With the increasing interest in bird feeding and attracting wildlife to the backyard, along with the number of cats that spend at least part of the time outside, cats are getting a bad reputation. Bird lovers are justifiably upset when a cat comes into the yard and hunts the birds that they are attracting, or even if it just scares them away. Articles have been written in birder magazines claiming that cats are killing millions of birds every year, threatening to wipe out whole populations. As with so many things these days, positions harden, people become emotional and hostile to those with an opposing opinion, and the facts get ignored or twisted to support a point of view. So what are the facts? This is where it gets tricky.
Cats are predators, genetically programmed to hunt and kill prey, and they kill birds, no one denies that. The question is, how many? Estimates always start in the millions, many millions, of birds. Estimates we found started at 40 million birds killed each year by cats, and topped out at 4 to 5 million killed each day, which comes to between 1.4 and 1.8 billion birds killed each year by cats. The high estimate came from an internet site, so it has no validity at all, but the person(s) who placed it there believed it.
The number of cats owned by Americans is estimated to be about 65 million, with about half of these being ‘indoor only’ cats who never go outside, and the other half spending part or all of the time outside. In addition, there are homeless cats, those that have gotten lost, or tossed out, or left behind when the owner moved. In many cases, these cats join together with other cats in like circumstances, and form a group, or colony, and gradually become wild again. They and their offspring live off the land, hunting and scavenging for food. It is estimated by some that the number of these feral cats, as they are known, is equal to the number of cats that are owned. If that is true, when you include the owned cats that spend time outside, you have about 100 million cats that spend time hunting wildlife.
Feral cats get blamed for killing a lot of wildlife, since they need to hunt in order to eat. Many people think that they are largely responsible for a decrease in the number of wild birds that seem to be around. While there is no doubt that cats do kill birds, the number that they do kill is difficult, if not impossible, to determine. If actual surveys are attempted, they are done on small groups of cats, and the results from the survey are extrapolated onto the entire estimated population of outdoor cats. The resulting figures include a lot of guesswork, and estimates that vary widely.
There are a number of reasons to indicate that cats may not be the mass murderers that they are portrayed to be. As Dusty learned, hunting birds is not easy. They do not stay in one place for long, but hop about looking for seeds or insects. Cats prefer to hunt prey that stay in one place long enough for them to prepare the attack. Also, birds will observe the ground from a perch, in order to spot predators that might be lurking about. Rodents, on the other hand, are much easier for a cat to catch. They are slower, they can’t fly away, and when they find a food source, they stop and eat until the food runs out or they are full, giving a cat plenty of time to pounce.
Cats are opportunistic feeders, and will learn to find the easiest source of food. This may explain why there are always cats living behind restaurants. The dumpster provides a surer source of food than a meadow or woodland area, and cats that are left behind at apartment complexes soon find their way there.
Birds that nest on the ground are more likely to be preyed upon by cats than tree nesting birds, although some cats will climb a tree and wipe out a nest. Some people forget that there are a lot of other predators out there who make birds and their nests part of their diet. Raccoons spend a lot of time in trees, and if they come across a nest of eggs or young, it becomes a meal. On the ground, raccoons, fox, weasels, skunks, possum, and in some areas coyote and bobcat all hunt for ground nesting birds. In the trees, blue jays, starling, and crows destroy more nests than any other predator. On the wing, birds are most at risk from certain types of hawk, falcon and owl, all of who make songbirds a part of their diet, and consider a bird feeder an open buffet.
Feral cats are a problem, and a topic for an article in a future issue, but to blame them for the decrease in the number of songbirds in certain parts of the country seems a bit of a stretch. A more likely explanation is in the constant loss of habitat, both here and in South and Central America, where they spend the winter. Around fast growing cities, acres of prime bird habitat are wiped out every day for development, leaving less and less area for the birds to live.
