Russian President Vladimir Putin is reportedly planning to put on a fake beak and fly a motorised hang-glider to lead a flock of endangered Siberian white cranes on part of their migration to Asia.
The cranes, raised in captivity, do not know how to fly south, and environmentalists have to devise an imitation lead crane to show them the way.
Mr Putin's spokesman Dmitry Peskov told the Interfax news agency on Wednesday that the flight is to take place "one of these days".
The newspaper Vedomosti said it is expected before Mr Putin chairs the Asia-Pacific Economic Co-operation summit in Vladivostok beginning on Friday.
Mr Putin has become alternately notorious and beloved for an array of macho stunts, including posing with a tiger cub and riding a horse bare-chested.
Some of the stunts, such as petting a polar bear tranquillised in the wild, have purported scientific connections. But Mr Putin last year was caught out when one of the events was revealed to be a set-up.
In that case, he was shown scuba diving and bringing up fragments of ancient Greek amphorae. But Mr Peskov later admitted the artefacts had been planted on the sea floor for him to grab.
The stunts irritate Mr Putin's opponents, who regard them not as benign political entertainment but as part of an establishment of a cult of personality lionising an authoritarian leader.
Masha Gessen, author of a book critical of Putin, left her post as editor of the travel and science magazine Vokrug Sveta (Around the World) this week, claiming she was fired for refusing to send a reporter 2,200 miles (3,500 kilometres) north-west of Moscow to Yamal Peninsula to cover Mr Putin's flight with the cranes.
The magazine said she left by agreement with management because of "differences" on the separation of editorial and publishing powers.