Lots of folks believe cats should be able to roam free, but the reality is that Felix Domesticus is a murderous invasive exotic. As much as I love cats I have given them up, since my allergies won't allow them inside and they have no business in an outside habitat. The "capture, spay, and release" movement confounds me. It's not just my problem but parks and preserves in many places are having to make choices. There is a great deal of disagreement as to what should be done.

Fort Oglethorpe Park has taken to prosecuting people who feed feral cats.

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Here are the findings of a very good study:

We estimate that free-ranging domestic cats kill 1.3–4.0 billion birds and 6.3–22.3 billion mammals annually. Un-owned cats, as opposed to owned pets, cause the majority of this mortality. Our findings suggest that free-ranging cats cause substantially greater wildlife mortality than previously thought and are likely the single greatest source of anthropogenic mortality for US birds and mammals

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