Insects - Monarch Butterflies

Insects - Monarch Butterflies The regal orange and black monarch butterfly is one of nature's marvels. It is famous for its beauty and especially for its travels.

Monarchs, like many birds, fly south for the winter. Some travel as far as 2000 miles to warm wintering grounds. Their migration begins in August or September. They travel by day and stop occasionally, every few days, to feed. They often travel as far as 80 miles in a single day. They follow the same routes and land in the same areas as millions and millions of monarchs before them even though most of them never made the trip before.

Monarchs from the western part of North America gather in California along the Pacific coast and in central Mexico. Monarchs from eastern North America gather in Mexico as well as parts of Florida and Texas. Once at their wintering grounds, they gather in trees and hang in huge clusters that may contain hundreds of butterflies. They do this to keep warm, and they only leave the trees to feed. When spring arrives, some mate and then begin their journey back north. Others begin their journey and mate along the way. They lay their eggs on milkweed plants on their way home. Most do not live long enough to make it all the way back to their starting point. The eggs laid along the way hatch, and those young butterflies continue the flight back north to the homeplace of their parents. Through the summer, they mate and lay eggs as well. It usually takes 2-3 generations of monarch butterflies to complete the migration cycle. It is the children or grandchildren of the butterflies in Mexico or California that return there the next winter.

Danaus Plexippus : Monarch Butterflies

The predators of monarchs are shrews, moles, and other small mammals as well as birds. However, monarch butterflies taste BAD. They can be poisonous to a bird if it eats too many of them. A bird will usually become sick even it it eats only one butterfly. Birds learn that orange and black butterflies are bad for their health and well-being and avoid them. This bad taste and toxicity comes from the milkweed plants that monarchs eat as caterpillars.

Monarch larvae feed almost exclusively on one kind of plant. What is it?
What do adult monarchs feed on?
How long do monarch larvae (caterpillars) stay in their chrysalises?
What are the economic benefits to humans of monarch butterflies?

Coloring Page on Monarch Life Cycle

Monarch caterpillars have yellow, black, and white stripes.

Butterflies undergo complete metamorphosis. This means that there are four separate stages of development, each of which looks completely different and serves a different purpose in the life of the butterfly.
Describe what the monarch butterfly looks like at each stage.

Monarch Photo

Monarch butterflies emerge from their chrysalises on warm, sunny days because they need warmth to be active. Once they emerge, it takes about 20-30 minutes before their wings are dry, plumped up, hardened, and ready to fly.

Look at this photo of an adult monarch butterfly. Why do you think it is called a monarch?
What is a monarch? (If you don't know what a monarch is, look it up: Webster's Dictionary)

Monarch Eggs

Monarch butteflies lay only 1 egg per milkweed plant so that there will be plenty of food for the caterpillar which will hatch from the egg. Female monarchs lay about 400 eggs on 400 different milkweed plants.

What purpose does the layer of wax on a monarch egg serve? (Doesn't that closeup picture of a monarch egg kind of look like an alien spacecraft?)

Monarch Caterpillar

Newborn monarch caterpillars are only about 1/8 of an inch long! However, they have a huge appetite. First they eat their own egg shell. They they begin to eat the milkweed plant where they live. They pretty much eat nonstop--night and day. Large monarch caterpillars can eat an entire milkweed leaf in less than 4 minutes! In about 2 weeks, a monarch caterpillar will be full-grown and will be about 2 inches long. It will have gained about 2700 times its original weight.

How does the caterpillar's antennae help it?
How do the tiny hooks on the caterpillar's legs help it?
How do caterpillars breathe?

Monarch Chrysalis

When it is time to form a chrysallis, a monarch caterpillar uses a special gland in its mouth to weave a small silken circle. It places this underneath a leaf or small branch. The caterpillar thhen hooks small claspers on the rear of its body onto the silken circle and swings around to let its head hang down. Then it wiggles and wiggles back and forth until its kin splits open and it wiggles more until it sheds its skin. What emerges is the chrysalis. It is about 2 inches long and is light gren and soft. Soon the outer layer hardens and turns darker green and gold.

