Trapping Cats: Part 1: Why we should.

Predator Control: Be strong, families. You can do this.

Reasons to trap cats:

Definition: “Stray” (noun) domestic animal that is wandering at large.

There are over 60 million pet cats in the US many of which roam loose, plus there are 70 million feral cats that are all strays. Getting them out of your yard is about more than just protecting the birds.

[To be clear: We’re talking about live trapping cats in sections 1 and 2.]

The most controversial thing I write about isn’t the Israeli Palestinian conflict. It isn’t racism. Or the drug war. Or my contention that we need to bring back home economics and shop class to schools more than we need more math and science. Nope. The most controversial thing I write about is trapping stray cats. There’s  biological reason for that which we will talk about shortly.

Most people get into trapping cats to save birds, squirrels, and other wild life. That’s a good reason. Research scientists at the Smithsonian Conservation Biology Institute and the US Fish and Wildlife Service estimate outdoor cats kill an estimated  1.3 to 4.0 billion birds and 6.3 to 22.3 billion mammals every year in the United States alone.  For those who don’t care about wild animals, there are other compelling reason to trap cats. Diseases they pass to humans all over the world for instance but let’s start with cat predation.

Reason 1. Cats are not a natural part of our ecosystem: In fact, they are on the List of the World’s 100 Worst Invasive Alien Species.

Cats are a wrecking ball in the environment. The numbers of other animals they kill are astonishing. In addition to birds, cats kill mice, voles, bats, squirrels, insects and any other small thing that moves. Cat predation disrupts the balance of nature not only by killing off wild animals, but by taking prey that should feed wild predators that are natural and essential to a given ecosystem.

There are thousands of articles, both scholarly and mainstream, documenting the carnage cats cause. You can read about remote islands all over the world where cats wiped out bird colonies and on some islands drove bird species that lived only there to extinction. They’re gone forever. Australia’s unique wildlife has been annihilated over large areas. We’ll talk about that in section 3 but the take away from The Land Down Under is, millions of wild cats have killed so many indigenous animals that the state of Queensland put a bounty on them and Aboriginal hunters are going after cats to save wildlife that Aboriginal society has relied on for 60,000 years.

I got into trapping cats because of the birds. When we bought our place  back in the ’90’s the neighborhood was overrun with cats and a crow colony that ate fledglings like peanuts. There were no songbirds to sing in our trees. I found a way to drive the crows away without killing them (blow gun with paintballs). But the cats were and are an ongoing problem. We’d see cats walking through the yard all the time and find bird parts: a wing here, a torso there, especially ground nesting baby birds  like varied thrushes in spring. One day I found a dead sharp shinned hawk in the yard and said, “That’s it.” Bought a Havahart Live Trap, took nine cats to the animal shelter in the first 30 days. Over the years I’ve taken 79 to the shelter. (All but two from our yard. The other two I trapped for an old woman who was afraid they’d kill the squirrels in her yard.) Now we have birds singing in our trees. I take a little credit for that.

Cat borne diseases: handle with care

Reason 2. Cats are the essential intermediate host of a parasite that infects the brains of over two billion humans in the world including over 60 million Americans

Toxoplasma gondii, is a protozoan related to those tiny things  you remember swimming around under the microscope from high school biology class. This thing rewires mammal  brain chemistry to be, among other things, attracted to cats. Why do people who claim to be animal lovers let cats stray outdoors when they know cats are wiping out bird species? Why do such people fight efforts to remove stray cats from wild animal sanctuaries? Why are there cat ladies with thirty cats living all over their houses, eating food on the table, pissing and shitting all over the place? Well, odds are good that those peoples’ brains have been hijacked by this parasite that was shat out by their cats.

T. gondii has multiple stages in its life-cycle. One of those stages needs to pass through a cat’s gut as an intermediate host on its way to infect other mammals. That means cats are the definitive host for the parasite. As I understand it, something about a cat’s gut chemistry keeps the parasite from messing up the cats. Other animals though, can be profoundly compromised. This is a good reason to wash your hands before lunch if you’ve been in the garden or sandbox. Once it is accidentally ingested into an animal’s stomach, toxoplasmosis migrates to the body tissues, including the brain, where it forms cysts that stay there indefinately. At this time an estimated 20% of Americans (60 million men, women and children) are affected.

In 2012 there was a nice article in the Atlantic about Czech researcher Jaroslave Flegr working mostly on his own, who figured this out through years of elegant experiments. He found  that when there’s cat urine in the corner of a room mice that aren’t infected with T. gondii will get as far away from it as they can. Which is expected. But mice that are infected with T. gondii are attracted to cat urine. That’s the payoff to cats for being the middle host. Mice brains infected by the parasite become hijacked causing the mice to lose their natural fear of cats and approach them to be eaten. The cat gets an easy meal. More than that, T. gondii changes the brain chemistry of a rodent’s anxiety and sexual responses.

Cat feces is full of T. gondii cysts. Researcher Dr. Rima McLeod notes an infected cat can shit out 500 million oocysts in two weeks.  Other animals, including people, ingest the cysts incidentally. People can also take in cysts from eating undercooked meat. Again, once cysts of this parasite find their way into another mammal they travel to neural tissue in the brain or eye cells where they usually go dormant and stay forever unless/until the immune system gets weakened by a virus or other disease. Then the parasite can reactivate and resume doing damage.

