The impact of free-ranging domestic cats on wildlife of the United States

Loss, Will and Marra produced a landmark quantitative estimate of how many wild animals free-ranging cats kill in the United States. Synthesizing data from predation studies through a systematic review and statistical modelling, they estimated that cats kill on the order of 1.3 to 4.0 billion birds and 6.3 to 22.3 billion mammals annually, with un-owned feral and stray cats responsible for the majority. The analysis identified free-ranging cats as likely the single greatest direct anthropogenic source of mortality for US birds and mammals, far exceeding causes like collisions and poisoning. The paper galvanized conservation concern and policy debate over cat management, demonstrating the scale of predation through rigorous extrapolation and underscoring the ecological stakes of free-roaming domestic cats at a continental level.