News / Science & Technology

    Wasp Recruited to Fight Invasive Beetle

    Wasps Recruited to Battle Invasive Beetlei
    X
    July 17, 2014 2:15 AM
    Scientists in Maryland are pitting insects against insects in a battle to control an invasive species. Around the world, non-indigenous plants and animals cost an estimated $1.4 trillion in damage and control expenses, according to the United Nations. But rather than spraying pesticides that risk doing additional harm, researchers are bringing in the invasive species' natural predators to try to restore balance. VOA's Steve Baragona has the story.

    Scientists are pitting insects against insects in a battle to control an invasive species.

    U.S. Department of Agriculture researchers have released tiny parasitic wasps in forests in Maryland to attack the emerald ash borer, an invader from China that is devastating forests across the northern United States.

    By the end of this decade, this insect will have done an estimated $10 billion of damage nationwide, according to one study.

    Plant and animal hitchhikers traversing the planet in our globalized economy have made invasive species a $1.4 trillion-a-year problem worldwide, says the United Nations.

    But rather than spraying pesticides that risk doing additional harm, the USDA scientists are bringing the invasive insect’s natural predators in from Asia to try to restore balance.

    Forests at risk

    Beneath the bark of an infested ash tree, the borer’s larvae carve twisting paths that cut off the supply of nutrients. It’s like slashing the tree’s arteries.

    "There is a possibility some species may be completely wiped out by this beetle,” said USDA entomologist Jian Duan. “And you can imagine the cascading effect of losing a tree species in our native forest."

    Ash trees make up 20 to 40 percent of some northern U.S. forests. The emerald ash borer threatens them and all the creatures that depend on them.

    When the borer arrived from China in the 1990s - likely in a wooden crate or shipping pallet - it had no natural enemies here.

    Consorting with the enemy

    In Asia, several species of parasitic wasps lay their own eggs inside borers’ eggs. The young wasps steal the developing borer's food, and the borer dies. Other wasps lay eggs in the larva itself. The eggs hatch and eat the larva alive as they grow.

    It’s a grizzly but effective way to keep the emerald ash borer’s population in check.

    So Duan is introducing these wasps to forests under attack.

    Wasps are used successfully to control cassava mealybugs in Africa and many other invasive pests.

    Quarantine

    But Duan knows that fighting an invasive insect with another import can be risky. It could become invasive, too.

    So his lab raises wasps in quarantine while they're tested. He will only release picky eaters: wasps that would much rather attack an emerald ash borer than a native insect.

    So far, Duan’s team has released three species of wasps. There are early signs that they are helping to slow the emerald ash borer’s advance. But they have a big job ahead of them.

    While they have released several thousand wasps, one infested tree can produce hundreds of emerald ash borers. “It's really a drop in the ocean," Duan said.

    "You have to think long-term,” he added.

    Now Duan and his team will watch and wait to see if the wasps can return some balance to an ecosystem at risk.


    Steve Baragona

    Steve Baragona is an award-winning multimedia journalist covering science, environment and health.

    He spent eight years in molecular biology and infectious disease research before deciding that writing about science was more fun than doing it. He graduated from the University of North Carolina at Chapel Hill with a master’s degree in journalism in 2002.

    You May Like

    Post-White House, Obamas to Rent Washington Mansion

    Nine-bedroom home is 3 kilometers from Oval Office, near capital's Embassy Row; rent estimated at around $22,000 a month

    Red Planet? Not so much!

    New research suggest that Mars is in a warm period between cyclical ice ages, and that during Ice Age Maximum over 500,000 years ago, the red planet was decidedly ice, and much whiter to the naked eye.

