News / Science & Technology

Liar! Liar! African Bird Uses Elaborate Ruse to Steal Food

FILE - A drongo sits on a pole in a paddy field on the outskirts of Gauhati, India.
FILE - A drongo sits on a pole in a paddy field on the outskirts of Gauhati, India.
Reuters
If you believe honesty is the best policy, you would have a hard time convincing the forked-tailed drongo. This tricky African bird is the pathological liar of the animal kingdom.
 
Scientists described on Thursday how this medium-sized bird brazenly deceives other animals by mimicking alarm calls made by numerous bird species - and even meerkats - to warn of an approaching predator in a ruse to frighten them off and steal food they leave behind.
 
The researchers tracked 64 forked-tailed drongos over a span of nearly 850 hours in the Kalahari Desert in South Africa close to the Botswana border to unravel this unique behavior.
 
"They're rather demonic little black birds with red eyes, a hooked beak and a forked tail," said evolutionary biologist Tom Flower of the University of Cape Town in South Africa.
 
"They're also highly aggressive and are renowned for attacking eagles and hawks, for which they apparently have no fear," added Flower, whose study appears in the journal Science.
 
These birds, common in southern Africa, usually get meals the honest way, such as capturing insects in mid-air using their superb aerial skills.
 
But at other times, like on cold mornings when few insects are flitting around, the drongos turn to a life of crime.

False alarm
 
The drongos are able to mimic the sounds made by many different species that inhabit its desert environment, including birds such as pied babblers, glossy starlings, sociable weavers and pale chanting goshawks as well as mammals like meerkats.
 
The drongos carry out an elaborate con. They give their own genuine alarm call when they spot a predator approaching - essentially behaving as sentries - and other animals come to trust that this call signals real danger.
 
But they sometimes give this alarm call when no danger exists to fool other animals into fleeing and abandoning their food.
 
Then the drongos swoop down for a free lunch.
 
"All the animals in the Kalahari eavesdrop on each other's alarm calls, which provide invaluable information about potential predators. It's a bit of an information superhighway where all the animals speak each other's language," Flower said.
 
"Because drongos give reliable predator information some of the time, it maintains host responsiveness [of other animals] since they can never know if the drongo is lying or telling the truth," added Amanda Ridley, an evolutionary biologist at the University of Western Australia, another of the researchers.
 
The scientists noticed that sometimes the other animals "get wise" to the con and ignore repeated false alarm calls. But then the wily drongos simply grab another tool from their toolbox of trickery - they mimic the alarm calls made by other animals, once again conning them into fleeing and leaving their chow behind.
 
Flower observed drongos mimicking more than 50 calls.
 
When stealing food from other animals, drongos are able to eat larger prey than they normally would be able to capture on their own like scorpions, beetle larvae and even geckos.
 
"Crime pays," Flower said, noting that the stolen stuff accounted for about a quarter of the food eaten by the drongos.
 
"One could argue that the strategy of the drongo to steal food from others seems very dishonorable in human standards. But, yes, if it has found such a crafty way to catch food, which is usually much larger than the food items it catches itself, then we cannot help but admire this clever little bird's adaptiveness," Ridley added.
 
The researchers classify the drongo as "a kleptoparasite."
 
There are many examples of mimicry and deception in the animal kingdom. About 20 percent of song birds mimic the calls of other birds, Flower noted.
 
"However, drongos are the only ones to flexibly produce the specific signals that best deceive their different hosts and to maintain their deception racket by changing signal when the previous signal failed," Flower added

You May Like

FIFA Indictments Put Gold Cup Tournament Under Cloud

Experts say US indictments could lead to charges of other world soccer officials, and lead to major shakeup in sport's governance More

Seoul Sponsors Korean Unification Fair

Border communities promoted the benefits of increased cooperation and North Korean defectors shared their stories More

Video VOA EXCLUSIVE: Iraq President Vows to Fight IS 'Until They Are Killed or We Die'

In wide-ranging interview with VOA Persian service reporter, Fuad Masum describes conflict as new type of fight that will take time to win 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.
Expelled from Pakistan, Afghan Refugees Return to Increased Hardshipi
X
Ayesha Tanzeem
May 28, 2015 6:48 PM
Undocumented refugees returning to Afghanistan from Pakistan have no jobs, no support system, and no home return to, and international aid agencies say they and the government are overwhelmed and under-resourced. Ayesha Tanzeem has more from Kabul.
Video

