Winter Monarchs: Update and a Backgrounder

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By Bob Pish
Photos by the author

Note: This continues Bob's fascinating post on observing Monarch butterfly development from yesterday, available here.

The Monarch Experiment: Update 21 December
Well several changes have been happening to the Fourth and Second Hatch caterpillars.

Last night the caterpillar that had traveled to the top with the one that formed a chrysalis/cocoon was back feeding. He/she/it is in the foreground of the picture below. It continues to amaze me how fast they can strip a leaf. In the background is the Second Hatch caterpillar that had adopted the bottom of a leaf for his/her/its conversion process and about an hour later was inside his/her/its chrysalis.

The feeding caterpillar was especially active yesterday and traveled up to the top of the house at least once and then back down to where it was in this picture but it has also moved around quite a bit from plant to plant. May have to name him/her/it Traveling Sam.

Unfortunately, Wrong Way spent all day on his perch on the side of the box. Very little movement. This morning I decided to give him a chance to get some food and again moved him back onto a plant. When I lifted him off the wall, he had a silky thread running from him back to his favorite clump of dirt.  Things are not looking too good for Wrong Way.

And in another area, the first of the second hatch crew, the one that formed a chrysalis two days ago has two thin lines of silk coming out the bottom of the cocoon with what looks like a drop of moisture at the bottom end.

Its location in the Monarch House made it hard to photograph so it is not in as sharp a focus as I would have liked but I tried quite a few times and this was the best of them. As I moved the front bay window to get a better shot, the two threads intertwined. The discoloration at the top does not look promising either although it is not as obvious when you look at it.

And a final observation for the morning is that all of the other “chrysalis-es” – “chrysales”- “chrysali” (whichever is the plural) today have two of the gem-like dots near the bottom on the side opposite the upper dots. These dots seem to reflect light like the ones found on the upper circumference giving them the “Gem-like” appearance. I will try to get a picture later.

Background Information:
In a rather amazing natural cycle, three generations of Monarchs are born and die in a northward migration following the emergence of more milkweed plants further north. Then in a rather miraculous way probably triggered by weather, day/night patterns, stars, or cell phones and GPS, the fourth generation heads to Central Mexico or Southern California. Not only that but they spend the winter there and fly back to Texas [at least the ones in Mexico] in the spring as the milkweed blooms. Each of the first three generations live maybe two months and every fourth generation not only lives six months but travels thousands of miles.


A Single Butterfly’s life cycle:
Three Generations Have this life span. Every fourth generation lives as explained in Sept/Oct below

The total time frame for one butterfly's life cycle (one generation) is about six to eight weeks . . . egg, caterpillar, chrysalis, butterfly.

It grows inside the egg for about four days.

It then munches milkweed and grows as a monarch caterpillar (larvae) for about two more weeks.

The caterpillar's life inside the chrysalis (pupa) lasts about ten days and

its wonderful life as an adult butterfly lasts from two to six weeks.

The Monarch Migration Cycle
- hibernating monarchs in Mexico and southern California reawaken, become active, find a mate, begin the flight northward and lay their eggs. Finally they die. These special monarchs have lived about four to five months through the long winter.

March/April -the first generation monarchs are born -egg, caterpillar, chrysalis, adult butterfly;

May/June - the second generation is born - egg, caterpillar, chrysalis, adult butterfly;

July/August - the third generation is born - egg, caterpillar, chrysalis, adult butterfly;

Sept/Oct - the fourth generation is born - egg, caterpillar, chrysalis, adult butterfly . . . but THIS generation does not die. It MIGRATES south and lives six to eight months in Mexico or Southern California. They begin awakening and mating in February/March of the NEXT SPRING, and then lay their eggs! Withered and tattered from their migration and hibernation . . . they finally die.

Other Stuff
The caterpillar's "skin" or cuticle is like a shell - it does not grow. As the caterpillar body grows bigger and bigger, it outgrows its skin and needs to SHED it. The caterpillar squeeeeezes, pushes and tugs as it wiggles out of its tight old skin.

Then it rubs off its FACE MASK. Even the face mask has become too small. The most amazing part is when the caterpillar turns around and EATS its own skin. Just like the eggshell that it ate for breakfast, the old skin is filled with vitamins to help our caterpillar grow big and strong.

After the fifth and final skin shed, the monarch goes into its next stage of life. Through an amazing metamorphosis - a total body CHANGE - the caterpillar transforms into a beautiful green chrysalis.

This site has a brief nine step video of the process of going from a caterpillar hanging onto a silk button to the inside of a crysalis.

View the Emerging sequence on:

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One Response to Winter Monarchs: Update and a Backgrounder

  1. Thanks for the updates on this fascinating story. Monarch experts need to know about this.

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