9/25/14

Volunteers to Raise Monarch Butterflies for Schools

.
Volunteers needed!

The monarch's numbers are in steep decline--we can't save them unless children know about their amazing metamorphosis and migrations!

A butterfly ranch in my kitchen ->

So the Friends of Lake Wingra has a program to raise Monarch Butterflies for schools.

We've worked out a method, delivering 13 large caterpillars and chrysalises to Thoreau Elementary School.  With your help, we can supply more classes.

The second grade classes at Thoreau School were very excited.  Rapt with attention, the kids asked many smart questions.  Some of the kids are already experienced raising unusual pets--and a number of them begged me to give them monarch eggs.  One gave me a "thank you" hug when we were done.

Here's what's involved.  You can participate in the whole process, or just one of step.  We can train you.  Contact David Thompson at 233-9589.

Finding eggs

This is the hardest step.  In Madison, WI, you can find eggs from May through September.  Find eggs about 4 weeks before they are needed--finding eggs in August and September is ideal for fall classes.

Adults nectaring at a botanical garden.
When you find many adults, they may be laying nearby.
Click on photos to enlarge.

Find a large garden where many monarch adults are feeding.  Then locate a milkweed plant.  That's any plant in the genus Asclepias, such as common milkweed, butterfly weed, or marsh milkweed.  Look for eggs on the food plants not far from where the adults are nectaring.

The eggs are about the size of the head of a pin. They are very distinctive--round, ridged, and colored from white to light cream to yellow.  At first, you may confuse the eggs with tiny droplets of coagulated sap on the common milkweed, but these sap droplets are less regular and not so yellowish.

The eggs tend to be located on the top half of the plant.

Usually there is only one egg per plant, but I have  found up to 4 eggs per leaf, and 6 eggs per plant.

 The eggs are nearly always attached on the underside of leaves, but you may find them on top, or on unripe seed pods (September).  It may help to bring a magnifying glass.  Eggs are

If you are looking in a garden, your best bet may be to think like a Monarch: What is the most conspicuous and easily reached food plant from where you are nectaring?  This may be near the top of a plant, perhaps on a plant hanging conspicuously over a pathway.   If you find one egg, look for more on nearby food plants or similar locations.

Another method is to wait in a garden and look for females laying eggs.   It takes just a few seconds to lay an egg; she curls the end of her abdomen under a leaf to place the egg. They are laying eggs if they are flitting from plant to plant, but not always landing on the flowers. She may alternate between nectaring and laying eggs.  You might carry some marking tape, to mark where she may have laid an egg as you follow her about, so you can come back later to collect them.

 Mating pair: The male (wilh wings spread) shows a dark spot on each hind wing; the females have no spot.


Another strategy is to simply examine food plants, looking for eggs--but only if you have seen monarchs in the area.  When I tried this approach in May, I had to examine about 20 common milkweeds for each egg I found.

When you find an egg, you can tear off part of the leaf, and place it gently in a loose chest pocket until you get home.  The eggs are somewhat sturdy and don't fall off the leaf.  Keeping them in your pocket assures you won't leave them in a hot car--yikes!

Keep a magnifying glass and small container for eggs in your car, in case you pass a garden or see monarchs.

Here's a method I haven't tried that could be very productive.  If you observe a female laying eggs, catch her with a butterfly net and place her in a mesh enclosure with a large milkweed cutting.  She will lay many eggs on the plant.

Hatching the egg

For raising small caterpillars, I use small, transparent plastic containers with lids.  For example, Trader Joe's cookie containers, or date containers.  You might try the salad containers you get at the salad bar.  Puncture a large number of small air holes in the lid.

Using scissors, cut a small square of leaf with the egg in the middle, and transfer it to a plastic box, egg side up, using tweezers.  I arrange up to 20 eggs in rows in the box.  Then, several times a day, I can scan down the row of leaf squares, using a flashlight to aid my vision, and look for newly hatched caterpillars.  They are very tiny!  The eggs take 5 days to hatch.  Chances are, you found a freshly laid egg. (Eggs don't seem to last long in the wild before they are eaten.)

