So far it’s looking like a great year for the Monarchs. We had a patchy start, losing many of the small caterpillars, we think to the Paper Wasps & other predators. In the last few weeks, most of the young ones have survived & we probably have over 100 large caterpillars on the verge of heading off to pupate. Not a day too soon either, as their food supply is running short. Luckily Mum has Swan Plants & Bloodflower plants(Asclepias) dotted throughout her garden, & we’ve been ferrying our hungry babies over to her patch.Interestingly the Bloodflower pods are proving to be great source of food for the larger caterpillars. They are just at the stage where they are wandering off to find somewhere to pupate, so they turn up in unusual places & far from their food source. Weeding has drawn to an abrupt halt until they all turn into butterflies!

The life cycle is both familiar & a source of wonder. The butterflies are so colourful & mobile, they check the place out seeking sources of nectar & of course some where to lay eggs. We haven’t witnessed the courtship stage of life yet, it sounds fairly complex, the aim of the male being to get the female onto a low , firm place, this is achieved either by direct action on the part of the male, or by the use of his ‘hair pencils’ I told you it was complicated! These are glands which are situated on the tip of the abdomen, & secrete irristible butterfly perfume ( pheremones) which attract the female. Once he has her in his clutches the business part of the procedure begins, & once the two are secured together, the male will fly off holding onto the female & find a cosy place for a park up, this can apparently last from 2-14 hours, phew.

Monarch Butterfly Danaus plexippus

Once the female is mated, she seeks out the right plants to lay her eggs on, using sight, smell, & confirming her decision by drumming on the leaf with her front feet, to receive chemical signals. The above picture shows a Monarch on a Bloodflower, but they don’t often lay eggs on these, preferring the Swan Plant. The picture below is of a Swan Plant & if you look carefully you can see a tiny egg on the left hand side, just above the stalk.


The eggs are the size of a pinhead, & ribbed for extra strength (sounds like an ad for something!) Over 3 or 4 days the egg changes colour from pale creamy white to grey, & amazingly inside the egg, the caterpillar develops by feeding on egg yolk, it had never occurred to me that there might be yolk inside such a tiny egg.

To hatch, the tiny caterpillar chews a hole in the top of it’s egg, & hauls itself out, often stopping for a light snack of eggshell before it moves off to forage. The caterpillars are very efficient eating machines, which only stop when their skins get too tight, then they stop work & moult, sloughing off the old skin, & getting the next size up. The stage between 2 moults is called an instar, & monarchs have 5 instars, the last just before pupation. The 2nd photo below, shows a caterpillar, ready to pupate, it’s hanging from a silk pad that it has woven. It stayed like this all of one day & night, & changed in the morning. This is how you often find them, attached to all sorts of things, & in all sorts of unlikely places. I took a photo of one, just changed with the old skin still stuck at the top, it was twisting about to release it, alas I took it at high pixcels & can’t figure out how to shrink it, so it’ll fit on here. What a pain! The 3rd pic is of a freshly turned chrysalis, they are exquisite things with the gold filigree decorations. With luck I’ll manage to document the last stages of development, hatching out as a butterfly, but we will have to wait a week or two for that. Meantime our caterpillars, now inside a chrysalis are undergoing an amazing metamorphosis, where tissue is absorbed & reassembled, the fat stored by all that eating supplies the food & basic building blocks. The next external signs we’ll have will be the wing colours showing through a day or two before hatching… this space.

Part 2 of the story, its now mid April & our pupae are starting to hatch, more by luck than good management, we managed to watch a butterfly emerge this morning, it all happened in a couple of minutes, although it was some while later that the wings were fully expanded. You’ll notice in the first 2 pics, the difference in shape at the top of the chrysalis, the defined ridges are a sign that emergence is going to happen very soon.