My cat brought a fledgling in, have I done the right thing?

you did what you thought was right, well done you, i have 4 cats, and so far none of them have brought any fledglings home[yet], but there are a pair of magpies that have attacked 2 of my cats in the garden , and they are really vicious, so i,m hoping they can prevent my moggies raiding any nearby nests this year...i have 2 bells on each of my cat,s collars to give the birds a fighting chance.