chrysalis.
Monarch caterpillars eat only milkweed leaves. The leaves contain a white sticky sap that is a mild poison. Its bitter taste warns away many animals and insects that try to eat the plant. Certain insects however, including monarch butterfly larvae, are reasonably immune to the toxin. The clever caterpillar nips the main vein of a leaf, at the point where the leaf attaches to the stem of the plant. This drains away the majority of the toxic sap before the caterpillar feeds. As the caterpillar grows, its body accumulates the glycosides, making it unpalatable to predators. The yellow-black caterpillar colouring gives a warning to predators that the caterpillar is toxic.
Unfortunately this doesn't deter the Asian paper wasp from successfully preying on the caterpillars in New Zealand and almost wiping out many Monarch caterpillar groups.
Tiny caterpillar is also doing well and now at 2nd instar stage.
It's about 10mm long now and, as you can see, its Monarch caterpillar colouring is becoming more prominent.
To me it looks as if all tiny caterpillar does is sit all day. Upon checking this, I found it to be correct because apparently 2nd instar caterpillars don't actually eat a lot - perhaps a leaf or two a day.
Very tiny caterpillar is growing well, too, and I'll show it to you in another post. Right now it's still so tiny that I have trouble finding it on the leaves - but it is there.
As for the two eggs?
Well they are both now quite dark, so it's anyone's guess if they'll hatch or not. I'm hoping.
Opua, New Zealand.
Keen butterfly photographer and raises Monarch Butterflies for release.
" I'm crazy about butterflies and enjoy sharing the beauty and wonder of their transformations."
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