When the caterpillar is about to make its chrysalis, it sheds its exoskeleton.
About how long does it take for the caterpillar to make a chrysalis?

Tagging Photo

Adult monarchs feed on the nectar of flowers. They prefer the nectar from milkweed flowers. However, if none are around, they will feed on the nectar from other flowers.

To track monarch migration, entomologists (scientists who study insects) tag adult monarchs. This photo shows the small numbers that have been attached to the wings of these butterflies for tracking purposes. If the butterfly is tagged in Vermont, where do you suspect that scientists might find this same butterfly in the wintertime?

Milkweed

Monarch eggs are light yellowish-green and blend in with the color of milkweed plants. About 4-7 days after a monarch egg is laid, the caterpillar hatches and begins to munch on the milkweed plant.

Monarch caterpillars almost exclusively eat only milkweed plants. However, how many different species of milkweed are there?

Teacher Resources

Monarch Watch is the ultimate page for teachers who need monarch butterfly information. You can order larvae, rearing kits, teeshirts, etc. There is information on how to grow your own milkweek for monarchs. You can find classroom activities that teachers around the US are participating in. You can find out about how monarch migration is being tracked, information on how to plant a butterfly garden in your schoolyard, and much more.

SURWEB is a great resource for teachers. It a tool (developed in Utah!) that allows teachers and students to make their own miltimedia presentations. SURWEB has a database of over 12,000 photographs that can be used to make slide shows. You can view public slide shows that others have already been created or make your own. As it relates to insects, there are many photos of Utah insects that can be used in classrooms. Check out the Butterflies of Utah page that lists the butterfly photos that your or your students can use to make presentations. At the bottom of that page are a list of media shows that have already been made with the images. Butterflies of Utah - Family Papilionidae - The Swallowtails is an example of one of the presentations. Native Utah Insects and Insects of Utah list photos of other Utah insects that you can use. Spend some time and check out the other resources SURWEB. It is a wonderuful source for content, particularly for 4th and 7th grade teachers, as well as a useful tool for making presentations.

The Journey North (South) is an incredible (and fun and easy) way for students to be engaged in a global study of wildlife migration and seasonal change. The journeys of a dozen migratory species are tracked each spring. "Students share their own field observations with classrooms across the Hemisphere. In addition, students are linked with scientists who provide their expertise directly to the classroom. Several migrations are tracked by satellite telemetry, providing live coverage of individual animals as they migrate. As the spring season sweeps across the Hemisphere, students note changes in daylight, temperatures, & all living things as the food chain comes back to life."

Classrooms simply sign up to belong to the Journey North email-based mailing list. As it relates to insects, if students observe monarch butterfly movement in their area, they post that information to the mailing list. Classrooms don't even have to post their own information to benefit from this project. Just reading the email postings from other areas of the world is fascinating. Or if email access is a problem, classrooms can read a digest of each day's news directly from the Journey North page. There are teacher tips on how other classrooms are integrating Journey North into their curriculum, classroom lesson plans, and a teacher discussion page. Tracking the migration of certain species of whales is a particularly interesting part of this project as well as different kinds of birds. Don't miss the "Signs of Spring" portion of this project. Your class can plant tulip bulbs in the fall and track their growth in the spring with other classrooms in the U.S. This is an easy way to particpate in an internet project and is such an engaged, interesting, and fun way for students to begin to grasp the the global nature of the internet as well as feel connected to students around the world. Journey North is educational internet at its best.

Bibliography

Orem, Liz and Baker, Robin. Insect Migration. Steck Vaughn : Austin, Texas, 1992.

Still, John. Amazing Butterflies & Moths. Knopf: New York, 1991.

Author: LINDA MOSBACKER - Email linda.mosbacker@slc.k12.ut.us