THE NATURALIST PAGE:

     This is a collection of pages on various naturalist subjects. The collection will be added-to with time. Any suggestions for subjects or improvements to the site may be e-mailed to me and are welcome.

     This is a "recipe" for the rearing of Monarch Butterflies (Danaus plexippus) that I devised back in 1962 when I raised and released about a dozen Monarchs.

     Be aware that everything this creature does, at this period in its development, is done for the first and last time. There is no training period; nor margin of error allowed. It's either success or death and some of the things the creature accomplishes are really remarkable! I guess that is why I have been able to remember most of the details over the years (there may be a few lapses of memory, however!).

     The exercise started in mid-July, 1962

     Equipment: Nothing special except you may need something resembling an old aquarium or terrarium as will be explained later.

     Find a milkweed patch. You need same to provide a supply of fresh fodder for the caterpillar as the exercise progresses.

     Examine the undersides of some of the leaves of the milkweed plants for eggs. They are very small (less than 1 mm.), light green in colour, somewhat football-shaped. If you're really lucky you may encounter a female monarch laying them.

     When you find an egg (s), cut off the milkweed stalk (about 1 foot) and stand it in a bottle of water to provide some continuing moisture to keep the primary leaf as fresh as possible. I don't recall how long it takes for the eggs to hatch. Try to collect a number of eggs for insurance.

     The egg will hatch into a very small white, black, and yellow circumferencially - striped (partially) caterpillar that, after eating the remnants of the eggshell, begins feeding on the "fuzz" that is on the surface of the leaf.

© Science Museum of Minnesota

     Because the caterpillar eats on a " 'round-the-clock" schedule, you will find that it grows in size fairly quickly. As it grows it quickly graduates from fuzz-eating to devouring the leaf structure in a very mechanized manner. This is where access to a milkweed patch is important. As the primary stalk and leaves begin to dry out it will be necessary to get a fresh stalk and "coax" the caterpillar to transfer over to a fresh leaf on the new stalk. A stalk, as opposed to just single leaves, is important, as the moisture in the stalk supplies the leaves and helps to keep them fresh. Leaves on their own will dry out very quickly. You will also need a pan to catch the droppings (dry) that are produced by the caterpillar. A pan of water as a "moat" may be useful in preventing the caterpillar from wandering away as time passes.

     The caterpillar will continue to eat and grow until it is about 2" long. It is sensitive to sound. Snap your fingers and you should see it flinch.

     When the caterpillar is fully grown, it stops eating and becomes very restless, developing a tendency to wander, looking for a suitable place for the next stage. This is where your ingenuity comes in. You may need something like a terrarium to keep it confined. It will be looking for the underside of a horizontal surface such as a milkweed branch or other stick.

     After some wandering (and I don't think that can be avoided - the wandering period seems to be a requirement even if constrained to one collection of plant branches) the caterpillar settles down and begins to spin a "rosette" of silk from its mouth, onto the chosen site, until the appropriate size of rosette is reached, or possibly, a programmed time has elapsed.

     Upon completing the silk rosette with its mouth, the caterpillar then crawls over the rosette and grasps it using the rear part of its caterpillar body, while still holding on to the stick with its forward feet.

     In about two hours, the caterpillar releases its hold on the stick and hangs downward while still grasping the rosette with the rear section of its body. The caterpillar hangs this way, in a slight "U"shape for about 14 hours while various internal changes take place.

© Dale A. McClung

     The next step is really remarkable: While still holding onto the rosette with its rear end, the caterpillar's skin begins to split at its head to reveal a sightless, legless, creature. A "rear tailhook" (called the "cremanser") appears and is blindly manipulated to reach around, hook onto the rosette, and become the creature's sole means of suspension. At the same instant the old skin drops away; the legless creature compresses its length as if it had an internal spring; and voila! - we have the beautiful, light-green, hard chrysalis with its crown of gold dots, hanging from the rosette! In the photograph, note how small the point of suspension is!

     The chrysalis stage lasts about 12 days during which the shell gradually becomes transparent to reveal the developing butterfly within. At the end of this stage the butterfly emerges, "pumps up" and unfolds its wings, rests a while, and then takes flight.

© Dale A. McClung

     In carrying out this exercise I usually placed the set-up by a screened window that the butterfly could fly and cling to. Finally the window would be opened for release While the butterfly is clinging to the screen it can be fed a bit of water/sugar solution from an eye dropper.

     Now the key to get the butterfly to drink the sweet solution with its coiled up tongue is that Its sense of taste is not in its mouth, but in the "knees" of its forelegs! Touch the sweet liquid to one and its tongue will immediately uncoil, search out the liquid and drink it up. After feeding it as much as it wanted, I would then open the screen and release it.

     This essentially concludes my recipe for rearing Monarchs. For further information especially on the amazing migration characteristics of this creature check out the reference links provided.