Monarch Butterfly Migration Update: April 15, 2005
Today's Report Includes:
- Latest Migration Map and Data
- News From Along the Migration Trail
- Comparing Migration Maps: Spring 2002, 2003, and 2004
- Expecting Monarchs in Arkansas: News from the Nursery
- Needs From the Breeding Habitat: Food, Water, Shelter, and Space
- How is Habitat Like a Good Parent? Discussion of CQ #12
- Adaptations that Help Monarch Young to Survive
- A Look at the Life of a Monarch Caterpillar
- How Much Would You Weigh? Challenge Question #13
Latest Migration Map and Data
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News From Along the Migration Trail
The migration pushed on last week, with early monarchs arriving as far north as Missouri and Kansas. The latitude of this week’s northernmost sighting is 39 N, surpassing last week's 35 N. How many miles farther north is that? With not a single report from South Carolina, the migration appears to be missing that state. Why might that be the wrong conclusion?
In the west, the map shows a sighting from Arizona. Chris Kline, of Arizona's Boyce Thompson Arboretum, says many monarchs are counted during the fall migration, but they are conspicuously absent in spring. Did this monarch come from Mexico or from California? "I don't know what's going on with monarchs in Arizona," Chris said. "We haven't collected anywhere near enough data, but the two fall tagged migrants that were recovered were both heading in a southerly direction."
For those counting states and provinces where monarchs have arrived, you can add five new states to your list, thanks to five single butterflies in Tennessee, North Carolina, Missouri, Kansas, and Arizona:
Comparing
Migration Maps: Spring 2002, 2003, and 2004
How does this spring's migration compare to those in previous years? How
are they similar, and how are they different?
| 2004 As of April 14 |
2003 As of April 11 |
2002 As of April 11 |
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Expecting Monarchs in Arkansas: News from the Nursery
Female monarchs have been laying eggs across the map. Ms. Monarch, still captive in Arkansas, illustrates the magnitude of their effort:
In just two weeks she has laid a grand total of 504 eggs! She has not produced any more since Sunday, April 10, but is still alive. "I believe she is finished with her egg laying," reports Dr. Edson. "I have caterpillars hatching out all over the place." The 93 eggs Ms. Monarch laid on April 3rd began to hatch on April 8th. How long did the monarchs remain as eggs? What do you notice about monarch eggs, before and after hatching? Here is Dr. Edson's daily journal:
| How did the eggs change? | ||
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| Last Week |
This Week | Close-up |
Needs From the Breeding Habitat: Food, Water, Shelter, and Space
After hearing that one monarch can lay 504 eggs, is there anything you want to your list of habitat needs? Add to this chart as the season continues.
How is Habitat Like a Good Parent? Discussion of CQ #12
Mother monarchs don't care for their young, they let Mother Nature do the job. "Well, if you think about it, it's not that bad," began Brandy in Arkansas. "The mothers lay their eggs on milkweed so they have food."
How do young monarchs survive on their own? Good habitat and the monarch's unique adaptations are opposite sides of the same survival coin.
Adaptations that Help Monarch Young to Survive
An "adaptation" is a physical or behavioral feature an organism has that evolved in response to pressures for survival. How a species looks, moves, obtains food, reproduces, and responds to danger are examples of adaptations. We'll follow the theme of "adaptations" as the season continues.
A young monarch has many adaptations for survival. Today, read about monarch eggs and larvae, and explore their adaptations. Remember: There is always a WHY behind WHAT you see. So whenever you see an unusual behavior or body part, ask yourself WHY. Here's a chart for recording the adaptations you discover this season:
- Adaptations that Help Monarch Young to Survive
- A Look at the Life of a Monarch Caterpillar
- A Day in the Life of a Butterfly Egg
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| Eggs
are usually laid on the underside of the leaf. |
The
day before hatching, the top of the egg turns black. |
Immediately after emerging, the monarch turns back and eats its own shell. |
How Much Would You Weigh? Challenge Question #13
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Can you find the two larvae in this picture? (Click to enlarge.) |
The moment a monarch hatches from its egg it begins to eat. The first thing it eats is its very own shell! Monarchs spend the larval stage of their lives eating--and growing. In fact, the typical monarch increases in mass by 2,000 times while it's a caterpillar. This amazing change takes place in only about 9-14 days. Can you find the two larvae in the picture to the right? They are shown at the beginning and end stages of growth. Imagine gaining weight the way monarch larvae do:
Challenge Question #13
"How much would you weigh if your weight increased 2,000 times? With
your answer, name something that weighs the same amount."
How to Respond to Today's Monarch Challenge Question
1. Address an e-mail message to: jn-challenge-monarch@learner.org
2. In the Subject Line of your message write: Challenge Question #13
3. In the body of your message, answer the question above.
The Next Monarch Migration Update Will Be Posted on April 22, 2005
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