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Do feral cats have special needs, or is their plight all in our heads?

  • Author: Rick Sinnott
    | Opinion
  • Updated: June 21, 2017
  • Published June 21, 2017

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A local "rescue group for animals with special needs" wants to change the state law that prohibits releasing domestic cats into the wild. Mojo's Hope is also seeking permission to establish and maintain colonies of feral cats in Alaska communities.

Why just cats? Why not release dogs, snakes, canaries, goldfish and other household pets into the wild? It might be because cats have deployed a secret weapon.

Do feral and stray cats have "special needs," or is their plight all in our heads?

Feline mind control

Tiny parasitic wasps of the tongue-twisting genus Glyptapanteles practice mind control on their hosts. Females deposit their eggs into caterpillars. The eggs hatch into wriggly larva, which feed on the caterpillar's bodily fluids until up to 80 of them erupt through its skin.

Here's the creepy part. One or two larvae from the brood remain inside, releasing chemicals that hijack the caterpillar's brain, compelling it to stay nearby and defend its parasitic "progeny" from predators.

The caterpillar even helps encase the pupal cocoons with its own silk. Finally, as the wasps complete their life cycle and emerge from their cocoons to fly off as adults, the caterpillar dies of starvation.

That's awful. But, hey, it's just a caterpillar.

Similarly, research has shown that a single-celled protozoan parasite found in cat feces alters the brain chemistry of rats and mice until their fear of cats morphs into an attraction, a kind of aphrodisiac. When the parasites are in control, rats and mice are attracted to the smell of cat urine.

Infected rodents don't last long in the presence of a cat and their consumption ultimately results in a bowel movement that contains thousands of microscopic oocysts, the parasite's infective stage, thus completing the cycle.

Oocysts are extremely persistent in the environment and can exist for months or years in soil or water.

It's important to note that, while there are many intermediate hosts, the only creature in which Toxoplasma gondii can reproduce sexually –- the definitive host –- is a member of the cat family.

Cats are largely unaffected by toxoplasmosis; they transmit the parasite to the rest of us.

Rats and mice are used as proxies for drug testing and other research because their brains are not so different from ours.

So it's not a complete surprise scientists have discovered the same behavioral changes associated with toxoplasmosis in rats and mice – reduced anxiety, fearlessness and an attraction to cat urine – are also expressed in humans infected with the oocysts, according to Peter Marra and Chris Santella, authors of "Cat Wars: The Devastating Consequences of a Cuddly Killer."

This finding may help explain the behavior of cat hoarders, people who seem unable to resist the urge to keep taking more in, even though their home is already overrun with dozens of cats and reeking of urine.

'Cat hoarding without walls'

One of the world's most common parasitic infections, Toxoplasma gondii infects approximately 1 out of 3 humans. Fortunately, most of us don't succumb to the urge to hoard cats. But a large and growing number of cat aficionados would like to change the rules that govern how cats, particularly feral cats, are managed.

Rather than rounding up feral cats and euthanizing the ones that cannot be adopted out, these feral cat advocates want to establish cat colonies where cats are fed outdoors until they die of natural causes. Proponents like to call them "community cats," as if we are all responsible for feral and stray cats.

The concept is called trap-neuter-release or TNR. Feral and stray cats are attracted to feeding stations, captured in live traps, neutered and vaccinated, and returned to the capture site.

Feeding stations are maintained until all the cats have died. The hope is breeding will end and the cats will lead healthier lives.

However, because 71 percent to 94 percent of a population must be sterilized, with no immigration, to reduce its size – and because people constantly release cats into the wild – managed cat colonies can persist for decades, if not forever. Ecologists questioning the TNR approach's lack of a feasible exit strategy have called it "cat hoarding without walls."

Nationally, TNR is being pushed by Alley Cat Allies. Mojo's Hope, with support from Alley Cat Allies, approached Anchorage's Animal Control Advisory Board several years ago, asking for permission to establish a TNR program in the city. The group was advised that the state prohibits the release of cats into the wild.

