Migrating Moths Can Fly High, Far, and Fast
By Hank Becker
March 10, 1997
Alien moth pests can spread surprisingly far and fast--even over the ocean.
Scientists with USDAs
Agricultural Research Service have
identified the travel rates of 10 foreign species of moths--from the scientific
family Lepidoptera--introduced into North America. Moths are some of the
most destructive pests of U.S. crops.
Aggressive species of crop-destroying moths can spread up to 113 miles a
year, although most travel 15 to 28 miles a year. The European gypsy moth
spreads the slowest, about 8 miles a year, probably because of its flightless
females. The browntail moth and satin moth are members of the same family as
the gypsy moth, but their flying females spread much faster at 26 and 28 miles
per year, respectively.
The fastest-spreading species are two cutworm moths. One travels 113 miles a
year and the other can fly at least 99 miles in one continuous flight (over
water). It can take from 30 to 100 years for an introduced species to occupy
all suitable habitat in the United States and Canada. Nearly all accidentally
introduced Lepidoptera--about 123 species--are of European origin. Six
of the 10 studied came into the U.S. from both the East and West coasts.
Seaports, rather than airports, have been the major points of entry.
This new information on moth travel will be useful to scientists working on
insect pest control strategies, especially integrated pest management efforts
where growers cooperate across county and state lines.
The February issue of ARS Agricultural Research magazine
contains an article on moth-migration research. The magazine can also be found
on the World Wide Web in .pdf (Portable Document Format) files at:
Scientific contact: Douglas C. Ferguson,
USDA-ARS Systematic Entomology
Laboratory, Washington, D.C., phone (202) 382-1785, e-mail