The Hunting Instincts of Cats
Cats are natural hunters with strong instincts to chase and kill prey such as mice and other small rodents (Purina, 2022). This behavior is hardwired into their brains and triggered by the mere sight and sound of potential prey. While not all cats are effective mousers, their desire to hunt is innate and a result of evolution (Four Paws, 2021). The hunting ability of cats depends on factors like breed, personality, and environment.
For example, breeds like the Maine Coon and Egyptian Mau are known for their superior mousing skills. In contrast, Persian and Siamese cats tend to have lower prey drives. An individual cat’s personality and early life experiences will also impact how much they are compelled to hunt. Additionally, indoor house cats typically have less opportunity to hone their hunting skills compared to outdoor and feral cats.
Why Cats Eat Mice
Cats eat mice primarily for nutritional reasons. Mice provide protein, fat, and essential vitamins that are vital components of a cat’s diet (https://www.ucl.ac.uk/culture-online/case-studies/2022/mar/do-cats-actually-eat-mice-or-do-they-just-see-them-toy). As obligate carnivores, cats must eat meat to acquire certain nutrients like taurine that can’t be sufficiently obtained from plants. Though commercial cat foods contain these nutrients, a cat’s natural instinct is still to hunt small prey like mice.
Beyond nutrition, cats are driven by their innate hunting instincts and desire to stalk, chase, kill, and consume mice and other small animals. According to experts, this killing impulse remains strong even when cats aren’t hungry (https://www.animalhumanesociety.org/resource/my-cat-just-ate-mouse-should-i-be-worried). For outdoor cats especially, hunting provides mental stimulation and satisfies their prey drive.
Indoor cats may eat mice out of boredom or for entertainment. The act of playing with live prey before killing it allows cats to practice their hunting techniques. Killing small animals like mice provides excitement, amusement, and a sense of reward for domestic cats.
What Parts of Mice Do Cats Eat?
When cats hunt and kill mice, they typically eat the meatiest parts of the mouse’s body. This includes the muscles and organs, which are rich in protein and nutrients that cats need in their diet.
According to sources, cats usually focus on the mouse’s head first as a tasty treat (1). The head contains the brain, which is soft, fatty, and easy for cats to chew and digest. After devouring the head, cats will move on to the nutrient-dense organs like the heart, liver, and kidneys.
The muscles of the mouse also provide an excellent source of protein for cats. The breast, legs, and thighs are often consumed. Some cats may also eat the tail, which contains bone, fat, and connective tissue.
However, cats tend to avoid the indigestible parts of mice, including the fur, bones, stomach, and intestines (2). These parts provide little nutritional value and are difficult for cats to break down and fully digest. The fur and bones are also a choking hazard.
In the end, well-fed house cats may not finish the entire mouse, while hungry strays are more likely to devour as much as they can. But in general, cats selectively eat the most energy-dense, nourishing morsels and leave the rest behind.
(1) https://www.untamedcatfood.com/blogs/nutrition/do-cats-eat-mice
(2) https://www.quora.com/What-parts-of-a-mouse-does-a-cat-not-eat
What Parts Do Cats Leave Behind?
Cats tend to leave certain parts of mice uneaten. This includes the fur, bones, and teeth, which cats have difficulty digesting (1). The stomach and intestines may also be left behind if they rupture during the kill, expelling the acidic contents inside. According to one source, “Cats are known to start munching the head of their prey first, crunching up the bones” (2). However, on some occasions, the heads, paws and tails of mice may be left uneaten as well.
In summary, while cats often consume mice whole, indigestible parts like fur, bones and teeth are commonly left behind after feeding. Intestines may also remain if ruptured. Depending on the individual cat and situation, other body parts like the head, paws and tail may go uneaten too.
Where Do Cats Eat Their Prey?
Cats are natural hunters with instincts to kill small prey like mice. However, domestic cats don’t always eat their catches right away. Instead, cats may carry dead or injured mice to a comfortable spot before eating them (https://www.ucl.ac.uk/culture-online/case-studies/2022/mar/do-cats-actually-eat-mice-or-do-they-just-see-them-toy).
For indoor cats, secluded areas like under beds or behind furniture are common places for them to consume prey. The privacy allows cats to eat without being disturbed. Outdoor cats have more options, often finding discreet spots in bushes, under porches, or hidden garden nooks to eat their mice.
Bringing prey to a safe place to eat is an instinctive feline behavior. It allows cats to avoid having their food stolen and enables them to relax while enjoying their meal.
What Happens to Uneaten Parts?
When cats hunt mice and other small prey, they often do not eat the entire animal. Cats tend to consume the meatier parts of their prey, like the muscles and organs, and leave behind fur, bones, and the digestive tract (stomach and intestines) [1].
There are a few things that commonly happen to the parts of mice and other prey that cats do not eat:
- Cats may leave uneaten remains as “gifts” for their owners, especially if they are outdoor/barn cats. This behavior comes from their natural instinct to bring home prey to feed their kittens and family members.
- If a cat is startled while eating (by a loud noise, a person, another animal, etc.), they may abandon the leftovers where they were dining. These scattered remains may be found around the areas cats frequent.
- For prey caught outdoors, leftover parts not consumed by the cat will naturally decay or be scavenged by other wildlife like insects, birds, foxes, and coyotes. The bones and fur do not provide much nutritional value, so they are often left behind.
Outdoors, the cycle of predation continues as scavengers consume what remains. Indoors, uneaten prey parts can present cleaning challenges for cat owners.
[1] “What parts of a mouse does a cat not eat?”, Quora, 2021
How to Clean Up After Mouse Remains
Cleaning up after a cat has hunted and eaten a mouse requires care and the proper tools. Here are some tips for safe and effective cleanup:
Use gloves, paper towels, and plastic bags to carefully dispose of any uneaten remains. Gloves protect you from potential diseases mice can carry. Paper towels soak up liquids and allow you to wrap and contain solid pieces. Seal everything in a plastic bag before throwing it away.
Thoroughly clean the area where the mouse was eaten with a pet-safe disinfectant. A bleach or enzymatic cleaner designed for pet messes helps sanitize the space and remove scents that could encourage further hunting. Focus on floors, walls, furniture and other surfaces the mouse may have touched.
Discourage further hunting by providing interactive playtime with wand toys, balls, and other stimulating activities. Hunting prey provides mental stimulation and exercise for cats. Mimicking those actions with games redirects the instinct in a positive way. Increase play sessions to curb interest in live prey.
For more tips, check out this comprehensive guide on cleaning up after a cat eats a mouse: https://www.catster.com/guides/cat-killed-a-mouse-what-to-do/
Health Risks of Mice Remains
While cats are natural hunters designed to catch and eat small prey like mice, the remains left behind can potentially pose some health hazards that cat owners should be aware of.
One of the biggest risks from mice remains is exposure to parasites and other pathogens that mice can carry. For example, toxoplasmosis is a parasitic disease that can infect both cats and humans through exposure to infected mice. According to the CDC, toxoplasmosis can cause flu-like symptoms in humans and can be especially dangerous for pregnant women as it may affect the fetus (1). Carefully disposing of any uneaten mouse parts left behind by cats is important to avoid any accidental ingestion or handling of infected remains.
Intestinal parasites like roundworms or tapeworms are other common parasites found in mice that cats can pick up if they eat infected rodents. These parasites can cause gastrointestinal illness in cats, resulting in vomiting, diarrhea, and weight loss. Keeping a close eye out for any signs of parasitic infection in cats that hunt and eat rodents is advised, and promptly bringing them to the vet if symptoms develop (2).
In addition to parasites, mice may carry other infectious diseases such as hantavirus or plague bacteria that could theoretically be transmitted to cats or humans through contact with mouse droppings, urine, or blood. While rare, any flu-like symptoms or unexplained illness in household cats that hunt mice warrants a veterinary visit to test for possible rodent-related infections.
To minimize health risks, cat owners should promptly and carefully clean up any uneaten mouse remains using gloves, double bag the waste, and wash hands thoroughly afterwards. Keeping hunting cats current on deworming and parasite prevention medication is also recommended.
Preventing Indoor Mice
There are several effective and humane ways to prevent mice from entering your home. The first step is to seal any possible entry points. Mice can squeeze through holes as small as 1/4 inch, so inspect baseboards, under sinks, and around pipes for gaps. Use steel wool, caulk, concrete, or metal kick plates to plug holes both inside and outside the home (source: https://www.corbettexterminating.com/about/our-blog/how-keep-mice-out-house-rodent-proofing-myths-facts).
It’s also important not to leave any food sources that may attract mice. Store dry goods in chew-proof containers, clean up crumbs and spills right away, and avoid leaving pet food out overnight. Using humane traps and deterrents like peppermint oil can also help keep mice away without harming them (source: https://www.thespruce.com/poison-free-rodent-proofing-methods-2656482). With some diligence in sealing up entry points and removing attractants, you can humanely prevent indoor mice.
Providing Alternatives to Hunting
A cat’s natural instincts to hunt small prey like mice can be difficult to stop entirely. However, there are ways to provide alternative outlets for your cat’s predatory behaviors.
Make sure your cat has plenty of enrichment toys that allow them to simulate hunting behaviors. Rotating different types of interactive toys will keep them engaged and entertained. Increase playtime with teaser toys like feathers or laser pointers that your cat can “catch.” Vigorous play right before bedtime can curb those nighttime urges to hunt.
For cats that go outside, consider leash walking or letting them spend time in an outdoor enclosure or catio. This allows them to be outside while under your supervision.
Use physical deterrents like screens with special tubing (https://www.catster.com/guides/how-to-stop-cat-bringing-in-mice/) to make it harder for cats to bring prey inside. Deterrent sprays made from citrus or pepper can also help.
While cats’ hunting urges are strong, providing appropriate outlets along with deterrents can satisfy their needs without the undesirable consequences.
