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

UN Report Exposes Widespread Boko Haram Atrocities

Damning report graphically details pattern of vicious, widespread atrocities committed by Islamist militants More

Russia’s Prosecutor General to Review Legality of Baltics Independence

Move, announced Tuesday, has alarmed Baltic States and strained even further their increasingly tense ties with Moscow More

US Urged to Keep Up Pressure on Cuba Rights

Communist government continues to hold dozens of political prisoners, tightly restricts freedom of expression, uses threats, intimidation to discourage critics, according to activist groups 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.
Hate Groups Spread Influence Via Interneti
X
Mike O'Sullivan
June 30, 2015 8:20 PM
Hate groups of various kinds are using the Internet for propaganda and recruitment, and a Jewish human rights organization that monitors these groups, the Simon Wiesenthal Center, says their influence is growing. The messages are different, but the calls to hatred or violence are similar. VOA's Mike O’Sullivan reports.
Video

Video Hate Groups Spread Influence Via Internet

Hate groups of various kinds are using the Internet for propaganda and recruitment, and a Jewish human rights organization that monitors these groups, the Simon Wiesenthal Center, says their influence is growing. The messages are different, but the calls to hatred or violence are similar. VOA's Mike O’Sullivan reports.
Video

Video US Silica Sand Mining Surge Worries Illinois Residents, Businesses

Increased domestic U.S. oil and gas production, thanks to advances known as “fracking,” has created a boom for other industries supporting that extraction. Demand for silica sand, used in fracking, could triple over the next five years. In the Midwest state of Illinois, people living near the mines are worried about how increased silica sand mining will affect their businesses and their health. VOA’s Kane Farabaugh has more in this first of a series of reports.
Video

Video Blind Somali Journalist Defies Odds in Mogadishu

Despite improving security in the last few years, Somalia remains one of the most dangerous countries to be a journalist – even more so for someone who cannot see. Abdulaziz Billow has the story of journalist Abdifatah Hassan Kalgacal, who has been reporting from the Somali capital for the last decade despite being blind.
Video

Video Texas Defies Same-Sex Marriage Ruling

Texas state officials have criticized the US Supreme Court decision giving same-sex couples the right to marry nationwide. The attorney general of Texas says last week's decision did not overrule constitutional "rights of religious liberty," and therefore officials performing wedding services can refuse to perform them for same-sex couples if it is against their religious beliefs. Zlatica Hoke reports on the controversy.
Video

Video Syrians Flee IS Advance in Hasaka

The Syrian government said Monday it has taken back one of several districts in Hasaka overrun by Islamic State militants. But continued fighting elsewhere in the northern city has forced thousands of civilians from their homes. In this report narrated by Bill Rodgers, VOA Kurdish Service reporter Zana Omer describes the scene in Amouda, where some of the displaced are taking refuge.
Video

Video Rabbi Hits Road to Heal Jewish-Muslim Relations in France

France is on high alert after last week's terrorist attack near the city Lyon, just six months after deadly Paris shootings. The attack have added new tensions to relations between French Jews and Muslims. France’s Jewish and Muslim communities also share a common heritage, though, and as far as one French rabbi is concerned, they are destined to be friends. From the Paris suburb of La Courneuve, Lisa Bryant reports about Rabbi Michel Serfaty and his friendship bus.
Video

Video S. Korea Christians Protest Gay Rights Festival

The U.S. Supreme Court decision mandating marriage equality nationwide has energized gay rights supporters around the world. Gay rights remain a highly contentious issue in a key U.S. ally, South Korea, where police did a deft job Sunday of preventing potential clashes between Christian protesters and gay activists. Kurt Achin reports from Seoul.
Video

Video Saudi Leaks Expose ‘Checkbook Diplomacy’ In Battle With Iran

Saudi Arabia’s willingness to wield its oil money on the global diplomatic stage appears to have been laid bare, after the website WikiLeaks published tens of thousands of leaked cables from Riyadh’s Ministry of Foreign Affairs. VOA's Henry Ridgwell reports.
Video

Video Nubians in Kenya Face Land Challenges

East Africa's ethnic Nubians have a rich cultural history that dates back thousands of years, but in Kenya they are facing hardships, including the loss of lands they have lived on for generations. They say the government has reneged on its pledge to award them title deeds for the plots. VOA's Lenny Ruvaga reports.
Video

Video Military Experts Question New Russian Tank Capabilities

Russia has been showing off its new tank design – the Armata T-14. Designers claim it is 20 years ahead of current Western designs - and driving it feels like playing a computer game. But military analysts question those assertions, and warn the cost could be too heavy a burden for Russia’s struggling economy. Henry Ridgwell reports.
Video

Video In Kenya, Police Said to Shoot First, Ask Questions Later

An organization that documents torture and extrajudicial killings says Kenyan police were responsible for 1,252 shooting deaths in five cities, including Nairobi, between 2009 and 2014, representing 67 percent of all gun deaths in the areas reviewed. Gabe Joselow has more from Nairobi.
Video

Video In Syrian Crisis, Social Media Offer Small Comforts

Za’atari, a makeshift city in Jordan, may be the only Syrian refugee camp to tweet its activities, in an effort to keep donors motivated as the war in Syria intensifies and the humanitarian crisis deepens. Inside the camp, families say mobile phone applications help hold together families that are physically torn apart. VOA’s Heather Murdock reports.

VOA Blogs