Mouse nesting locations in the Prius Prime

I currently have a large (rat size) glue trap (six of them) in my garage. Checking it daily but have not caught any in the last 5 days. I had two set up before, and caught 5 in one trap in a few days, another one was empty but had signs that some other larger animal has got stuck and escaped. I ordered a 5 gal bucket mice trap reviewed as the world's best mouse trap. Haven't got it yet, but when it comes in I will see how effective it is.

 

Here is another photo showing where the nest was located. It is directly under the inverter assembly, but still not exactly sure what part it is on. I don't think there is any damage to the wire or anything else, so I am not going to disassemble anything. But without removing the inverter unit, I really can't clean and sanitize the site the nest material was placed. Also, it is at the location where physically blocking the entry is almost impossible without first disassembling the inverter. The smell and remnants of previous nesting material may attract the new mice to come back to the same location.

 

I haven't tried it yet, but the predator scent has not shown to be effective in deterring mice. In general, no smell-based repellents have been shown to be effective.

Yeah, it is probably the most inhumane way of trapping and killing mice. Also, it is not advised by many due to possible contact with infectious materials (droppings and urine). And, it is rather expensive since it can not be reused. I am hopeful that the bucket trap will work better.

 

Yes, eventually, the hope is to clean up the garage and rodent-proof it by closing all potential entry points and finally liberating it to use it for CARS. But, before we can do that, we have to first construct a "real" barn in the backyard to move our "mini-farm" equipment and stuff. Once in a secured garage, it will have much less chance to have mouse invasion into a car, I think. But this is such a huge project, I am not likely to finish it anytime soon.

In a meantime, cars have to be parked outside, and I have to come up with a way to protect them from curious mouse explorers. If I continue to see occasional mouse visitors into the engine bay, then I may have to try the BoxKat Rodent & Mouse Barriers I mentioned in my comment #1.

Yeah, they are vermins, but they are highly adaptable and smart animals. Collectively about 40% of all mammal species are rodents. And mice collectively account for most of the species in the Order Rodentia. They did not become the most populous and thus successful mammals in the world by chance alone.

 

For small rodents, population dynamics is a well-known phenomenon. Lemings and voles are both known to show cyclical population fluctuation. Other small rodents also show less regular population fluctuation. I am sure that the predator population would play a role in this. It is possible that after years of TNR efforts, our feral cat population has started to decline. That may have caused the increase in the mice population around our home and mouse infestation in our vehicle for the first time in my life.

Also, it is quite possible that the increased mouse population may be caused by some other anthropogenic ecological imbalances, such as climate change, deforestation, and developments leading to the loss of larger predators.

 

Here is a list of references I have found on the Peromyscus maniculatus repellent so far.

Only effective in eating (not volatile form)
anthraquinone Repellent application strategy for wild rodents and cottontail rabbits - ScienceDirect

D-Pulegone
https://link.springer.com/article/10.1007/BF01245967

elaiosomes of Corydalis aurea (Fumariaceae)
https://bsapubs.onlinelibrary.wiley.com/doi/abs/10.1002/j.1537-2197.1985.tb08442.x

Ortho-aminoacetophenone
https://onlinelibrary.wiley.com/doi/abs/10.1002/(SICI)1096-9063(199601)46:1%3C55::AID-PS313%3E3.0.CO;2-%23

Mestranol
https://digitalcommons.unl.edu/vpc6/29/?a_aid=3598aabf

thiram (0.31, 1.25%), methiocarb (0.031, 0.5%)
https://digitalcommons.unl.edu/ewdcc2/29/

Siberian pine needle oil
https://www.jstor.org/stable/3802433

endrin (no longer produced pesticide with environmental harm)
https://en.wikipedia.org/wiki/Endrin#:~:text=In%20the%20environment%20endrin%20exists,the%20compound%2C%20or%20skin%20contact.

alpha-naphthylthiourea (ANTU)
Alpha-naphthylthiourea as a conditioning repellent for protecting conifer seed

May show some repellent properties
CHF, manufactured by Coolworks BV, is a pelleted, composted
1:1 mixture of mink/fox manure and peat.
https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1032&context=birdstrike2008

Orthoaminoaceto-phenone (avian repellent)
https://link.springer.com/article/10.1007/BF00994315


Not effective
MAMMALIAN PHEROMONES
https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1443&context=wdmconference

predator odors
https://link.springer.com/article/10.1007/BF01022552

predator scent
https://underc.nd.edu/assets/174555/fullsize/nickels_underc_west_2013.pdf

weasel odors
https://link.springer.com/article/10.1007/BF02059606

R55 and many other compounds tested
https://books.google.com/books?hl=en&lr=&id=JUtaDwAAQBAJ&oi=fnd&pg=PT421&dq=Peromyscus+maniculatus+repellent&ots=ydBIAy1Dh1&sig=hApzcxCMwSZDZ8JOJOeeBsIxad0#v=onepage&q=Peromyscus%20maniculatus%20repellent&f=false

ultrasonic rodent repellent devices
Efficacy test protocols for evaluation of ultrasonic rodent repellent devices

 

OK, it has been 20 days since my first discovery of the mouse nesting under the hood. Today, I am still seeing evidence of mouse activity (droppings) in the engine bay. It rained all day yesterday, so I kept the hood closed all day and all night for a full day and a half. Now I see the return of a mouse (or mice), despite the fact that the mouse traps were set, all repellents so far tried are still being used.



As a report of the 5 gal mouse trap I purchased from Amazon, it turned out what I bought is a cheap Chinese fake, not the original design made in the USA by Rinne. Not surprisingly, the cheap fake trap has not caught a single mouse as of today after 5 full days. I ordered the authentic Rinne trap, and now waiting for it to be delivered. Here is the video showing the difference between the authentic one and the fake.
The World's Best Mouse Trap Vs. A Copycat From China... - YouTub

 

I got mine yesterday. I am going to set up cheap Chinese fake one and made in the USA by Rinne authentic one side-by-side in our chicken coop where I know there are enough mice roaming around all year round.

 

It's very hard to know what the population dynamic of rodents on our property is. There is no study done on the subject in our immediate region. I have always seen some rodent activities in the woods and chicken coop which is further away from our home and garage, but that is their native habitat. I am pretty sure that the infestation problem has spread to our garage (aka barn) and maybe to our house recently in the last year or two.

But I am not catching any more mice in the garage with traps after 5 mice were caught in the first 2 to 3 days. I really don't think they are all gone. Maybe they adapt very quickly to traps, and now the remaining mice are totally avoiding the traps.

In any case, I saw a sign of mouse activity (dropping) again this morning in the engine bay of my PP. I think I will have to move to the next phase. Repellent did not work, traps did not work, and now the last thing I have not tried yet is using the rodent barrier fence. I am going to order this. https://www.miceout.com/pages/why-boxkat

 

I set up cheap Chinese fake one and made in the USA by Rinne authentic one side-by-side in storage shed where I have seen signs of heavy mice infestation.



Just overnight. I caught 1 mouse in the authentic Rinne trap. None in the Chinese copycat trap.


Catch and release, I took the mouse way back into the woods where it belongs.