When you find a caterpillar, transfer it with a very fine watercolor brush (right) to a fresh leaf in a new plastic box (also with holes in the lid.)  You can put 5-10 first instar caterpillars on one leaf, since they don't eat much at first.  Be very gentile.  Try lifting the caterpillar by its rear end first--they spin a strand of silk, and this may attach to your brush.

Feeding the small caterpillars

Since the tiny caterpillars don't eat much at first, your challenge is keeping the food leaves from drying out.  You could change the leaves often, but then it's time consuming transferring the tiny caterpillars to the new leaves.  What I did was to place a small wad of paper towel around the stalk of the leaf, held on with a twistie or small rubber band.  I kept the wad wet with drops of water several times a day.  This extended the life of the leaf to 2 or 3 days.  They prefer smaller, younger leaves, especially when the caterpillars are small.

If the leaves dry out, the caterpillars won't get enough water with their food.  That's one reason I leave a top on my caterpillar boxes--to keep the humidity high.  If you suspect dryness is a problem, you can mist the leaf once or twice a day while they are feeding.  I have seen them apparently drinking water from droplets.  But you don't want to encourage growth of mold.

I place a twig under each leaf, to give the caterpillars room to get under the leaf, where they like to hide while eating.

Every time you add a new leaf, clean out the frazz (excrement pellets), and wash out the box.  Sanitation is important, since a few of the larvae may carry disease which could spread to the others.  (But it's not a danger to humans.)  If one caterpillar looks consistently sick or dies, quarantine it.

Keep track of how many eggs or caterpillars die.  More than 50% of my eggs lived to form a chrysalis.  About 20% of the eggs failed to hatch, perhaps because they dried out.  Some of the small caterpillars failed to grow much, and eventually died.  Sometimes larger caterpillars escape.  They may simply disappear, or you may step on them as they cross the floor.

So expect some mortality--it's very high in the wild.  But if you have high mortality, you may be feeding the wrong plant, or they are drying out, or there's a disease problem (and you need to rear them separately).

But don't confuse "illness" with dormancy.  The caterpillars will rest and become very inactive for about a day when they are preparing to molt (and just after).  Sometimes they just rest after eating a lot.  For example, they may run out of food and then you give them a new leaf.  They gorge on the new leaf for half a day, then rest for half a day.

The caterpillars often wander when preparing to molt.
 If you see them trying to climb the side of their box, or otherwise trying to "escape," it may simply be a sign they are looking for a good place to molt (or to form the chrysalis).

Or, wandering may be a sign that their food isn't right (dried out, or the wrong plant).  You can test the "thirsty" theory by misting them.

Feeding larger caterpillars

Large caterpillars can eat many leaves a day, depending on the size of the leaf.

 So if you have a number of caterpillars, it will save you a lot of time to cut an entire plant, and put it in a heavy vase with water.  Then transfer all the caterpillars to the cut plant.  Place the vase over a large piece of brown paper (with the edges bent up) to catch the frazz.  A common milkweed plant, when placed in a vase, will last 2-3 days.

Be sure you cover the vase opening with plastic wrap, holding it in place with an elastic band.  Poke a hole in the wrap, then push the milkweed's stem through the hole and into the vase.  This assures the caterpillars won't drown.

After about 2 weeks, when the caterpillars are 1.5-2" long, they are ready to form the chrysalis.  At this time, they are especially likely to wander--perhaps climbing down the stem, down the vase, and across your kitchen floor.  If you place the vase on a table, there's a good chance a wandering caterpillar will form its chrysalis under the table.  About two thirds of my caterpillars formed chrysalises in the cut food plant; the other third wandered.

