Ecologists talk a lot about invasive species. These are plants and animals that are not native to North America, and cause enormous economic and ecological damage when they establish. Examples include cane toads, kudzu, zebra mussels, and fire ants.
Most invaders are easy to malign. No one is lobbying to protect the rights of killer bees or starlings. But if you are among the 33% of Americans that owns a house cat, you won’t be pleased to hear that, if allowed to roam outdoors, your beloved companion is a threat to the environment.
Even more problematic are the millions of feral cats that have been abandoned. Some cities and suburban areas record hundreds of cats per square mile. There are simply more cats than nature can support, and these cats are remarkable successful predators, killing about a billion birds each year in the United States.
Along with pythons in South Florida and feral pigs in the Great Smoky Mountains, cats have no place in nature. They threaten some of the endangered species we are working so hard to reestablish. Ron Jurek of the California Department of Fish and Game comments: ((Cats kill one or two colonies of least terns each year. These small white birds are part of an intense monitoring program with volunteers who watch the colonies throughout the six-month nesting season.))
Humans have been enjoying feline companionship for more than 9,000 years. I am not suggesting this relationship should end. But responsible pet ownership – including spaying and neutering – is needed to minimize the number of cats that roam, and thus the number of birds that are silenced.