每年家猫吃掉的野鸟上亿只以上，我有个印象是野鸟最大的天（人？）敌。Keep them indoor, please.
狗一下，起码是一亿只鸟。：Estimates of total annual kill of birds by house cats ranged from 105 to 348 million per year (95% of estimates), with 56% of estimates between 150 and 250 million (Fig. 2, Table 4).
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