Weasels Killing Chickens is Common, but Preventable

The Long-Tailed Weasel — Friend or Foe?

Weasels Killing Chickens is Common, but Preventable
Reading Time: 7 minutes

By Cheryl K. Smith, Oregon – Shortly after I moved to my homesteading land 15 years ago, I found a desiccated weasel in the barn. It was a long-tailed weasel (Mustela frenata), about 10 inches long from nose to tail tip, and brown in color — which indicated that it had died between spring and fall (they turn white in the winter). New to the country, I thought it looked cute and was sorry I didn’t see a live one. Little did I know weasels killing chickens is all too common.

My next encounter with a weasel occurred 10 years later and didn’t involve actually seeing one — dead or alive, but waking up to find half my chickens dead. Yup, a case of a weasel killing chickens from my coop. They had been dragged to all corners of the chicken coop — not eaten, but nearly decapitated. (Naturally, hens and not roosters.) Unable to determine where a critter could have gotten in and repair or block it, I experienced the same horror the next morning. I knew I had to do something — making weasel traps was possibly the answer.

I had designed the coop myself, believing that it was invulnerable to opossums and raccoons killing chickens as well as more obvious chicken predators. (That cute little dried-up weasel was but a distant memory.) I noticed only in hindsight that the multitude of rats that were digging under the chicken house had gradually disappeared.

The word “weasel” conjures up visions of a sneaky, devious person, or a vicious little mammal that attacks poultry just for the thrill of the kill. Think of the thieving gang of weasels portrayed in the children’s book Wind in the Willows.

Protection and Ease - Automatically

ChickSafe Automatic Pophole Door Openers with advanced microprocessor control technology give you the flexibility you need and help keep your hens safe from predators. It’s the only one available that offers both a timer and … Read more and buy now >>

Weasel words are those that are twisted or misleading, used to benefit the individual uttering them. This is believed to have come from the idea that weasels suck eggs; so weasel words are those in which the meaning is sucked out. But in fact, weasels do not have the necessary jaw muscles to suck eggs (or blood from a chicken’s neck).

When I started researching these animals, my frame of reference grew out of all of these misconceptions. I believed that my chickens had their necks chewed through because the weasel was just interested in sucking blood. My explanation for the multiple dead bodies in the corners of the chicken coop was that the weasel was on a killing spree.

These ideas are all wrong, though. As it turns out, weasels are usually more beneficial than harmful. In fact, I probably have weasels on the property right now and am not even aware of them.

Weasels in North America

The Mustelidae (weasel family) is quite large, consisting of not only weasels but minks, ferrets, martens, badgers, and otters. The subgroup Mustela (true weasels) consists of up to 16 species. The long-tailed weasel (Mustela frenata) is the most widely distributed weasel and is found in most of the United States. Other common weasels in this area are the least weasel and the short-tailed weasel or ermine.

Long-tailed weasels range from 11 to 16 inches in size, including the tail, with the males larger than the females. They are normally light brown, with a white belly and black-tipped tail. Some varieties molt their brown coat and become white in the winter. They are long-necked and short-legged creatures, a helpful adaption for getting into small places. Their voice is said to be a high-pitched shriek.

Reproduction and Lifestyle

Long-tailed weasels have only one litter each spring, regardless of food supply — unlike least and short-tailed weasels, which can have a second litter in late summer. The actual gestation period is from 205 to 337 days; however, the mating occurs in the spring and then the ball of cells called a blastocyst floats feely in the uterus for nine to 10 months before implanting and developing into a kit.

Three to 10 babies are in each litter; the babies are called kits. Once kits are born and the mother starts lactating, she does not go into heat for another 65 to 104 days. She can also protect herself and her kits from interested males by choosing or making a den with entrances too small for them to enter.

Kits are born with fine white hair covering their bodies. They get their razor-sharp milk teeth in three or four weeks but do not open their eyes for another week or so. They can start eating meat after about a month — in their blind condition — but may not be weaned until they are up to three months old. They finally reach full size at six months of age but are sexually mature several months before then.

Weasels are mostly nocturnal and solitary, living in dens that are constructed under rocks or logs in a hole, usually near a water source. The den is dry and padded with leaves and even fur from some of their prey. Weasels are also known to move into the previously used den of another ground dweller such as a prairie dog, rabbit or gopher.

Their range is normally 30–40 acres. They spend most of their time on the ground, but also sometimes climb trees.

Males live separate from the females and kits. This leaves the burden of feeding the kits entirely to the female. According to biologists, males will occasionally bring a dead mammal to the female’s den, but such generosity is linked to their desire for sexual activity rather than feeding the young.

Weasels on the Farm

Weasels are actually more beneficial than detrimental on the farm — most of the time. They eat rodents, fish, birds, and frogs, as well as eggs. They are excellent helpers around the chicken house, as long as the rodent population is thriving because they normally prey on a species that is regularly available. Only when they are running out of food — especially when they have young to feed — do they turn to chickens as a food source.

