A pair of barn owls can consume over 2,000 native or invasive mammals per year. It has long believed that barn owls diet consisted of rats and mice but new research has found that their diet is actually made up of 85 per cent shrews and voles (easier to catch then rats and mice), and 12 per cent mice and 2 per cent rats. Because their diet only includes 2 per cent rats the likelihood that they will be injured by second hand poisoning is far less than once believed. Now it has been revealed that Norway rats and house mice are only a small percentage of the diet of owls, as they will consume a wider variety of invasive mammals. The study proves barn owls will take advantage of altered conditions presented by new arrivals of mammals: birds are adaptable to prey that is available regardless if the prey is native or invasive, and it shows these owls are flexible enough to survive with important variations in habitation and food supply.
