Good news and bad news for monarch butterflies

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If you’re a fan of monarch butterflies, I’ve got good news and bad news. First the good news.

Last year the folks at Project Monarch Watch sent three monarch caterpillars into space via the shuttle Atlantis. On November 16, 2009, they were delivered to the International Space Station where they lived out their lives.

These monarchs are now back at Monarch Watch headquarters in Kansas and will become part of a permanent display at Monarch Watch.

Journey

The entire venture was a most curious trip. Three monarch larvae were sent from Kansas to Florida, delivered to the shuttle Atlantis as part of the payload for a mission that took them to the International Space Station.

Aboard the International Space Station they fed on an artificial diet created by Monarch Watch, molting from 4th into 5th instars and into chrysalises, and finally becoming adults.

The shuttle Endeavour returned the monarchs to Earth on Feb. 21.

From there the monarch habitat was shipped to BioServe Space Technologies at the University of Colorado in Boulder — the specialists who coordinate biologically-based science experiments for NASA.

Back home

BioServe sent the monarchs back to Monarch Watch on March 4, thus completing a most amazing 40.2 million mile journey.

The entire venture, including interactions with numerous schools, teacher evaluations of the project, photos, videos and a summary of what was learned from this project can be found at http://Monarch Watch .org/space.

The bad butterfly news is that a severe winter storm wreaked havoc on both the people and millions of monarchs that overwinter in the mountains of the Mexican state of Michoacan.

During the first four days of February, unprecedented rainfall devastated the area. Flooding and landslides left nearly 50 people dead and small towns in the area were nearly destroyed.

The toll on the butterflies has been difficult to determine. One report from Monarch Watch concluded that more than half of the overwintering butterflies died. That could be as many as 10 million monarchs removed from the population that is now heading north.

The mountain reserves where the monarchs gather from December through February are dominated by oyamel fir trees.

Normally the microhabitat provided by the trees’ needles provides protection from winter weather, which is normally mild. But when snow, sleet and heavy rains pummel the area, the butterflies take a beating.

Possible outcome

Monarch Watch fears that the number of monarchs returning to the U.S. and Canada this year will be fewer than at any time since these wintering colonies were discovered in 1975. And that will likely mean far fewer monarchs returning to Mexico in September.

What makes the monarch migration so amazing is that each butterfly makes the trip only once. The monarchs that fly to Mexico are from the last brood of the summer, usually hatched in August.

On the winter grounds monarchs are sluggish and inactive, and they congregate on tree trunks by the millions. During the winter, monarchs burn little of their fat reserves. By early March, they still have plenty of stored energy for the return trip north.

Mating occurs before migration begins, and females lay eggs on milkweed plants as they move north through Texas. After reaching the southern states, these individuals, which have lived as long as eight months, die. But the eggs they leave behind ensure a new generation.

This new generation continues northward, laying eggs as it goes, until several generations later adult monarchs reach the northern limits of milkweed distribution.

Individuals from these summer broods live only three to five weeks, just long enough to reproduce. The final summer brood is the one that returns to the mountains of Mexico.

Due to their complex life history, several generations of monarchs separate those that leave the winter roost from those that head south in the fall. Yet somehow, inexperienced monarchs return to their ancestors’ traditional wintering areas.

Help needed

Severe winter weather like that experienced in February disrupts monarch biology. Citizen scientists everywhere are needed to monitor monarch numbers this summer.

Journey North provides an opportunity for anyone to report monarch sightings and monitor their northward progress on maps at http://www.learner.org/jnorth/monarch/index.html.

(Send questions and comments to Dr. Scott Shalaway, RD 5, Cameron, WV 26033 or via e-mail at his Web site, http://scottshalaway.googlepages.com.)

About the Author

Scott Shalaway, who holds a Ph.D. in wildlife ecology from Michigan State University, writes from his home in rural West Virginia. A former faculty member at Oklahoma State University and the University of Oklahoma Biological Station, he has been writing a weekly nature column for newspapers and freelancing for magazines since 1986. Send questions and comments to scottshalaway@gmail.com. You can also visit his Web site, http://scottshalaway.googlepages.com. More Stories by Scott Shalaway

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