Large ranges in cat predation are primarily due due to the uncertainties in estimating how many owned and unowned domestic cats there are in the United States and how many actually hunt and catch birds. Research indicates it is possible to modify cat predatory behavior but wildlife and cat advocacy groups need to work together to produce successful policy outcomes.
Hadidian, John and Rowan, Andrew N.
"Revisiting the Cat Predation Issue,"
WellBeing News: Vol. 3:
2, Article 3.
Available at: https://www.wellbeingintlstudiesrepository.org/wbn/vol3/iss2/3