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

South Korea Divided on Response to North’s Cyber Attack

In past five years, officials in Seoul have accused Pyongyang of hacking into banks, government websites, causing chaos and inflicting millions of dollars in damages More

Video Calm Amid Fear in Daily Life in S. Sudan’s Bentiu

Residents have been trying to regain some sense of normalcy, but planning for the future remains uncertain as fear of attacks looms More

2015 Could Be Watershed for Syria Conflict

Republican control of US Senate in January could lead to more aggressive policy against IS militants in Syria - and against regime of Bashar al-Assad More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Jane Monheit Christmas Speciali
X
December 22, 2014 8:15 PM
Chanteuse Jane Monheit sings the holiday classic “Have Yourself a Merry Little Christmas,” and explains why it’s her favorite song of the season.
Video

Video Jane Monheit Christmas Special

Chanteuse Jane Monheit sings the holiday classic “Have Yourself a Merry Little Christmas,” and explains why it’s her favorite song of the season.
Video

Video Trade Talks Could Heat Up in 2015

With boosting trade a top priority for the Obama administration, 2015 may be the year that an agreement is finally reached on the Trans Pacific Partnership. But the trade deal, which is intended to boost trade between 12 Pacific countries, faces opposition as VOA's Jim Randle reports.
Video

Video Ugandan Doctors Aid Victims of Sudan's Civil War

In Sudan's state of South Kordofan, the number of amputees as result of civil war is in the thousands, but few have access to sufficient medical help. Adam Bailes recently visited the area and says a small team of Ugandan doctors has been providing remote help, producing new prosthetic limbs for those in need.
Video

Video Calm Amid Fear in Daily Life in S. Sudan’s Town of Bentiu

Six months ago, Bentiu was a ghost town. The capital of northern Unity State, near South Sudan’s important oil fields, had changed hands several times in fighting between government forces and rebels. Calm returned in November and since then, residents of Bentiu have been trying to regain some sense of normalcy. Bentiu’s market has reopened there are plans to start school again. But fears of new attacks hang heavy, as Benno Muchler reports from Bentiu.
Video

Video US Business Groups Press for Greater Access to Cuba

President Barack Obama's decision to do all he can to ease restrictions on U.S. trade, travel and financial activities with Cuba has drawn criticism from some conservatives and Republicans. People who bring tourists to the island and farmers who want to sell more food to Cuba, however, think they can do a lot more business with Cuba. VOA's Jim Randle reports.
Video

Video Three Cities Bid for Future Obama Presidential Library

President Barack Obama still has two years left in his term in office, but the effort to establish his post-presidential library is already underway. The bid for the Obama Presidential Library is down to four locations in three states -- New York, Hawaii, and Illinois. As VOA’s Kane Farabaugh reports, each of them played an important part in the president’s life before he reached the White House.
Video

Video Fears of More Political Gridlock in 2015

2014 proved to be a difficult year politically for President Barack Obama and a very good year for the U.S. Republican Party. Republican gains in the November midterm elections gave them control of the Senate and House of Representatives for the next two years -- setting the stage for more confrontation and gridlock in the final two years of the Obama presidency. VOA National Correspondent Jim Malone has a preview from Washington.
Video

Video Sudan School Becomes Target of Aerial Attacks

The school dropout rate is at an all-time high in Sudan's South Kordofan state because many schools have been destroyed during the three-year civil war between the government and SPLA-N rebel forces. Adam Bailes visited Sudan's Nuba Mountains' region and reports many children are simply too scared to go to school

All About America

AppleAndroid