Spotting

Feral Pigeon

"Columba livia" is the correct scientific name, sub-species domesticus.

I remember checking into this about 10 years ago and it was a thing then too.
Here's what's going on in Spain where "..the eccentric world of Spanish pigeon racers, who hand-paint their birds in neon colours and send them off to woo a female. The champion pigeon is the one that woos most chivalrously"
https://www.theguardian.com/artanddesign...
What we can say is this pigeon probably belongs (or belonged) to someone.

Hi Tarwin and welcome to Project NOAH, and I hope you will be able to fully enjoy the site. Project Noah is a tool for people to learn about wildlife, share wildlife spottings, build nature journals and engage in citizen science. Here you will find a friendly community of people passionate about wildlife and conservation.

I covered your spotting temporarily (and will revert to you shortly) as the practice described in comments is not something we encourage. You may want to visit our FAQ section here: https://www.projectnoah.org/faqs , in order to check what kind of spotting we encourage.

We hope you enjoy our website and community as much as we do! Enjoy yourself, learn, share and see you around.

Cheers
Zlatan

Probably captured, dyed, banded and released
This often happens when bird traders want to fool gullible people. Why banded and released is not clear. Ihave seen munis birds coloured like this.