last updated 2 Feb 2024
Background:
In the fall of 2024 I had rat problems (Killed 7) in Davis and mice at our cabin at Tahoe.
We were getting about 1 a week in traps even after putting bait cubes (poison out).
We didn't want to continue to use traps because the cabin was vacant weeks at a time and 1 trap I forgot got a mouse that started to smell.
There was a myth that the bait would smell-taste better than food an they would eat it and go outside or back to their nest and die. Not true.
Steps:
A successful and effective rodent control strategy typically involves
- Sanitation measures
- Rodent proofing (exclusion)
- Population reduction (trapping).
Solutions:
See How do you get rid of mice when the mouse traps aren't working? | Quora
See Rodent Control Products | Twin Home Experts
The 7 Best Mouse Traps of 2024 | the spruce>
Terminix mouse control resources
Traps:
Old Fashioned
VICTOR Easy Set Mouse Trap
Same as original but with,
Expanded trigger for easy setting
Trigger pedal has a "cheese scent" that will attract foraging mice. However, you can add a small smear of peanut butter if you want to make certain you catch the rodent.
The plastic bait peddle in new model is a little harder to set than the old metal catch.
Childproof tunneled traps
Tunneled traps work by forcing the Rats to only go in for the bait head first, this will prevent the Rats from stealing the bait from the top, sides, and back. They also allow you to release the body in the garbage without touching the mouse.
Kat Sense Covered Rat & Chipmunk Traps, Prevents Accidental Triggering with Tunneled Design
https://www.amazon.com/Kat-Sense-Prevents-Accidental-Triggering
UCatch Rat Trap - tunneled
A friend has these and likes them.
Electric:
Electric traps get good reviews.
- 100% Kill Rate - Beveled columns also help to keep the mouse in place over the trigger plate to prevent escapes
- Humane, High-Voltage Shock - Once inside, the circuit triggers a high-voltage shock, humanely killing the mouse in seconds
- Built-in Safety Features - A safety switch automatically deactivates the trap when opened, helping to protect children and pets
- No Touch, No See - The removable kill chamber allows you to easily discard dead rodents without ever having to touch or view it
- LED Alerts – A green LED light notifies you of a catch, so you know when it’s time to empty the trap without having to check manually
Victor gets the best reviews:
Victor M250S Indoor Electronic Humane (kills mouse instantly) Mouse Trap $20
Victor M1 Smart-Kill Wi-Fi Electronic Mouse Trap $49
Will send a notice to your phone when a mouse is killed.
Repellants:
Fresh Cab Rodent Repellent
Active Ingredient: Balsam Fir oil , - Child, pet safe
Mouse repellant packets to be used in enclosed spaces indoors, pantries, closets, ...
Smells good to people.
Grandpa Gus's mouse repellant pouches
Essential oils: peppermint oil and cinnamon oil.
TomCat rodent repellant spray
Inside and outside, Peppermint oil 0.5%, Cinnamon oil 0.25%, Sodium Lauryl Sulphate (SLS) 1.5%
SLS is what’s known as a "surfactant." It lowers the surface tension between ingredients.
Some are outdoor only, so read the label.
Purcor Pest Solutions
Essential oils that may be helpful in repelling rats and mice include peppermint oil, lemon oil, citronella oil, and eucalyptus oil. You can make an essential oil spray by mixing 2 teaspoons of oil with 1 cup of water or rubbing alcohol in a spray bottle.
Repellants should be replaced every 30 days.
TomCat Rodent Preventer granules - Outdoor
Peppermint oil 2%, Cinnamon oil 1%, Sodium Lauryl Sulphate .95%
TomCat Rodent Repeller plugin diffuser
ouroilyhouse.com/mouse-repellent/
- 4 oz Glass spray bottle
- 15 drops of peppermint essential oil
- Equal parts unscented witch hazel & water
Victor Catch & Hold Small Multiple Catch Animal Trap (up to 4 mice) - Catch and release in your enemies yard.