Video Expelled from Pakistan, Afghan Refugees Return to Increased Hardship

Undocumented refugees returning to Afghanistan from Pakistan have no jobs, no support system, and no home return to, and international aid agencies say they and the government are overwhelmed and under-resourced. Ayesha Tanzeem has more from Kabul.
Video

Video Britain Makes Controversial Move to Crack Down on Extremism

Britain is moving to tighten controls on extremist rhetoric, even when it does not incite violence or hatred -- a move that some are concerned might unduly restrict basic freedoms. It is an issue many countries are grappling with as extremist groups gain power in the Middle East, fueled in part by donations and fighters from the West. VOA’s Al Pessin reports from London.
Video

Video Floodwaters Recede in Houston, but Rain Continues

Many parts of Texas are recovering from one of the worst natural disasters to hit the southwestern state. Heavy rains on Monday and early Tuesday caused rivers to swell in eastern and central Texas, washing away homes and killing at least 13 people. As VOA’s Greg Flakus reports from Houston, floodwaters are receding slowly in the country's fourth-largest city, and there likely is to be more rain in the coming days.
Video

Video 3D Printer Makes Replica of Iconic Sports Car

Cars with parts made by 3D printers are already on the road, but engineers are still learning about this new technology. While testing the possibility of printing an entire car, researchers at the U.S. Department of Energy recently created an electric-powered replica of an iconic sports roadster. VOA’s George Putic has more.
Video

Video Al-Shabab Recruitment Drive Still on In Kenya

The al-Shabab militants that have long battled for control of Somalia also have recruited thousands of young people in Kenya, leaving many families disconsolate. Mohammed Yusuf recently visited the Kenyan town of Isiolo, and met with relatives of those recruited, as well as a many who have helped with the recruiting.
Video

Video US Voters Seek Answers From Presidential Candidates on IS Gains

The growth of the Islamic State militant group in Iraq and Syria comes as the 2016 U.S. presidential campaign kicks off in the Midwest state of Iowa.   As VOA’s Kane Farabaugh reports, voters want to know how the candidates would handle recent militant gains in the Middle East.
Video

Video A Small Oasis on Kabul's Outskirts Provides Relief From Security Tensions

When people in Kabul want to get away from the city and relax, many choose Qargha Lake, a small resort on the outskirts of Kabul. Ayesha Tanzeem visited and talked with people about the precious oasis.
Video

Video Film Festival Looks at Indigenous Peoples, Culture Conflict

A recent Los Angeles film festival highlighted the plight of people caught between two cultures. Mike O'Sullivan has more on the the Garifuna International Film Festival, a Los Angeles forum created by a woman from Central America who wants the world to know more about her culture.
Video

Video Kenyans Lament Losing Sons to al-Shabab

There is agony, fear and lost hope in the Kenyan town of Isiolo, a key target of a new al-Shabab recruitment drive. VOA's Mohammed Yusuf visits Isiolo to speak with families and at least one man who says he was a recruiter.
Video

Video Scientists Say Plankton More Important Than Previously Thought

Tiny ocean creatures called plankton are mostly thought of as food for whales and other large marine animals, but a four-year global study discovered, among other things, that plankton are a major source of oxygen on our planet. VOA’s George Putic reports.
Video

Video Kenya’s Capital Sees Rise in Shisha Parlors

In Kenya, the smoking of shisha, a type of flavored tobacco, is the latest craze. Patrons are flocking to shisha parlors to smoke and socialize. But the practice can be addictive and harmful, though many dabblers may not realize the dangers, according to a new review. Lenny Ruvaga has more on the story for VOA from Nairobi, Kenya.
Video

Video Iowa Family's Sacrifice Shaped US Military Service for Generations

Few places in America have experienced war like Waterloo. This small town in the Midwest state of Iowa became famous during World War II not for what it accomplished, but what it lost. As VOA’s Kane Farabaugh reports, the legacy of one family’s sacrifice is still a reminder today of the real cost of war for all families on the homefront.

VOA Blogs