Because weasels eat other small animals such as mice, shrews, voles and rabbits, they can also help protect the vegetable garden. The lanky-bodied weasel even has the ability to pursue these critters down into their burrows.

Weasels also provide food for foxes, coyotes, hawks and owls. So their presence may help the chickens in another way — redirecting the predators to another food source.

Understanding Why Weasels Killing Chickens Happens in Sprees

When prey is in short supply, weasels will often kill more than they and their kits can immediately eat. The females with kits need to ensure that they will survive, so they take what they can get. This is how the idea that they are thrill-killers arose.

Their killing instinct is also triggered by movement — which is why “freezing” by small rodents may protect them. In a chicken coop, the weasel is unable to stop itself from killing.

First, the wild, squawking and flapping movement of the chickens triggers the instinct, causing the weasel killing chickens to go on killing until it perceives there is nothing left to kill. Second, it will want to kill as many prey as possible, with plans to save the extras for future meals. This is why my chickens were dragged down behind the feed cans into corners. The weasel was trying to hide them, most likely with plans to return later.

The method that weasels use to kill their prey is to bite the back of the neck of the animal. The long teeth penetrate the neck with only two bites. This signature method of killing led to the myth of blood-sucking.


Preventing Weasels in the Chicken Coop

Despite their helpful attributes, it is wise to try to prevent weasels from ever getting inside a chicken coop. The best time to do this is when you are constructing it. Do not build the coop directly on the ground; put a floor in it or make sure it is raised up in some way. This was my mistake. I paid attention to trying to prevent holes in the top and sides, while the rats were digging holes underneath. When that food ran out, a weasel used those very holes as a way to get in and get chickens.

Another essential to keeping weasels out of the chicken coop and other buildings is to make sure that there are no openings larger than one inch — or even less if you want to be extra sure. (The common saying is that weasels can get in through a hole the size of a quarter, which is 7/8-inch across.) The best method is to use 1/2-inch hardware cloth or a similar material in areas where you want ventilation. Make sure the coop is completely enclosed.

As time goes by, rodents will start to gnaw holes in the wood. Be aware of these and repair them quickly. Pieces of metal, even flattened tin cans work well to cover such hole.

If a weasel has already caused chicken losses, consider a live trap. Havahart has an extra small live trap that will work for weasels, for only about $24. Make sure it is set so as not to harm other animals. Although the damage is done by the time you determine a weasel is killing chickens, you can still try to trap it to prevent future losses. You will need to live somewhere that you can release it far from its range so as not to create a nuisance for others.

Because weasels are fur-bearing animals, check with your state Fish and Wildlife Department regulations before trapping with a trap that kills weasels.

Like in most affairs, the best advice is to be proactive. Make sure your coop is secure and be aware of the rise and fall of various wildlife populations, such as rabbits and rats.

What are strategies for preventing a weasel killing chickens on your farm or in your backyard?

Names for a group of weasels: Boogle, Gang, Pack, Confusion

Cheryl K. Smith raises chickens and Oberian dairy goats in the coast range of Oregon. She is a freelance writer and the author of Goat Health Care and Raising Goats for Dummies.

Originally published in the September/October 2014 issue of Countryside & Small Stock Journal and regularly vetted for accuracy.

19 thoughts on “Weasels Killing Chickens is Common, but Preventable”
  1. I lost all my girls this spring to a fisher- a kind of weasel very prevalent in my area of Massachusetts. It killed the chorderedickens across the street and in our neighborhood- which are very large acreages and farms. I have ordered the Cadillac of coops to be delivered and built on site from a company in Texas. It will have an automatic door and a solar water heater. I can’t bear to lose my girls again 🙁

  2. I lost a chicken Wednesday and blamed myself for letting them free range while I left to go shopping. So I locked them up in their coop, and lost another this morning. Apparently I never considered weasels. I built the coop strong enough to keep cats, dogs, and hawks away but didn’t considering a weasel. I kinda forgot they existed.
    So now I’m going to replace all the chicken wire with hardware cloth.

  3. I lost 3 hens ( my girls) last night. So sad. everything seemed to be buttoned up, but I suspect a weasel due to the fact that nothing was eaten. Other girls are on high alert now. They must have been terrorized watching this happen. I won’t sleep til I check and find the hole that it got in at. So sad. Any recommendations welcomed.

    1. I had 3 of my chickens killed inside of my coop. Went in during the day heard a noise, looked up inside near ceiling and noticed a brown weasel. Checked for holes and spaces it might have gotten in. Then nothing happened for 4 days. I just went in my coop this afternoon and 7 of my hens were dead inside of my coop, so sad I lost my girls, but one of them was unhurt. I did try to catch it but no luck. Not sure how to get rid of this weasel. I could really need some help to get this thing out.