Ultrasonic sound repellants. They are of questionable effectiveness. See ultrasonic Pest Repellers
Poisons don't address the underlying issue: They only kill the mice you see, not the ones hiding or the ones that will come in later. Sealing entry points and addressing attractants like food and water are more effective long-term solutions.
There are several types of poisons, anticoagulants, and several other types that work in diffent ways.
Some common rodenti TARGET="_blank">
Brand | Rodenticide | type | Chemical Class | Days |
Dehyd- ration | Amz |
Mouse Out | Warfarin * | Anticoagulant | Hydroxycoumarin | Multiple | |
TomCat: | Bromethalin | Non-ancicoagulant | Neurotoxin | Single day | | 4.6 (8) |
d-CON: | Cholecalciferol | Non-ancicoagulant | Vitamin D3 - Liver failure | multiple days | Y | 4.3 (13K) |
* AS I Recall Dad took Warfarin for his heart issues.
Days of feeding needed.
There are 6 Anticoagulants, and 4 Non-anticoagulant on the market. Then Non-anticoagulant work in different ways.
Dehydration - d-Con DOES NOT advertise that dehydration will make mice go outside in search of water. The features they advertise are:
1. Typically, rodents begin to die about three days after feeding on the bait. Nice to know: Because mice don’t die on the spot after eating the bait, you won’t have to deal with disposing of the dead pests.
2. They don't have anti-coagulants or neurotoxins, so they are less dangerous if your pet of child eats them.
Poison does NOT cause the rodent to go out to drink, and thus die outside. See Does Poison Make Rats Thirsty And Die Outside? | Salt Lake City Wildlife
-
Anticoagulants:
Our livers make a special enzyme that allows our bodies to recycle Vitamin K. Our bodies need Vitamin K to make the blood clotting agents that protect us from bleeding too much. Anticoagulants stop this enzyme from doing its job. Our bodies store an extra supply, but if we are exposed to enough anticoagulant, the supply will run out and internal bleeding may begin.
In 2020 the California Department of Pesticide Regulation (DPR) banned Second-Generation Anticoagulant Rodenticides (SGARs) due to their threat to mountain lions and other wildlife.
- Bromethalin (TomCat) First registered by the U.S. Environmental Protection Agency (EPA) in 1984.4 It stops the cells in the central nervous system from producing energy. The nerve cells swell, this puts pressure on the brain, and paralysis and death soon follow
Bromethalin ingestion causes muscle tremors, seizures, heightened sensitivity to light or noise, and hyperexcitability if the animal eats more than a lethal dose. The onset of signs depends on the dose. If a lethal dose is eaten, signs may develop 8 to 12 hours or several days after ingestion and progress over a period of a week or longer. In this case, animals lose their ability to control their hind legs or sense where their hind legs are. Animals may also vomit, lose interest in food, or adopt strange postures.
- Cholecalciferol (dCon) - First registered as a rodenticide in the United States in 1984.4 Cholecalciferol is vitamin D3.13 Vitamin D helps the body maintain calcium balance by enhancing absorption of calcium from the gut and kidneys.13 Toxic doses of cholecalciferol lead to too much calcium in the blood, which can affect the central nervous system, muscles, the gastrointestinal tract, cardiovascular system, and the kidneys.13 The body's ability to maintain proper calcium levels must be overwhelmed before cholecalciferol becomes toxic. Rodents must eat several doses of this rodenticide.
Signs in animals include weakness, depression, and loss of appetite. Signs progress to include vomiting, increased thirst, more frequent urination, dehydration, and constipation.13 Vomiting, diarrhea, loss of appetite, and depression may develop within 12 to 36 hours after exposure and the kidneys may fail within one or two days.
Several places recommend against poisons indoors because mice may die in a wall or other unreachable place in the house causing smell.