Just before they form a chrysalis, they hang from under a table or leaf in a "J" shape, attached by a little pad of silk.  The "J" stage lasts 1-2 days.  Next, you transfer the "J" or chrysalis to a plastic box, in preparation for transport to the classroom.  Cut off a small piece of the leaf the chrysalis is hanging from, then tape that piece to the underside of the lid of the plastic box (away from the edges of the container--the butterfly needs space to emerge).

If the chrysalis forms on the underside of a table, you can transfer it by tying a piece of thread around the stalk of the chrysalis, then cutting the base of the stalk, so the chrysalis is now hanging from the thread.

Once in the "J" or chrysalis, there is no need to feed the monarchs any more.  But you should protect them from disturbance, direct sunlight, heat, or freezing temperatures.   Record on a sticky note when each chrysalis forms--so you can give each class several chrysalises that will emerge on different days.

The classroom


Plastic bin ready for transport to school:
Chrysalises are taped to inside the lids of individual plastic containers.
On the milkweed stalk are several "J" caterpillars.
Labels indicate when emergence is expected.

We haven't worked out firm details for classrooms yet.

When I distributed large caterpillars and chrysalises to second grade classes, the teachers wanted me to talk to the kids for 10-20 minutes, and answer their questions.

If you distribute caterpillars, this raises the issue of feeding them many leaves daily.  I am not sure that younger kids or busy teachers are up to this, or know where to get the leaves.  I have heard of previous attempts resulting in dead caterpillars or chrysalises.  I have helped the feeding process by bringing a cut common milkweed to to the school's office each day.

Probably the biggest challenge is making sure the class actually sees the adult emerge from the chrysalis.  This is the goal of the whole exercise!  I suggest that several of the more observant children be tasked with watching for when the chrysalis shell goes transparent--when you can see the orange and black wings inside.  This means the adult will emerge the following day--possibly around mid morning.

The chrysalis should be checked first thing in the morning, and several times during the day--especially after lunch.

However, it's possible the butterfly could emerge in the evening or during the weekend.  For that reason, I give each class at least three chrysalises--ones that formed on different days.

I'm wondering what's the best method for giving the class a good view of emergence.  After 3-4 hours of expanding the wings and hardening the exoskeleton, the butterfly is ready to fly off.  You don't want it to get loose in the classroom.

On the other hand, you want all the kids to be able to see CLEARLY what's happening.

Normally, the chrysalis is placed in a small flight enclosure made of mesh.  Ones made for this purpose can be purchased, or you can use some kind of dirty laundry container, or even an old aquarium.

What would be ideal would be to take the lid of the box the chrysalis is attached to, and suspend it above children's eye level with tape, out in the open, from something like a tripod or lamp stand.   This way, the children can surround the emerging butterfly and see it clearly.

The teacher has to judge when the butterfly has finished hardening its wings, and put it back in an enclosure before it flies away.  However, the overall process takes several hours, so there should be time for children to safely see the early part of emergence, CLOSE UP!

If the adult butterfly isn't released right away, it should be fed with sugar water from a small piece of sponge, or perhaps a hummingbird feeder.  I recommend immediate release if the weather is good, since we're trying to save monarchs.


Resources

There are many curriculum materials available on the web.
 Most important for schools would be either a poster on the life cycle of the monarch, or a mesh enclosure for the butterfly.

Materials for the whole process

Containers--small, transparent plastic, with lid. Enough for each caterpillar.
Access to food plants nearby
Brush, very fine, for transferring caterpillars
Tweezers
Magnifying glass, pocket (10X or more)
Small flashlight
Scissors (for cutting plant stalks, cutting leaves, or cutting squares out of leaves)
Vase (heavy, so it won't tip over with large milkweed)
Plastic wrap, rubber bands
Table for your menagerie (optional)
Mister for houseplants (optional)
Colored marking tape (optional)
Large plastic bin for transporting materials to school (optional)

No comments:

Post a Comment

Please feel free to comment on the article above, or on other watershed issues.