      1. Donna,

        Sorry to hear about your loss. Weasles are indeed weasley. They can squeeze through very small spaces and they like to dig. Check around all the edges to see if there are small holes. You can bury 1/4-inch hardwire under the bottom edge of the coop to limit digging. Also check for small holes under the coop eaves, and around the edges of doors. Add hardwire anywhere you see small gaps. You can try live trapping the weasel and then calling your local branch of fish and game, or a local pest control company.

  4. A good way to find holes in your enclosures or buildings is 2 turn on the light and at night walk around your building and you’ll see where the light shines out the holes in your building.

  5. I lost my little flock last week, during the daytime, in their pen! Such a terrible thing to come home to a quiet yard, and to go look your girls and they’re all dead. I had pen of hardware cloth, but dirt floor, and same as the author, rats started to tunnel in. I wasn’t concerned with them and never new we had weasels! I bought a cheap hunting camera and got many pictures as he came back multiple times (day and night). Hunter friends tell me it’s a Mink. I tried to avenge my girls, but now that I have traps hasn’t been back. Sad. Get yourself a cheap hunting camera (trail camera) and see what’s going on before it’s too late

  6. Here in japan I’ve got a number of weasels trying to get at my flock on a regular basis. When building my coop I buried the mesh a foot under the ground all along the outer coop edge.
    These weeks still dig tunnels all over the place and can dig a dozen feet without a problem so I’ve had to be proactive.
    I got a couple of traps. The old steel snap traps the hunters used to use for mink and martin. The first trap I set was near a spot I saw one the day before. I baited it in the middle with some bacon fat. The next day I had a weasel get his front paw snapped in it. I heard a loud chirping sound and didn’t know what it was. When I went to checkvthe trap the little bastard went bezerk and tried to spray me like a skunk with a foul smelling spray. I retreated to get a long handled spade and finish it off.
    The very next day I encountered another weasel in the same spot even bigger then The first.
    But it knows the trap is dangerous and doesnt take the bait.
    I built a trap box out of wood. It’s basically a long slender box with one entrance. The steel trap can be placed inside the box so that the weasel must step on the trap in order to make it to the back of the box to get the bait (usually meat or innards of something).
    My neighbors are always telling me about their sightings of weasels since they know I’m in a lifelong battle of wits with these little buggers.
    I have yet to lose any of my ladies to one of these pests but it’s because I’m proactive.
    Eventually I expect to have losses, which will be horrible since my flock of auracanas (blue egg layers) and silkies were all incubated and raised with care by my wife and I.
    Be proactive if you can. Think of how they will get at your girls and try and prevent it if possible. If you need to trap them, do it, and don’t feel bad about it. We have an infestation of them so I don’t care to try and relocate them. They have abundant frogs in the nearby rice Paddy’s to support a big population.
    Good luck in your struggle.

  7. A few years ago I lost 17 hens. I rebuilt the coop. Today the security camera caught a weasel running across our front yard around 6pm. Still plenty of light. I better check every crack.

  8. I am having a drink to calm down as over the last few nights I lost a lady one after the other. I spent hours and hour and hours shoring up the coop. The weasel kept getting in. I bought a bunch of traps and poison and nothing. Earlier today I bought a baby monitor to so that if something was happening I’d hear it. Well 30 minutes ago I did. What a horrible raucous. I ran out in my birthday suit(I was in bed sleeping) hit the floodlight I set up and there it was running around in my coop. I did battle like the a madman with that bastard using the small shovel I had set up to whack him with. I got him and am very happy with myself. A little shook up but happy.

    So if you are close enough to your coop get yourself a baby monitor. I wish I had after the first of my girls went down.

  9. It is not legal in most states to relocate a live trapped animal. Do not advocate this practice. Dumping a problem predatory animal possibly carrying disease to another property/site is absolutely poor advice. Check with your local wildlife associations. Most advocate killing the problem predator by state law. Not dumping it upon unsuspecting neighbors.

  10. I lost 2 girls from one of my coops, and I bought these square things with blinking eyes from Amazon. Well, they worked. The weasel didn’t come back. If anyone wants to know what they are, I can find the brand.

    1. Hello! I am having a terrible issue with Weasles and my chicken..I have lost probably 20 chickens..Can you tell me the name of these blinking lights?

      1. My daughter and her kids have lost 3 now. And they only have about a dozen. Did you get a reply on the blinking eye

    2. I would like to know about the blinking lights! I have been raising chickens for about 13 years and
      now there being killed by those little suckers

  11. Just lost my whole flock to a weasel. I am devastated my poor girls. They were so sweet. Even my little Banty Rooster. I had him for seven years. Fourteen in all. Two nights, I feel so guilty. They had a wonderful house attached to my barn. A couple small holes that we thought we had blocked . The weasel just bit them on the back of the neck and sucked their blood. So brutal. I like to think nature has its reason but he didn’t even eat them! This is the worst loss ever. I have had chickens for over 30 years. I am heartbroken .

    1. Susan,

      So very sorry for your loss. I know it’s hard to feel like you haven’t done enough to protect them. The editorial staff feels for you.

Leave a Reply

Your email address will not be published. Required fields are marked *