Rover dressed as a penguin aids conservation

It looks comical - a remote controlled car zipping around a penguin colony dodging irritated snaps from the birds.

But using the diminutive vehicle to study penguins, researchers have found, has has much less impact on their behaviour than being approached by a human.

Scientists say the unusual approach provides "a less invasive and stressful way to collect data on these species".

These findings are published in the journal Nature Methods.

In part of their study, the researchers even disguised one rover as a penguin chick in order to access a colony of notoriously nervous emperor penguins.

Dr Yvon Le Maho from the National Centre for Scientific Research in Strasbourg, France, led the study. He first decided to test the rover after he found that traditional flipper tags compromised the health of penguins.

To avoid these "unethical" flipper tags, the researchers began using tiny transponders - tags implanted under the birds' skin - to monitor a colony of king penguins on Possession Island in the South Indian Ocean.

But - just like the microchips often used to "identichip" pets - reading data from these tags requires them to be scanned up close using a receiver.

"I wondered if it might be possible to use a technological device to do this, and I thought about a rover," Dr Le Maho told BBC News.

He and his colleagues measured penguins' heart rates when the vehicle approached and when a human researcher approached.

"There was a very high increase in heart rate with the human - much more than in a rover," he explained.

Lunged and snapped

This reaction to people is exacerbated by the fact that, when the birds are incubating eggs, "they won't move".

The approach of the little vehicle certainly seemed to irritate the birds, which - as footage revealed - waited until the rover came close, then lunged and snapped with their beaks and flippers.

"But when the rover stops, even within the territory of the birds, they don't pay any attention to it," said Dr Le Maho.

In fact when the team measured the increase in the birds' heart rate when the rover approached, the found it was about the same as when another bird passed by.

"It's very much higher when a person [approaches]," said Dr Le Maho

"Even if the human is motionless, they still have a very high heart rate. And [it only returns to normal] more than five minutes after the human has left."

Spy in the huddle

In the second part of their research, Dr Le Maho and his colleagues wanted to see if they could use their rover to study the very shy emperor penguin.

"Emperors huddle together, because they have no [other] territorial defence," the scientist explained. "So when they see the rover approaching, they get very stressed.

"So we thought, what if you camouflage the rover - disguise it as a chick."

The researchers worked with the team of nature filmmakers, who produced the penguin documentary Spy in the Huddle.

This resulted in an even more a comical-looking rover, with a fake chick sitting on top, which the researchers used to infiltrate the colony.

But the disguise was effective; the emperor penguins allowed the rover to approach close enough to read their tags. Some birds even interacted with it - vocalising at the fake chick.

"Scientists do not generally speak about disturbance they cause," Dr Le Maho told BBC News.

"But I have always been very concerned with that - it relates to both science and ethics."

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