In a square in central Warsaw, a couple of people are bent over a huge sculpture of a blue egg, their heads turned and pressed against the shell.

As they listen to the soft sounds of a baby bird hatching, a hooded crow cocks his head and sips from a shallow pool of water installed nearby.

"This chick and the mini-pond next to it speak to a sensitivity to Warsaw's non-human residents," Warsaw deputy mayor Aldona Machnowska-Gora said at the unveiling.

"Don't hesitate to walk up to the egg and hug it. It makes for an incredible experience," she said.

Located at Five Corners Square -- once home to an arena where animals would fight to the death -- the acoustic installation titled The Hatchling is a call for empathy with other lifeforms in the era of climate change.

"The idea was to bend people's bodies over something other than themselves," said Joanna Rajkowska, the artist behind the sculpture.

"We care about our well-being so much. It's like a complete obsession... It's time to think about other species," she told AFP.

'The Hatchling speaks'

At around two metres (6.6 feet) high and three metres long, The Hatchling is a larger than life version of a song thrush's blue spotted egg.

The colour is more intense than the real blue because the sculpture will inevitably fade in the sun.

"Inside, instead of a bird, we have a lot of electronics, a lot of circuits and sound transducers... So The Hatchling speaks," said Rajkowska.

"Literally, like pecking the shell. But also the heartbeat, which is three times faster than the human heart. You can also hear all the movements and the chirping," she added.

"So it's a whole spectrum of sounds. Basically the desperate life that is trying to get out of the egg."

She teamed up with her musician partner for the recordings, though they do not come from a song thrush, as the stress of the process would have been enormous for a wild bird.

"An ornithologist told me that if I take an egg from the nest and then return it, the parents will not accept it... So I decided to find safe conditions," Rajkowska said.

They came across "this crazy guy who is trying to revive old species of chickens" who allowed them to record in his lab as long as they kept the eggs warm.

"So we had to really rush to do the recording and put it back in the incubator," Rajkowska said.

'Surreal, unexpected'

The artist is also the creator of a massive fake palm tree that has for years added a tropical note to the Polish capital and even become a popular postcard landmark.

Similarly, the egg -- whose top is already speckled with bird droppings, to Rajkowska's amusement -- is meant to be "surreal, unexpected and slightly out of touch with reality".

Piotr Nowacki, a life-long Warsaw resident, is a fan of the project, which he has visited several times and calls "a break from routine, somewhat abstract, surprising".

"It also educates (and) draws your attention to nature... It's cool that it's dynamic, that it's alive, right?" the 36-year-old software engineer told AFP.

Rajkowska has also exhibited a series of collages juxtaposing old and new magazine clippings, old photographs of the plaza -- and birds, of course.

"I love that they evolved from the dinosaur and they have such a long, long history... And we make their habitats smaller and smaller and smaller. We concrete everything," Rajkowska said.

"The Hatchling is actually a sad project. It is tinged with disappointment but also with hope that we mature enough to see beyond ourselves."