    Taj Mahal Battles New Threat from Insects

    Swarms of insects are proliferating in the heavily contaminated waters of the Yamuna River, which flows behind the 17th century monument

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    Vietnamese-American Youth Optimistic About Obama's Visit to Vietnami
    X
    Elizabeth Lee
    May 22, 2016 6:04 AM
    U.S. President Barack Obama's visit to Vietnam later this month comes at a time when Vietnam is seeking stronger ties with the United States. Many Vietnamese Americans, especially the younger generation, are optimistic Obama’s trip will help further reconciliation between the two former foes. Elizabeth Lee has more from the community called "Little Saigon" located south of Los Angeles.
    Video

    Video Vietnamese-American Youth Optimistic About Obama's Visit to Vietnam

    U.S. President Barack Obama's visit to Vietnam later this month comes at a time when Vietnam is seeking stronger ties with the United States. Many Vietnamese Americans, especially the younger generation, are optimistic Obama’s trip will help further reconciliation between the two former foes. Elizabeth Lee has more from the community called "Little Saigon" located south of Los Angeles.
    Video

    Video First-generation, Afghan-American Student Sets Sights on Basketball Glory

    Their parents are immigrants to the United States. They are kids who live between two worlds -- their parents' homeland and the U.S. For many of them, they feel most "American" at school. It can be tricky balancing both worlds. In this report, produced by Beth Mendelson, Arash Arabasadi tells us about one Afghan-American student who seems to be coping -- one shot at a time.
    Video

    Video Newest US Citizens, Writing the Next Great Chapter

    While universities across the United States honor their newest graduates this Friday, many immigrants in downtown Manhattan are celebrating, too. One hundred of them, representing 31 countries across four continents, graduated as U.S. citizens, joining the ranks of 680,000 others every year in New York and cities around the country.
    Video

    Video Vietnam Sees Strong Economic Growth Despite Incomplete Reforms

    Vietnam has transformed its communist economy to become one of the world's fastest-growing nations. While the reforms are incomplete, multinational corporations see a profitable future in Vietnam and have made major investments -- as VOA's Jim Randle reports.
    Video

    Video Qatar Denies World Cup Corruption

    The head of Qatar’s organizing committee for the 2022 World Cup insists his country's bid to host the soccer tournament was completely clean, despite the corruption scandals that have rocked the sport’s governing body, FIFA. Hassan Al-Thawadi also said new laws would offer protection to migrants working on World Cup construction projects. VOA's Henry Ridgwell reports.
    Video

    Video Infrastructure Funding Puts Cambodia on Front Line of International Politics

    When leaders of the world’s seven most developed economies meet in Japan next week, demands for infrastructure investment world wide will be high on the agenda. Japanese Prime Minister Shinzo Abe’s push for “quality infrastructure investment” throughout Asia has been widely viewed as a counter to the rise of Chinese investment flooding into region.
    Video

    Video Democrats Fear Party Unity a Casualty in Clinton-Sanders Battle

    Democratic presidential front-runner Hillary Clinton claimed a narrow victory in Tuesday's Kentucky primary even as rival Bernie Sanders won in Oregon. Tensions between the two campaigns are rising, prompting fears that the party will have a difficult time unifying to face the presumptive Republican nominee, Donald Trump. VOA national correspondent Jim Malone has more from Washington.
    Video

    Video Portrait of a Transgender Marriage: Husband and Wife Navigate New Roles

    As controversy continues in North Carolina over the use of public bathrooms by transgender individuals, personal struggles with gender identity that were once secret are now coming to light. VOA’s Tina Trinh explored the ramifications for one couple as part of trans.formation, a series of stories on transgender issues.
    Video

    Video Amerikan Hero Flips Stereotype of Middle Eastern Character

    An Iranian American comedian is hoping to connect with American audiences through a film that inverts some of Hollywood's stereotypes about Middle Eastern characters. Sama Dizayee reports.
    Video

    Video Budding Young Inventors Tackle City's Problems with 3-D Printing

    Every city has problems, and local officials and politicians are often frustrated by their inability to solve them. But surprising solutions can come from unexpected places. Students in Baltimore. Maryland, took up the challenge to solve problems they identified in their city, and came up with projects and products to make a difference. VOA's June Soh has more on a digital fabrication competition primarily focused on 3-D design and printing. Carol Pearson narrates.

    Special Report

    Adrift The Invisible African Diaspora