Source: National Pesticide information center
How d-Con Mouse Baits Work
The active ingredient in d-Con bait blocks is Cholecalciferol which uses NO anti-coagulants or neurotoxins.
After mice eat the bait, they don’t die on the spot; they return to their nest.
Tip: Check d-Con bait station’s clear window. If the bait hasn’t been gnawed, move the device to a new location.
Typically, rodents begin to die about three days after feeding on the bait. Signs of infestation should disappear then, too.
Nice to know: Because mice don’t die on the spot after eating the bait, you won’t have to deal with disposing of the dead pests.
How to Kill Mice and Rats Using Tomcat® Disposable Bait Stations
General Guidelines
Rodent Control Products | Twin Home Experts
FASTEST Way To Get Rid Of A Lot Of Rats! | Twin
Most People And Even Pest Controllers Make These Huge Mistakes When Trying To Get Rid Of A Lot Of Rats:
- Immediately set a bunch of traps
- Set up poison bait boxes on the perimeter of the home.
- DO NOT perform a proper in-depth inspection of the affected structure.
- Never pinpoint the rat’s entry point into the home or structure.
- Never identify species of the rats ( roof rat or Norway rat).
Just because your local pest control companies have great reviews, don’t expect to get rid of your rat problem fast, don’t pay anyone in full. Make sure you find and seal up your entry points, then set up effective rat traps like the Twin Traps.
Smell:
The decomposition of the carcass depends on the weather. A dead mouse will start letting off a powerful smell in one or two days in the summer. In the winter, the scent can take up to a week to become evident. But it lingers for longer because the body decomposes much slower in cold weather.
How To Identify & Get Rid Of A Dead Mouse Smell
Pest control Companies - Exterminators:
I called several.
- One in Woodland said they'd hire a contractor to go find and fill any openings in house, then put bate cubes around.
- Western Exterminators which services North Tahoe said they'd come out and look for openings into you house or openings into places like a pantry and close theml
- Critter Bros - CA and NV.- (916) 257-8739
- Others
- Sierra Wildlife Control (916) 367-0718
- Twin Home Experts CA, SC , AZ, & UT - (877)713-6895
I asked them if they had any way of setting off a smoke bomb under the house and looking for holes without having to crawl under the deck and they said no.
Smoke Testing:
Smoking THEM OUT!! Best way to find and remove rats...Best rodent REMOVAL | Twin Home Experts| YouTube
COMPLETE RODENT CONTROL - SMOKE TESTING EXPLAINED. Truly Nolen | YouTube
John McNerney Wildelife Resource Specalist - City of Davis
Attachments
Mon, Jan 8, 3:22 PM (6 days ago)
Hi Don-
Thanks for reaching out about your rat challenges. Sounds like you are on the right path to resolving the issue. Rodenticides can be helpful to control large numbers of rats outside, but you should avoid using them indoors. Rats that eat poisons indoors will end up dying in the walls, attic or crawl space…causing a terrible smell.
I suggest that you keep trapping in the kitchen as that seems to be where they are coming. You could try to place a trap up in the attic (on a board above the insulation) to see if you get any there.
Most importantly, I would spend some time looking for points on entry into the house and sealing those up. This involves searching the outside perimeter of the house from top to bottom looking for any gaps or holes that are larger than a nickel. Fill those gaps with steel wool or spray insulation foam. Check under exterior doors also and install or replace sweeps under the doors with gaps.
Finally, consider cutting back dense vegetation around the exterior of the home. This could aid in entrance hole detection and reduce cover for rats around the home. Keeping tree limbs and vines off the roof is also important in preventing rats from accessing the roof/ attic.
If you would like more information, take a look a the UC Agricultural and Natural Resources Extension IPM program webpage. Rats - National Pesticide Information Center - Integrated Pest Management Program - University of California Agriculture and Natural Resources
Rodenticides | National Pesticide Information Center - Oregon State
I hope this is helpful,
John
Links: