Rodenticide: Feral CatsÔÇÖ Biggest Enemy

There are numerable hazards that face our feline neighbors who live outside.  Although cars are very dangerous, cats can learn to avoid them. However, one hazard which outdoor cats may be particularly susceptible to is poisoning by rodenticides.  Rodenticides are available in forms that look and taste exactly like cat food on store shelves. Some types are particularly dangerous for outdoor cats, and itÔÇÖs our job to protect all of our animal friends – including cats, birds, dogs and other unintended victims of rodenticide.  This is particularly true for Detroit Alley Cats because one of our favorite cats, Zorro, was killed by rodenticide poisoning.

Zorro, the ambassador to the alley cats

Zorro was a very friendly outside cat that lived in the neighborhood. The neighbors raised him from a bottle as a kitten after his mother was hit by a car.  He preferred to be outside and would only come inside for a short time before politely asking to leave. He was known to several of the neighbors to greet them when they left in the morning or when they came home in the evening.  He was also the ambassador to the alley cats, and many strays who would not allow humans to approach would stand fast in his presence. Zorro was well accustomed to cars and would look both ways before carefully crossing the street.  Detroit Alley Cats neutered him on behalf of his family as he spent most of his time outside. Over the winter he would spend more time indoors with his family; he spent Christmas being loved by his family and they let him out like usual 2 days after Christmas.

 He returned late at night, very sick; it looked like he was choking, but there was nothing in his throat.  Lying on his side with his legs hyperextended, he was unable to get up but cried out for help from behind the trash cans.  He was found too late; the 24-hour animal hospital was a 20-minute drive and by the time we were on the way he had fallen quiet.  The symptoms were exactly the intended effects of the neurotoxic rodenticides, Bromethalin, which can be bought off the shelf at many stores.

An unregulated nerve agent that looks and tastes like cat food

Since other types of poison that are less effective have become more regulated, Bromethalin has become more popular.  It is available cheaply in forms that resemble cat food.

According to vetirenary news: 

“in animals displaying neurologic signs, specific therapy does not exist.    …despite aggressive supportive care measures, intoxicated animals usually succumb.”

in other words, by the time you see the effects of the poison it is usually too late.  It has even killed humans with very small dosages.  If you do catch the cat eating the poison, then you can save their lives by inducing vomiting – but for many outdoor cats, it is difficult to know what they eat outside, especially since rodenticides are designed with very similar shapes and flavors as cat food.

The local hardware store only sells anticoagulant rodenticide, including this poisonous fish-flavored kibble.
You can find bromethalin poison bait at many retailers and online, including this brand that ironically features a cat.

Most of the neighbors said they wouldnÔÇÖt use rat poison because they have pet dogs and cats.  We took a walk around the neighborhood to investigate any toxins out on the streets and found a bait trap with rodenticide in the alley of a nearby business. We also found a half-eaten rat in our own alley, likely one that was poisoned by the bait box. The bait box is only intended to allow small rodents to enter to consume the bait without removing it from the box, but it is relatively easy to open. The box contained blue chunks of poison on stakes. Unfortunately itÔÇÖs difficult to determine whether any poison is bromethalin or any of the anti-coagulant types of poison.  The anti-coagulant types are a little safer than the neurotoxic bromethalin; treatment is possible when the symptoms of anticoagulant poisoning are obvious.


Some stores only carry non-poison pest control, while some stores may only carry anticoagulant type due to the known danger of bromethalin;  but it can be found at the largest major retailers and online stores very cheaply and in forms that directly resemble cat food. ItÔÇÖs up to the retailers themselves to choose to carry it, though, because itÔÇÖs almost totally unregulated and can be bought cheaply without even showing ID.

Bromethalin acts like a nerve agent. The animalÔÇÖs central nervous system shuts down at a rate proportional to the dosage, so if a mouse or a rat eats a full dose, then it will die within a short time. But, if a cat ate that mouse or the same amount of poison then it would take a whole day to kill the cat. In either case, death occurs by slowly paralyzing and suffocating the animal while it is still awake. The cat wails and its tongue turns purple like itÔÇÖs choking as its brain swells. 

This is how we found our Zorro in his last moments, and who knows how many other local animals found what he did. When we canÔÇÖt save all the cats or control who leaves what on the street, we can inform people about the effects of poison the importance of responsibility and safety. Poisoning is cruel because it causes the animal great pain. Please be conscientious of what you put out on the street where stray animals or your neighborsÔÇÖ pets could find it.  The best way to control pests is to keep them out of your house and away from sources of food and water by keeping the street clean and your house sealed. Indeed, outside cats can do a great job of keeping pests away, but not for long if those pests are poisonous.

To help spread the message to our neighbors who may not always think about their quiet feline neighbors, we made a flyer to pass around our neighborhood and educate our neighbors on the dangers of poisoning and that there are alternatives for pest control. We hope that this can also help anyone else who is dedicated to making the lives of all our animal neighbors safer and more peaceful.

Comments are closed.