Now Mojo's Hope has submitted a proposal to the Alaska Board of Game to change that law. The organization hopes to remove cats from the list of domestic animals and pets that cannot be released into the wild without a permit.

Intermittent explosive disorder

Unfortunately, the parasites that imbed themselves in our brains and alter our behavior are broadcast throughout the environment via cat feces. Researchers have found as many as three to 434 oocysts per square foot in soils, and the oocysts are washed into lakes, streams and the ocean.

Places where cats prefer to defecate, like the loose soil of gardens and children's sandboxes, tend to have the highest oocyst counts. But you don't have to play in a sandbox and put your fingers in your mouth to become infected.

The parasite can be ingested from aerosolized cat feces in settings like horse barns inhabited by "barn cats" and by drinking contaminated water.

If toxoplasmosis merely fostered a desire to fondle kittens, it would be harmless. But the parasite seems to have much more pervasive and unfortunate consequences to public health. At least 80 studies have linked toxoplasmosis to schizophrenia and related psychoses.

Toxoplasmosis has been linked to an anger-management behavior called intermittent explosive disorder, and infected humans are twice as likely to be involved in a car accident.

Women with toxoplasmosis were 54 percent more likely to attempt suicide, and twice as likely to succeed. The risk of suicide was much higher for women with higher levels of antibodies, and infected women with no prior history of mental illness were at higher risk than those with no exposure.

TNR advocates ignore or object to this research. Instead, they refer to a handful of studies that find little or no evidence of mental disorders following toxoplasmosis. A recent long-term study in New Zealand, for example, found no correlation between exposure to cats as a child and subsequent mental illness.

But in that study "long-term" meant only to age 38. Most of the truly crazy people I know are older than that.

There seems to be no argument over the affect of toxoplasmosis on human fetuses. If a woman contracts the disease while pregnant, and fails to get treatment, the infection may result in miscarriage, stillbirth or death shortly after birth.

Congenital toxoplasmosis can affect a baby's brain, causing mental or motor development delays, cerebral palsy and epilepsy. It can also lead to visual impairment and sometimes blindness. Serious stuff.

The current theory is that most cases of toxoplasmosis are not the result of emptying litter boxes, but from eating uncooked or undercooked meat. A TNR advocate is likely to cite this statistic as evidence that feeding feral cats, or accidentally ingesting the parasite outdoors, is not a problem.

But remember, cats are the sole primary host. All the oocysts in soil and drinking water and the oocysts that find their way into the meat we eat are from cats. The more cats are allowed to eat birds and rodents, and defecate outside, the more oocysts will be in the environment to infect humans and other animals.

Other diseases transmitted from cats to humans include hookworms, cat scratch disease, murine typhus, tularemia, plague and rabies.

Despite the best efforts of cat colony managers, feral cats tend to be more diseased than pets kept indoors.

Who else eats cat food?

More than 300 communities in the Lower 48 states have adopted TNR programs, and some cities support hundreds of cat colonies.

TNR is a bad idea. We don't need more feral and stray cats, we need far fewer.

Alaska presents several unique hurdles.

Imagine a cat colony in your neighborhood. Bears eat cat food and can be expected to be attracted to places where food is provided for feral cats. Do you want to give anyone an excuse to attract more bears into your neighborhood?

Don't bears have special needs too?

Feeding bears is illegal without a permit. Is the Alaska Department of Fish and Game going to authorize cat colonies that also feed bears, creating more food-conditioned bears in communities?

Before we all succumb to the mind-altering parasites lurking in cat feces, can we stuff this proposal by Mojo's Hope into a burlap sack and drop it off the nearest bridge?

Rick Sinnott is a former Alaska Department of Fish and Game wildlife biologist. The views expressed here are the writer's own and are not necessarily endorsed by Alaska Dispatch News. Contact him at

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