News / Asia

Overgrazing Linked to Locust Outbreaks

Nutrient-poor land in Inner Mongolia proves fertile for swarms

A locust in its grassland habitat - a heavily-grazed field in Inner Mongolia.
A locust in its grassland habitat - a heavily-grazed field in Inner Mongolia.

Multimedia

Audio

Livestock overgrazing can lead to outbreaks of ravenous locusts, according to a new study.

Overgrazing is already known to lead to erosion and reduce the fertility of pasture lands.



But the researchers were surprised to find overgrazed, nutrient-poor land in Inner Mongolia was actually fertile ground for a species of locust native to the region.

"It's a counter-intuitive result," says Arianne Cease at Arizona State University, lead author of the study published in Science.

Arianne Cease, left, and field assistants collect grass in a heavily-razed field to test for plant nitrogen, carbon and protein content.
Arianne Cease, left, and field assistants collect grass in a heavily-razed field to test for plant nitrogen, carbon and protein content.

Cease and her team thought the locusts they studied might not form swarms if they had access to well-fertilized vegitation which was high in protein.

Locust killer

“What we found was that the high-protein diet was actually very deleterious to this locust. It caused most of them to die." On the other hand, she says, they found this particular locust thrived on low-protein grasses found on eroded, overgrazed land. "They actually need what's typically thought of as a poor-quality food to build up to high population levels."  

University of Sydney biologist Stephen Simpson notes that, as the Eurasian grasslands have been degraded by  livestock grazing and erosion, locust outbreaks have increased.

"The authors have shown that they are indeed linked," he says. "Understanding this relationship will help in the development of land management practices that reduce the locust threat."

Fertilizing an over-grazed field to raise plants’ protein levels might actually help control this insect, according to Cease's research.

Different impacts

However, the same may not be true for all locusts, cautions Keith Cressman, chief of locust outbreak forecasting at the U.N. Food and Agriculture Organization.

Researchers have found just the opposite effect in desert locusts, which Cressman says are perhaps the most destructive. “When the insects eat leaves high in [protein], they will reproduce more, they will grow faster, they will increase in number, they will survive better and they’re just a healthier locust.”

Cressman says the relationships between livestock, land and locusts are complex and differ from place to place. More research will be needed to sort them out completely.

Cease plans studies in Africa on how grazing practices affect other species of locusts.

You May Like

Video British Fighters on Frontline of Islamic State Information War

It’s estimated that several hundred British citizens are fighting for Islamic State alongside other foreign jihadists More

Pakistan's Political Turmoil Again Shines Spotlight on Military

Thousands of protesters calling for PM Sharif to step down continue protests in front of parliament, as critics fear political impasse could spur another military coup More

Photogallery Ebola Quarantines Spark Anxiety in Liberian Capital

Food prices rise sharply as residents attempting purchases clash with security forces, leaving one person dead More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Native Bees May Help Save Cropsi
X
Deborah Block
August 22, 2014 12:23 AM
U.S. President Barack Obama has called for a federal strategy to promote the health of bees that have been declining. The honeybee has been waning due to parasites, disease and pesticides. Wild bees may be used to take over their role as crop pollinators. Scientists first need to learn a lot more about wild bees, says biologist Sam Droege, who is pioneering the first national inventory on native bees. VOA’s Deborah Block went to his research laboratory in Beltsville, Maryland, to bring you more.
Video

Video Native Bees May Help Save Crops

U.S. President Barack Obama has called for a federal strategy to promote the health of bees that have been declining. The honeybee has been waning due to parasites, disease and pesticides. Wild bees may be used to take over their role as crop pollinators. Scientists first need to learn a lot more about wild bees, says biologist Sam Droege, who is pioneering the first national inventory on native bees. VOA’s Deborah Block went to his research laboratory in Beltsville, Maryland, to bring you more.
Video

Video US Defense Officials Plan for Long-Term Strategy to Contain Islamic State

U.S. defense officials say American air strikes in Iraq have helped deter Islamic State militants for the time being, but that a broad international effort is needed to defeat the extremists permanently. Defense Secretary Chuck Hagel warned Thursday that the group formerly known as the Islamic State in Iraq and the Levant, or ISIL, is better organized, and financially and militarily stronger than any other known terrorist group. Zlatica Hoke has more.
Video

Video Drug-Resistant Malaria Spreads in Southeast Asia

On Thailand’s border with Myanmar, also known as Burma, a malaria research and treatment clinic is stepping up efforts to eliminate a drug-resistant form of the parasite - before it spreads abroad. Steve Sandford reports from Mae Sot, Thailand.
Video

Video Gaza Conflict, Hamas Popularity Challenge Abbas

The Palestinian unity government of Mahmoud Abbas has failed to convince Hamas to agree to Egyptian-negotiated terms with Israel on a Gaza cease-fire. VOA State Department Correspondent Scott Stearns reports on what the Gaza conflict means for President Abbas, with whom U.S. officials have worked for years on a two-state solution to the Israeli-Palestinian conflict.
Video

Video Nigeria's 'Nollywood' Movie Industry Rolls in High Gear

Twenty years after its birth in a video shop in Lagos, Nigeria's "Nollywood" is one of the most prolific film industries on earth. Despite low budgets and whirlwind production schedules, Nigerian films are wildly popular in Africa and industry professionals say they hope, in the future, their films will be as great in quality as they are in quantity. Heather Murdock has more for VOA from Lagos.
Video

Video UN Launches 'Biggest Aid Operation in 30 Years' in Iraq

The United Nations has launched what it describes as one of the biggest aid operations in 30 years in northern Iraq, as hundreds of thousands of refugees flee the extremist Sunni militant group calling itself the Islamic State. As Kurdish and Iraqi forces battle the Sunni insurgents, the fighting has forced more people to flee their homes. Kurdish authorities say the international community must act now to avert a humanitarian catastrophe. Henry Ridgwell reports for VOA from London.
Video

Video Cambodian American Hip Hop Artist Sings of Personal Struggles

A growing underground movement of Cambodian American hip hop artists is rapping about the struggles of living in urban America. Most, if not all of them, are refugees or children of refugees who came to the United States from Cambodia to escape the Khmer Rouge genocide of the 1970s. Through their music, the artists hope to give voice to immigrants who have been struggling quietly for years. Elizabeth Lee reports from Long Beach, California.
Video

Video African Media Tries to Educate Public About Ebola

While the Ebola epidemic continues to claim lives in West Africa, information technology specialists, together with radio and TV reporters, are battling misinformation and prejudice about the disease - using social media to educate the public about the deadly virus. VOA’s George Putic has more.

AppleAndroid