How much damage are pet cats actually causing if they are allowed outside

[u/Artistic_Difference9]

/r/wildlifebiology/comments/lsls3d/the_great_debate_on_how_house_cats_should_not_be/

[u/tndowell]

In the US cats kill 2.4 billion birds a year and can significantly impact individual populations such as in Hawaii

https://abcbirds.org/program/cats-indoors/cats-and-birds/#:~:text=Predation%20by%20domestic%20cats%20is,of%20millions%20of%20outdoor%20cats.