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Monarch Life Cycle

Madame Monarch flits through the garden examining leaf after leaf. "No, that's not it...no, not that one, either. I know it’s here, somewhere. Ah, there it is!" She flutters her wings over the leaf and scratches it with her little hooked tarsi to release some of the plant's volitile scent. Now she's sure it's the asclepia or milkweed she's been looking for. She grips the leaf with her little hooked feet, curls her abdomen under and deposits one tiny turban-shaped egg on the underside of the leaf. She flies away briefly and returns to deposit another egg, again and again.

You’ve just witnessed the beginning of a new lifecycle and if you're diligent, you may find you're privy to one of Nature's wonderments. Next time you take a walk, take a moment to examine a milkweed. Usually deposited on the underside of the leaf, the monarch egg is about the size of a grain of sand. Examined under a lens, it has a point and ribbed sides. After four to six days, the larva will hatch from the egg, eat the shell and proceed to nibble on the milkweed leaves. Monarch larva are tough to find against the veining of the milkweed leaf. An easy way to know if there are monarch larvae feeding on a plant is to look for the "frass" or little larval poop. When you find the frass, check the leaf just above it and you'll likely find the larva.

The larva will shed its skin up to five times in this period, each of those times is called an "instar". A first or second instar larva is young; a fourth or fifth instar larva is just about ready to begin the next phase of development, or the pupal stage.

Monarch larvae remain in this stage for two to three weeks. During this time, they will increase in size from nearly invisible to nearly three inches. The larva will shed its skin up to five times in this period, each of those times is called an "instar". A first or second instar larva is young; a fourth or fifth instar larva is just about ready to begin the next phase of development, or the pupal stage.

When it's time for the pupal stage, the larva will almost always leave the host plant and hustle off to find a quiet, protected place to "hang out", which is literally what they do. The larva selects the location where it will hang inside its chrysalis skin for nearly two weeks. Grasping with its two hindmost feet, the larva will hang on a silk pad it deposits, slightly curled or in a "prepupal" shape for nearly 24 hours. If you've been watchful up to this point, be sure to have a video camera ready. Usually very early in the morning, the larva will relax and hang straight, then start to undulate. In a matter to about two minutes, the old striped larva skin will split, a small hooked device called a cremaster will slip out, slice off the skin and hook on to the silk pad, and there hangs the chrysalis, jade green with lovely gold dots. The pupa wriggles and twists for about an hour until the "shell" hardens. Mark your calender, for the next amazing event will happen in about 14 days.

Grasping with its two hindmost feet, the larva will hang on a silk pad it deposits, slightly curled or in a "prepupal" shape for nearly 24 hours.

During this time, the larva's cell structure breaks down into what one author refers to as a "cellular soup". Small clusters of cells, called imaginal buds direct the amorphous cells to form head, thorax, abdomon, wings, legs, and all the rest of those parts that compose an adult monarch.

The day before the monarch is ready to hatch, the jade colored chrysalis will begin to darken. It will begin at the bottom changing from green to grey to black, or what appears to be black. Look closer and you will begin to see orange and black and all those marvelous white polkadots the adults sport on their fuzzy bodies. Stand by with your video camera.

	Chrysalis stage 1: Green Chrysalis
Chrysalis stage 2: Dark Chrysalis
	Chrysalis stage 3: Emerging butterfly from clear chrysalis shell The actual hatching happens very quickly. The "seam" along the back of the chrysalis rips and the adult monarch immediately emerges and clings with those tiny hooked tarsi, feet, to the chrysalis shell.
Monarch with teensy wings and huge abdomen hanging under a coneflower

Just moments before the adult is ready to emerge, it will draw air into the chrysalis through spiracles, or breathing holes. This seems to accomplish two things: 1) the air helps separate the monarch’s body from the inner lining of the chrysalis, and 2) helps split the chrysalis shell along the back so the adult can emerge. (This author has been treated to this event, three times recently, all of which happened close to noon on a sunny day.)

The actual hatching happens very quickly. The "seam" along the back of the chrysalis rips and the adult monarch immediately emerges and clings with those tiny hooked tarsi, feet, to the chrysalis shell. At this point the wings are crumpled, wet and very tiny whereas the abdomen is swollen with fluid which, over the next hour or so, is pumped into the wing veins. While the young adult is hanging, you might check to see whether it is a male or female. Males have a black dot on each of the hindwings.

After resting and drying for several hours, the young adult butterfly will likely venture out and explore your garden. Adults live from one to three months and have two tasks awaiting them; to find nectar-bearing flowers, and to find a mate. Those black dots on the male are scent glands and he will use them to impress eligible females in the area. Once she's been...impressed, the female begins her search for just the right plant on which to lay her eggs.

"Now I know it's here somewhere...No, that’s not it. Ah, yes, this is the one... milkweed... Ahhhhhhh!" and the cycle begins again.

While the young adult is hanging, you might check to see whether it is a male or female. Males have a black dot on each of the hindwings.

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