Expecting Monarchs in Arkansas: News from the Nursery
Observations contributed by Dr. Jim Edson

This female monarch was captured in Arkansas on March 31, 2005. She had probably come from Mexico. By late March, she had been alive for a long time! She had survived last fall's migration to Mexico, the 5-month winter, and also a 1,000-mile spring migration as far as Arkansas.

She is spending the last days of her life in the safety of Dr. Jim Edson's lab laying eggs for the next generation. Here's her egg count to date:

Egg Count
Cumulative Total (by date)
As of this Date
# Eggs Laid
Dr. Edson's Comments
# Eggs Laid Today

31 Mar

(Nobody knows)

Captured in Monticello, Arkansas. Nobody knows how many eggs she had laid before she reached Arkansas.  

1 Apr


No new eggs yet...  

2 Apr


No new eggs yet...  

3 Apr


Well, Ms. Monarch decided to start laying eggs Sunday, April 3rd. On that day she laid 93. (The other female monarch I caught passed away over the weekend.)


4 Apr


Today, April 4th, she has laid more for a two-day total of 147! Attached is a picture of her in her nursery and a couple of shots of her eggs. Some of her sisters have been coming through because my plants outside now have close to 100 eggs on them. They are a little harder to count, so I'm not sure of the exact total. Now all I need are enough milkweed plants to feed them!!



5 Apr


Well Ms. Monarch is certainly loaded with eggs. Today she laid (to be correct, I guess I should say oviposited) so many eggs she's reached 250.  
6 Apr
Egg count today makes the grand total 322. In just 4 days she has passed the total for the spring 2002 monarch. If all of these eggs hatch, I'm going to have trouble finding enough milkweed to keep them well fed.  

7 Apr


At 7:30 I put a fresh milkweed plant in with momma monarch. At 12:30 CDT she had laid 23 eggs in that 5 hours. At 4:12 pm CDT the final egg count for the day brings her total to 374!!  

8 Apr


In addition to all of the eggs I already have, Ms. Monarch laid so many more today that our total rose to 436. the eggs that were laid on April 4th have started to hatch. Now I'm going to have a lot of hungry mouths to feed. Dennis Thurman and his biology students at Drew Central High School have been working in their greenhouse raising some milkweed for me. I just hope there is going to be enough to go around.  

9 Apr


New eggs laid today bring the total to 497...  
10 Apr 504 New eggs laid today bring the total to 504...  
11 Apr 504 No new eggs laid today...  
12 Apr 504 Or today...  
13 Apr 504 I believe she is finished with her egg laying. I have caterpillars hatching out all over the place. Due to the limited amount of milkweed available, I have turned to using an artificial diet I was able to buy from Educational Science Company. I tried it last fall with pretty good results. I will probably move the larvae back over to milkweed as more becomes available. I have been checking on the native milkweed in the area, but it is just barely big enough to pick. If we have some warm weather the rest of the week it should be ready to harvest. The tropical milkweed in the greenhouse is almost ready as well, so by Monday (April 18th) I should be in good shape.
14 Apr   No more news to report. Tomorrow one of my students will begin moving some of the caterpillars into contains with the artificial diet. There are probably close to two hundred at the 2nd instar stage  

Try This!

  • How many eggs did Ms. Monarch oviposit each day? Fill in chart above.
  • How many eggs do you think she will lay in total?
  • How much longer do you think she will live?
  • So far, what is the average number of eggs she has laid per day?
  • Graph your results, and describe what you see. (Then see our example.)
  • Predict how you think her egg-laying behavior will change over time.

National Science Education Standards

  • Use data to conduct a reasonable explanation.
  • Plants and animals have life cycles that include being born, developing into adults, reproducing, and eventually dying.
  • Reproduction is a characteristic of all living systems; because no individual organism lives forever, reproduction is essential to the continuation of every species.

National Math Standards

  • Compute fluently and make reasonable estimates.
  • Solve problems that arise in mathematics and in other contexts.
  • Develop and evaluate inferences and predictions that are based on data.