Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Insect Outbreaks
Name: Bonnie
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: N/A


Question:
Hi, I made a trip to Washington DC in the 80's as we passed through Virgina, they were being invaded by large locast that looked like huge grasshoppers. So many on the highway it was slippery on exit ramps, so loud you could not hear the radio & it drowned out hte sound of the large trailer trucks passing by. What was the reason for this & does it happen often? No one I talk to belives me.


Replies:
When you mention that they were loud, I believe that you were seeing cicadas, not true locusts (which ARE grasshoppers).

Some species of these tremendously loud insects have a very long life cycle: enormous cohorts arrive every 17 years. There are so many that predators cannot eat them all and cannot make a dent in their population. So huge numbers of cicadas mate and lay eggs in a single summer, and the huge number of larvae grow and grow over the next 17 years, and then the adults erupt onto the scene once again, making the spectacle you describe. I remember it well from my childhood in Maryland.

Richard E. Barrans Jr., Ph.D., M.Ed.
Department of Physics and Astronomy
University of Wyoming


Grasshopper outbreaks tend to be cyclical and dependant on climate and other insect populations. Often drought conditions will encourage grasshopper outbreaks. Sunlight and high heat and humidity discourage important grasshopper pathogens and are increase the speed of egg/nymph/adult development. Depending on what year it was, 1988 had a massive drought over the U.S. These conditions could have made it favorable for a grasshopper outbreak!

Grace Fields


Click here to return to the Zoology Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory