Unwelcome Immigrants: Can the U.S. Thwart Asian Moths?

The Asian cousins of North America's tree-munching gypsy moths are crossing the Pacific on cargo ships and could establish a beachhead in the U.S.
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The gypsy moth caterpillar defoliates forests and kills trees around the world. This photo shows two varieties of adult gypsy moths. Females of the Asian variety [ top row, with female on the left ] can fly, whereas North American females can't.....[ More ]


An Asian gypsy moth caterpillar, or larva, the stage at which the species is responsible for eating the leaves off trees. The caterpillars come in a variety of sizes and colors.....[ More ]


A majority of the adult females from a European hybrid strain in Poland have the longer wings required to fly.....[ More ]


The Portuguese hybrid female has shorter wings and can't fly. The nonflyers tend to stay close to the place where they emerged from their pupal stage.....[ More ]


A U.S. Forest Service researcher, using a caliper, measures the wing spread of an adult female gypsy moth. Of the Asian variety, she has the wing size and muscles required to fly.....[ More ]


U.S. Forest Service researchers bred nonflying North American with flying Russian gypsy moths and discovered that some of their offspring could fly. Shown here, two hybrid females achieve flight in a Forest Service lab in Ansonia, Conn.....[ More ]


Gypsy moths need wing muscles to aid them in flight. In this photo, a Forest Service researcher holds a hybrid female on her back. If she has the muscle strength to fly, she'll be able to flip herself over with just one or two flaps of her wings.....[ More ]


The same female hybrid as in the previous photo flutters her wings in an attempt to right herself, an indication that she may have the muscle strength to fly.....[ More ]


Melody Keena, a U.S. Forest Service entomologist, studies gypsy moth egg masses. These eggs are stored on rolls of paper in the Forest Service's quarantine lab in Ansonia, Conn.....[ More ]


This photo shows Keena opening a plastic container of gypsy moth eggs stored in the Ansonia quarantine lab.....[ More ]


These are pinned specimens showing the generations involved in the breeding experiments that crossed Asian and North American gypsy moths. The light-colored moths at the top are females and the dark ones below are male.....[ More ]


Russian females of the Asian strain are shown resting here on a building in a far eastern Russian port city during a 2005 outbreak.....[ More ]


A New Zealand scientist, John Handiside, on the left, training colleagues from the Russian forest service to monitor gypsy moth traps in the forests around Nadhodka, a shipping port in far eastern Russia.....[ More ]

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