Humans kill far more birds than feral cats. Agriculture, pesticides, deforestation, destruction of fields and grasslands, the use of mice and rat poison, car traffic, wind turbines, ... it all adds up. It makes feral cats look like amateurs showing up on a gun fight with a pencil.

In the EU, a 2021 study of 378 bird species estimated that bird numbers fell by as much as 19 percent from 1980 to 2017. And that's not because of cats, feral or not.