[url=https://www.sfgate.com/cgi-bin/article.cgi?f=/n/a/2009/01/13/international/i061837S07.DTL]Invasive Species Eradication backfired[/url], as reported in the San Francisco Chronicle.
Shows how important it is to judge the impact on your local environment of even something like household cats. I had a lively discussion over the holidays with someone who is an ardent environmentalist who nonetheless feels it's in his cat's best interest to be free roaming, even though he acknowledged his cat may be causing damage to the local bird and rodent population, which in turn might affect other species of animals and plants.It seemed like a good idea at the time: Remove all the feral cats from a famous Australian island to save the native seabirds.
But the decision... allowed the rabbit population to explode and, in turn, destroy much of its fragile vegetation that birds depend on for cover...
...The unintended consequences of the cat-removal project show the dangers of meddling with an ecosystem  even with the best of intentions