Trev's had enough of the sparrows. Apart from nesting in the eaves and making a mess (which we tolerate for native species) they outcompete small native bird species, eat the chook food, peck holes in our vegie greens, eat raspberries, pull out seeds and even small seedlings and we have hundreds and hundreds of them. And in the past years they've been the vector for strains of salmonella that has passed from birds to other species.
They're non-native having been introduced in 1862 (though one would assume that their descendants should be able to claim nationality by now?)
Trev looked up traps and found this plan. The guy who build it claims to have wiped out his sparrow population with no by catch. We're not interested in wiping them out, only reducing their numbers in order to allow native birds to co-habitate. The trap doesn't kill them, only catches.