Toxoplasma  gondii diseases in humans:

Birth Defects:  Expecting mothers infected with T. gondii can pass the infection to their unborn child with terrible effects like brain damage, blindness, hydrocephalie, and other lifelong damage. That’s why expecting mothers aren’t supposed to clean a cat litter box in case they should inhale spores or get oocyst contamination on their hands.  Contamination can also happen when mother is working in a garden bed where stray cats have shit.  Even one oocyst can infect a pregnant woman. When pregnant women are infected, especially  in the first trimester, the infection can cause serious damage.

Ocular Toxoplasmosis: the most common eye inflammation in the world. It attacks the retina at the back of the eye. The disease may resolve or it may appear to resolve but the parasite may remain inactive in the eye then, for a variety of reasons can reactivate causing blurred vision, loss of vision, macular damage, scarring of the optic disc, and other damage, including potentially blindness.

Mental Health diseases: as Yogi Berra said, “Sometimes you can observe a lot by just watching.”Toxoplasmosis used to be considered mostly a benign parasite.  Science paid it scant attention. In the past ten years there has been increasing study of the parasite’s ability to affect mammal behavior through chemical changes like increased dopamine levels. Living in the brain as it does, scientists today are studying possible connections related to a raft of mental health disorders: Schizophrenia, Autism, ADHD, OCD, Anxiety, Antisocial Disorders, Dementia, Alzheimer’s, Dementia, learning disorders, and Intermittent Explosive Disorder (IED)–someone had fun naming that one. It turns out that people with rage disorders prone to outbursts like road rage, are twice as likely to be infected with Toxoplasmosis as people who aren’t infected. Other studies have shown that infected people are more likely to get into car accidents.
The dormant parasite cysts living in the brain are kept in check by a constant response from the immune system-which usually works fine as long as you’re young and have a healthy immune system. As people age, or if their immune system is compromised by disease, the dormant cysts can reactivate.

Death: Here’s a quote from the Center for Disease Control: “Toxoplasmosis is considered to be a leading cause of death attributed to foodborne illness in the United States.” It is on the CDC’s list of five neglected parasitic infections of the United States.

There are dueling narratives in the literature. Cat people will point out people also get the parasite through drinking water contaminated with T. Gondii or from eating undercooked meat, shellfish and some fin fish species that are contaminated. Cat lovers also point to a few studies claiming cat ownership doesn’t automatically mean mental illness among the owners. Cat lovers take these things as proof that cats aren’t the problem. These claimants gloss over the fact that felines are the definitive host for this parasite. When other animals ingest oocysts, say cattle drinking from a contaminated water trough, the cysts migrate into the animals’ muscle tissue, when you eat those muscles, the cysts go down the hatch as well.

Other Cat Diseases:

Cat Scratch Disease: Bacterial infection baroinella hensela transmitted to human lymph nodes.

Pasteurella mulocida: Bacterial infection from cat bites. 90 percent of healthy cats have this bacteria in their mouths. (New York Times) There are and estimated 400,000 cat bites resulting in 66,000 hospital visits in the US each year. (World Health Organization) Relatively few of these end up being admitted to the hospital.

Rabies: Between 2017 and 2018 rabies in America among all animals increased 11%.  Cats are part of that. Cats, both domestic and feral, are increasing. They fight with each other, fight with other animals, and eat other animals. This, and the fact that  a lot of people aren’t getting their cats vaccinated, puts cats at risk for rabies.

Cat transmitted diseases that affect other animals:

Feline leukemia: Estimated 30 percent of stray cats have feline leukemia. It’s highly infectious to other cats but not people. For people who have cats, this is a reason to keep them indoors.

Pasturella (again) For birds and small mammals pasturella from cat bites is often fatal. My friend Irene, who has been rehabbing sick and injured birds for decades says it often happens that a bird injured by a cat will seem to get better for two or three days only to die of pasturella-caused septicemia

Toxoplasmosis gondii kills marine mammals: This one was a surprise. T gondii has killed pinnepeds (seals and sea lions),  otters, and even whales. The mechanism of how it gets so far out into the marine ecosystem and how prevalent it is, is unclear.  What is clear is that marine mammals are particularly sensitive to toxoplasmosis. Don’t flush cat poop down the toilet or let cats roam beaches and estuaries.

Reason 3. Stray cats live shorter lives: because they’re more susceptible to diseases like feline leukemaia and feline immunodeficiency virus, infections, parasites like fleas, lice, ticks, worms; being attacked by other animals including dogs, other cats, coyotes (cats make up 20% or more of Los Angeles coyote diets), getting hit by cars causing death, broken bones,and internal injuries; eating or drinking poisonous stuff like rat-bait or anti-freeze.

Undernourished stray in tough shape.

Reason 4. If I step out the back door with our little dog, and there’s a cat out there, she’s likely to chase it. That’s what dogs do. Ours usually comes when she’s called but if she ran into the road chasing a cat and was killed, I’d blame myself if I hadn’t tried to get rid of the cats.

Reason 5. They shit in your vegetable garden,  piss under your deck, on your packages that the mail carrier leaves on your porch. Health risks aside, it’s disgusting. Stories about these in part 5.

Reason 6. A mob of cats just killed your chickens. We’ll talk about that in part 5, too.

Reason 7. A cat lady died leaving 30 or so cats. You bought the house. Cats are still hanging around. See part 5.



03.2012  How Your Cat is Making You Crazy? The Atlantic by Kathleen McAuliffe

0.22.2014 What does it mean when 2 million people share their brain with a parasite? University of Chicago Medicine by John Eaton.

12.02.2016 Ocular toxoplasmosis: National Center for TranslationalSciences

Toxoplasma gondii US Center for Disease Control