“I found some!” my friend Maureen called out. I glanced over to where she was squatting by a common milkweed plant and asked, “How many?”
“Three!” she replied. A jackpot.
We were in a field alongside the Erie Canal last summer, searching for one thing: eggs from monarch butterflies. You might think that taking them from the wild would have an adverse effect on the butterfly population, but according to our research, less than 10 percent – some say less than 5 percent – manage to become adult monarch butterflies in the wild.
We collected the egg-laden leaves from the milkweed plant and headed home.
Our butterfly-raising adventure actually began the summer before. We had sent away for a kit of caterpillars, or “cats” as they are called by those who raise them, and bought other necessary supplies as suggested. Unfortunately, the project was a disaster. We somehow lost several cats, and several more died. We were disappointed to say the least!
Lessons learned and all that, we were determined to try again the following year. We spent copious amounts of time researching how to raise monarchs, and discovered our best sources on Facebook and YouTube. Helpful websites included monarchprogram.org, monarchwatch.org and texasbutterflyranch.com. We were ready when the time came.
Once we were home, Maureen carefully snipped out three small pieces of the leaf, each with an egg on it, and placed them on a paper towel on the bottom of our egg hatchery (nothing more than a small 10-gallon tank normally used for reptiles). We waited for them to hatch; four to seven days, more or less.
When they were about to hatch, the top of the eggs turned dark, almost black. If the entire egg turns black there is something wrong.
Maureen was the first to notice they had hatched. Monarch larvae are tiny things when they first emerge, just 2.5 mm or 1/10 of an inch. Miss Eagle-eye transferred the small leaf pieces, each with a larva on it, onto fresh, full-size milkweed leaves.
Larvae feed exclusively on milkweed, which contains cardiac glycosides. These compounds become concentrated in their bodies, making the larvae distasteful and potentially toxic to predators.
In Upstate New York, there are three commonly found milkweeds: common milkweed (Asclepias syriaca), butterfly weed (A. tuberosa) and swamp milkweed (A. incarnata). Many people confuse milkweed with dogbane, and monarchs will not eat dogbane! Here are three ways we use to tell the difference.
1. Dogbane tends to branch toward the top of the plant. Milkweed (with the exception of butterfly weed) will not.
2. Dogbane flowers form in flat clusters. Milkweed flowers form in roundish clusters.
3. The stems of dogbane tend to be smooth. Milkweed stems are hairy.
It is during the larva stage that monarch butterflies do all of their growing. They begin by eating their eggshell for nutrients, and then start to eat the leaf it is laid upon. This is the first “instar” or stage, out of five instars total. After they munch for a while, the larva will get too large for its skin. It will stop and molt.
During the stages, monarchs will grow from 2 to 6 mm up to 24-45 mm. Once the larvae reach the third instar, we switched from milkweed leaves to whole plant cuttings in a larger enclosure.
As the progress through their five instars, monarchs grow from approximately, 2-6mm all the way up to 25-45mm. By the time it reaches the fifth instar, the caterpillar is nice and plump with beautiful velvety-looking black, yellow and white striping.
It is estimated that a single monarch caterpillar needs around 20 entire leaves to grow large enough to successfully pupate, according to Cornell YardMap (content.yardmap.org).
Tips: milkweed cuttings work best
- Make sure you have plenty of milkweed cuttings or plants on hand. Two or three caterpillars will devour a plant in no time!
- Make sure that the milkweed is chemical free. Feeding caterpillars with milkweed that has been sprayed with a systemic pesticide will kill them in short order.
- Examine the cuttings carefully to make sure there are no eggs on them, and then wash them.
- Cut them to fit your containers.
- Clean the milky sap that accumulates on the ends by running them under warm water.
- Place the stem of the cuttings in small bottles or jars weighed down with small rocks or marbles to keep them from tipping. Fill with water. This will ensure that the cuttings won’t wilt too soon. You want fresh leaves for the caterpillars to munch on!
- Cover the mouth of the container with foil, plastic wrap or duct tape to prevent the caterpillars from crawling inside and drowning.
- Check on cuttings several hours later. If they are starting to wilt, cut the stem again.
- Leaves will keep longer if the stem is wrapped in a moist cotton ball and then covered in tin foil or plastic wrap.
- Periodically empty the containers of frass (larva poop) to prevent disease.
Larvae are ready to pupate at the fifth instar. They crawl to the top of their container and attach themselves to it with silken thread, and then hang there in a “J” shape for awhile. You can tell they are getting ready to shed their skin when their tentacles hang very limply and their bodies straighten out a bit. Then, the process of forming the chrysalis begins. It results in a fanciful, jade-colored jewel flecked with gold and trimmed in black.
The chrysalis must hang freely for the butterfly to form properly, so make sure it is not pressed up against anything. If it is, you can move it – just wait until the chrysalis is hard and dry. Maureen did it by holding onto the chrysalis stalk, called the cremaster, with tweezers. Then she carefully teased away the silk where it was attached to the container. With the silk still attached to the chrysalis, she used a clothespin to hang it in a new spot, out of direct sunlight.
Tips: be a good caretaker
Female monarchs begin laying eggs right after their first mating. Adults in the summer live from two to five weeks, giving you time to find more eggs and raise a new batch of butterflies.
The last generation, which emerges in late summer/early fall, will migrate to the overwintering grounds in central Mexico (eastern monarchs). These adults can live up to eight or nine months before heading north again.
If you want to tag that last generation to see if any make it to Mexico, check out monarchwatch.org for tagging kits. Tagging is easy and will not harm the butterfly.
You can help monarch butterflies by planting a habitat garden for them. Planting milkweeds native to your area provides a food source for larva and a source of nectar for the adults. Check out monarchwatch.org/milkweed/market to find milkweed plants or seeds.
Various predators attack monarch butterfly eggs and either eat them or parasitize them, despite the taste. They include ants, paper wasps, leaf-rolling spiders, assassin bugs (employed by farmers to keep their crops caterpillar free) and some birds. It’s a wonder that any monarchs survive to adulthood!
An adult emerges in 10 to 14 days. When it is ready to emerge, the orange and black wings become visible through the pupa covering. Finally, all your work and patience have paid off as a gorgeous Monarch butterfly ecloses (emerges) from the chrysalis. It takes several hours for the wings to harden, so don’t release them until then. They do not need to feed for 24 hours.
If you plan on keeping them for awhile, experts recommend fresh-cut slices of oranges, watermelon or nectarine; honey water (one part honey to nine parts water); non-red colored Gatorade or Juicy Juice.
The butterfly’s feet and abdomen must remain dry, so for a feeding station, we placed a plastic, chemical-free pot scrubber into a small, shallow container.
Male and female monarchs can be distinguished easily: males have a black spot on a vein on each hind wing that is not present on the female.
You can help Monarchs by planting a habitat garden for them. Planting milkweeds native to your area helps in several ways; as a food source for larva and as a source of nectar for the adults.
To see more Milkweed plants or seeds, check out Monarch Watch’s website: monarchwatch.org/milkweed/market
Story and photos by Phillip Bonn