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.

You May Like

Nigeria Incumbent in Tight Spot as Poll Nears

Muhammadu Buhari is running a strong challenge to Goodluck Jonathan, amid a faltering economy and Boko Haram security worries More

Video Liberia's Almost Last Ebola Patient Grateful but Still Grieving

Beatrice Yardolo tells VOA that despite her fame, life is still a struggle as she waits for government's promise of support to arrive More

Video Cambodian Land Grabs Threaten Traditional Communities

At least seven different indigenous groups in Ratanakiri depend mainly on forest products for their survival, say they face loss of their land, traditional way of life More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Liberia's Almost Last Ebola Patient Grateful but Still Grievingi
X
Benno Muchler
March 26, 2015 3:41 PM
Beatrice Yardolo was to make history as Liberia’s last Ebola patient. Liberians recently started counting down 42 days, the period that has to go by without a single new infection until the World Health Organization can declare a country Ebola-free. That countdown stopped on March 20 when there was another new case of Ebola, making Yardolo’s story a reminder that Ebola is far from over. Benno Muchler reports from Monrovia.
Video

Video Liberia's Almost Last Ebola Patient Grateful but Still Grieving

Beatrice Yardolo was to make history as Liberia’s last Ebola patient. Liberians recently started counting down 42 days, the period that has to go by without a single new infection until the World Health Organization can declare a country Ebola-free. That countdown stopped on March 20 when there was another new case of Ebola, making Yardolo’s story a reminder that Ebola is far from over. Benno Muchler reports from Monrovia.
Video

Video Cambodian Land Grabs Threaten Traditional Communities

Indigenous communities in Cambodia's Ratanakiri province say the government’s economic land concession policy is taking away their land and traditional way of life, making many fear that their identity will soon be lost. Local authorities, though, have denied this is the case. VOA's Say Mony went to investigate and filed this report, narrated by Colin Lovett.
Video

Video US, South Korea Conduct Joint Military Exercises

The Eighth U.S. Army Division and the Eighth Republic of Korea Mechanized Infantry Division put on a well orchestrated show of force for the media this week during their joint military training exercises in South Korea. VOA’s Seoul correspondent Brian Padden was there and reports the soldiers were well disciplined both in conducting a complex live fire exercise and in staying on message with the press.
Video

Video Space Program Status Disappoints 'Last Man on the Moon'

One of the films that drew big crowds last week at the annual South by Southwest festival in Austin, Texas, tells the story of the last human being to stand on the moon, U.S. astronaut Eugene Cernan. It has been 42 years since Cernan returned from the moon and he laments that no one else has gone there since. VOA’s Greg Flakus reports.
Video

Video Young Filmmakers Shine Spotlight on Giving Back

A group of student filmmakers from across the United States joined President Barack Obama at the White House this month for the second annual White House Student Film Festival. Fifteen short films were officially selected from more than 1,500 entries by students aged 6 through 18. The filmmakers and their families then joined the president and a group of celebrities for a screening of their films. VOA’s Julie Taboh reports.
Video

Video VOA Exclusive: Interview with Afghan President Ashraf Ghani

Afghan President Ashraf Ghani, during his first visit as president to Washington, gave a one-on-one interview with VOA Afghan Service reporter Said Suleiman Ashna, about his request for a change in U.S. troop levels, the threat from the Islamic State, and repairing relations with the United States and Pakistan. The interview was held at Blair House, late Sunday, in Pashto.
Video

Video California Science Center Tells Story of Dead Sea Scrolls

The ancient manuscripts were uncovered in the mid-20th century, and they are still yielding clues about life and religious beliefs in ancient Israel. As VOA's Mike O'Sullivan reports, an exhibit in Los Angeles shows how modern science is bringing the history of these ancient documents to life.
Video

Video Angelina Jolie Takes Another Bold Step

Hollywood actress and filmmaker Angelina Jolie has revealed she had her ovaries and fallopian tubes removed to lower her odds of getting cancer. Doctors say the huge publicity over her decision will help raise awareness about the importance of cancer screening. VOA’s George Putic has more

All About America

Circumventing Censorship

An Internet Primer for Healthy Web Habits

As surveillance and censoring technologies advance, so, too, do new tools for your computer or mobile device that help protect your privacy and break through Internet censorship.
More