A blue-and-yellow macaw, believed to be the only wild macaw left in Rio de Janeiro, has been spotted visiting the city’s zoo nearly every day to try to find a mate.

The bird, named Juliet, has appeared at the BioParque’s macaw enclosure almost every morning for the last two decades.

Blue-and-yellow macaws live to be about 35 years old and Juliet – no spring chicken – should have found a lifelong mate years ago, according to Neiva Guedes, president of environmental group the Hyacinth Macaw Institute.

But Ms Guedes said Juliet has not paired, built a nest or had chicks, so at most she is “still just dating”.

She said: “They’re social birds, and that means they don’t like to live alone, whether in nature or captivity. They need company.”

She added Juliet “very probably feels lonely, and for that reason goes to the enclosure to communicate and interact”.

Apart from Juliet, the last sighting of a blue-and-yellow macaw flying free in Rio was in 1818 by an Austrian naturalist, according to Marcelo Rheingantz, a biologist at the Federal University of Rio de Janeiro, and there are no other types of macaws in the city.

Being boisterous with brilliant plumage helps macaws find each other in dense forest, but also makes them easier targets for hunters and animal traffickers.

Brazil Rio Macaw Love
Juliet, left, grooms with a captive macaw at BioParque (Bruna Prado/AP)

They are often seen in other Brazilian states and across the Amazon, and it is suspected Juliet escaped from captivity.

Last year, BioParque gave its macaws more space: a 1,000-square-metre (10,700 sq ft) aviary which they share with green parrots and golden parakeets.

BioParque reopened to the public in March, after privatisation of Rio’s dilapidated zoo and almost 17 months of renovations.

The facility aims to feature species associated with research programmes at universities and institutes.

One such initiative is Refauna, which reintroduces species into protected areas with an eye on rebuilding ecosystems, and is participating with BioParque to start breeding blue-and-yellow macaws.

The plan is for parents to raise some 20 chicks that will receive training on forest food sources, the peril of predators and avoidance of power lines.

Brazil Rio Macaw Love
Juliet is believed to have escaped from captivity (Bruna Prado/AP)

Then the youngsters will be released into Rio’s immense Tijuca Forest National Park, where Juliet has been sighted and is thought to sleep each night.

Mr Rheingantz, the programme’s technical co-ordinator, said: “Their role could be important in terms of ecosystem and reforestation.

“It’s a big animal with big beak that can crack the biggest seeds, and not all birds can. The idea is for it to start dispersing those seeds, complementing forest animals that can’t.”

After some pandemic-induced delays, the project has slowly restarted and Mr Rheingantz expects to release blue-and-yellow macaws into Tijuca park towards the end of 2022.

After two decades of relative solitude, Juliet will then have the chance to fly with friends.