The Mediterranean fruit fly (Ceratitis capitata),
commonly called the medfly, is one of the world's most destructive agricultural
Also with the potential to cause a large amount of damage
to agricultural crops are the melon fly, oriental fruit fly, and Malaysian
fruit fly, all foreign to the United States. These four species can
turn more than 400 different fruits and vegetables into maggot-infested
inedible mush, including citrus, eggplant, guava, loquat, mango, melon,
papaya, passion fruit, peach, pepper, persimmon, plum, star fruit, tomato,
The only place these four fruit flies have become established
in the United States are the islands of Hawaii, where the flies have
devastated local farms, large and small, and necessitated heavy use
of chemical pesticides on many crops.
Many fruit fly control techniques being used around the
world have their genesis in research that the Agricultural
Research Service (ARS) has carried out in the Pacific since the
1950s. Hawaii has been infested by exotic fruit flies since the late
1800s, and it has been an ideal test location for development of control
methods because there is no chance of further spread.
Techniques such as more effective species-specific lures
and baits, improved ways of producing sterile male fruit flies released
to short-circuit the breeding cycle, new biocontrols such as augmentative
releases of parasitic wasps, and more effective crop management techniques
have all come from ARS's U.S. Pacific Basin Agricultural Research Center
in Hilo, Hawaii. But until recently the techniques developed there had
not been put to work in a systematic package to deal with Hawaii's own
fruit fly problem.
Now, use of these techniques has come home to Hawaii in
an ARS-led program called the Hawaii Area Wide Fruit Fly Integrated
Pest Management (HAW-FLYPM) program. ARS teamed up with the Hawaii Department
of Agriculture and the University of Hawaii to put together a program
of techniques to control medfly, melon fly, Malaysian fruit fly, and
oriental fruit fly and to help Hawaiian farmers implement it.
Just 4 years under way, the HAW-FLYPM program is already
having tremendous success. Hawaiian farmers who have adopted the integrated
pest management plan are finding they can cut chemical pesticide use
by 75 to 95 percent and grow crops they had once given up on because
of fruit fly damage.
Hawaiian growers couldn't be more pleased, but they aren't
the only ones who may benefit from this success. Many people are keeping
an eye on the work. California, Florida, and Texas, in particular, have
a keen interest in the program's ability to control fruit flies.
California is especially attentive. Keeping medfly out
of California has cost nearly $500 million during the past 25 years.
And that figure is a drop in the bucket compared to the more than $1.4
billion annual loss estimated for California if medfly were to become
established there. These losses would come from lost markets, export
sanctions, treatment costs, and reduced crop yields.
By keeping abreast of the Hawaii fruit fly program, California
could gain valuable information about how to make control measures more
effective to deal with their periodic outbreaks. The state could also
gain access to new technology, such as better baits and traps.
Just as important to California is whether or not Hawaii
will seek to export more fruits and vegetables as its fruit fly infestation
comes under control. Hawaii is the only state under quarantine for fruit
and vegetable export because of exotic fruit flies. California will
want to ensure new Hawaiian exports don't pose additional danger.
Just as other states are interested in how well the HAW-FLYPM
program is doing, so are other countries. Researchers and officials
from Australia, the Commonwealth of the Northern Mariana Islands, Fiji,
French Polynesia, Guam, South Africa, Taiwan, and Vanuatu are checking
out the ARS-led program. They are watching the HAW-FLYPM program as
a model for fruit fly suppression.
Countries, especially along the Pacific Rim, are adopting
areawide pest management to suppress fruit flies by closely interacting
with program scientists in Hawaii.
Fruit flies often spread through imports of produce. With
increasingly global trade, all countries are seeking the most effective
tools to deal with these pestswhether it is controlling them at
home or keeping them out in the first place.
Eradicating fruit flies, especially invasive species,
in one country won't completely solve its problem if it is just going
to get fruit flies right back from another source.
Of course, it is also to Hawaii's and the rest of the
United States' benefit if other countries control fruit flies at home.
A decreased chance of fruit fly invasion can only provide better protection
for U.S. agriculture. This makes the exchange of expertise and research
essential to a fruit fly-free future.
ARS Hawaii Area Wide Fruit Fly Control Program
U.S. Pacific Basin Agricultural Research Center
Robert M. Faust
ARS Senior National Program Leader
Field and Horticultural Crop Entomology
"Forum" was published in the February
2004 issue of Agricultural Research magazine.