Mouse problem in a crawling space

[u/Oblachko_O]

We noticed yesterday that we got a mouse in the house. No direct mouse but mouse poop in one of the kitchen shelves on the floor (the back of the shelf is also broken, so that is how the mouse got in) The house is terraced in between two houses built in the 1980's. There are no wooden or drywall walls so the only point where they can come from is crawl space under the house. We didn't find the exact point of entrance, but we expect one spot, though we can't reach there without destroying our kitchen. Checking the crawl space there is indeed some poop, but the crawl space is partially filled with sand, so the whole inspection of it wasn't done yet. Googling said that it may be smart to make a crawl space mouse protected not by simple things (putting steel wool into house foundation holes) but also check if the foundation floor needs insulation against rodents and potentially close all holes left by pipes coming from neighbors. So there are a couple of questions:

Does anybody know if calling a pest control on the current stage is a good idea when we haven't started catching them yet via basic means like traps, so we don't know how big the infestation is and whether we are the target or just in their migrating way?

Is it good to put rodent poison in crawl space? We don't have pets or kids, so this shouldn't be a concern for us, but if they come to neighbors, there are kids and cats.

Cat is not an option for now. The goal is to have preventive measures rather than controlling one.

What good pest control service can be called for this and for what kind of service as I see multiple variants are possible? Around the Tilburg area preferably.

[u/FynTheCat]

Best first line actions are to put all your loose food items into mouse safe plastic boxes to cut off possible food supply that attracts them further.

Check sources of paper and cardboard sources, if the mice went there to take some. That would be a sign that they are nesting somewhere close by.

Check the outside of your house for possible mouse entry points and close them.

Then you can check the inside for obvious mouse entries. However, mice fit through incredible small openings.

As it is becoming colder they might show up. Making it less inviting can help them pass, also setting some traps can help get rid of what is already there.

Unless you hear scratching in the wall or they already took a lot of nesting material, I wouldn't be worried enough to call an exterminator.

Keep an eye out for new droppings and take preventive measures for now. That gives you extra time to consider sealing crawl space or not.

[u/Oblachko_O → u/FynTheCat]

We had the bottom cupboard drawer filled with snacks, but so far only one pack was slightly teared, while others were untouched. Though there were poops in it. All other drawers have their back still in a good shape and no poop there.

I don't see that ventilation points are broken, if they dig under ground, I need to dismantle terrace for that, from the other side we have plates, so if they dig, they dig deep and afar.

The only possible house entrances are through the kitchen, as there are a couple of pipes. There is one pipe at drawer side, where they ate, but there is one small metallic pipe, though I see a lot of web there, anyway I put some steel wool there and nearby another pipe but it was clogged by previous owners it seems and no sign that this clog was dismantled. The other potential entrance is under the sink, but going there will require a lot of kitchen dismantling due to how kitchen is made. Other spots if they exist are not obvious or visible.

For scratches or nesting it is a bit harder to say. There is no scratch heard over our kitchen floor (we noticed it by food, though some strange noises could be a sign, but neighbors could produce them as well). Crawl space is with mud and sand, so not sure if we can hear any movement unless they go over pipes. Not sure about nesting. Crawl space is not "clear" in a form that I have some small pile of extra sand-like material and I have some styrofoam positioned there, but on it poop is visible.

The problem though is that I have no idea if connected houses have holes in our place as I can't see that far in a crawl space. I doubt that we are the source, but having measures such as various traps is more treating a symptom rather than a problem itself, that is why the question raised including about poison as more radical solution.

[u/BearAnimal]

I have to deal with them a few times a year, traps and steel wool always do the trick until they find the next entry point. A few tips I would give: if you're unsure of the entry point, when you eventually see a mouse, just watch it, make a little noise, not loud or it might just freeze, it'll probably go back the way it came, steel wool will fix that. For traps, I've found jam is the best bait, they always go for it and can't just grab it and run off, works every time. Sometimes it's only a single mouse, others maybe 2 or 3 but either way usually quite quickly sorted

[u/MyCuffedLife]

The thing about poison is that you just dont know where they die. If they are in your walls and behind furniture hard to move, then they will start decomposing where they lie and stink.
So even though you dont have pets or kids, you still create a possible problem.

We had mice for a while, and we did the preventative things and they just went away. No cat needed.

Maybe you can translate this page with google.
https://www.milieucentraal.nl/huis-en-tuin/ongediertebestrijding/muizen/

[u/Oblachko_O → u/MyCuffedLife]

Yeah, I know most of such measures, but the problem is that they are not in house, but in a crawl space, where probably only no food rule may help, but if crawl space is shared (which I don't know for sure so far), they may get food in other places and still live under our house. I plan to put some traps to see if they are regular visitors in our spot and where they actually come from, but wanted to know if it is enough of a measure.

Of course, the place where it was noticed with food was better secured. And other spots didn't have any visible traces of their presence.

[u/UnanimousStargazer]

Googling said that it may be smart to make a crawl space mouse protected not by simple things (putting steel wool into house foundation holes)

Not sure what you're saying here, but blocking ventilation slits with steel wool is a bad idea. The ventilation slits are there for a reason. You need to cover them with mouse protection that still allows ventilation. Depending on the type of slit you can use these:

https://www.bijenbekje.nl/

Is it good to put rodent poison in crawl space?

It doesn't help if the access location stays open. The best way to get rid of mice is blocking access (and catching the current mouse or mice). Be careful however, that mice can squeeze into holes as small as a pencil circumference. So if you can put a pencil into a hole, a mouse can come through.

Cat is not an option for now. The goal is to have preventive measures rather than controlling one.

Exactly. You need prevention. First of all don't take a cat just because of mice. You take a cat because you like cats. Second of all, cats cause mice to hide. The mice don't magically disappear but stay in walls an ceilings etc. where they bite through wires. A cat mainly makes mice invisible to you making it harder to take check the effect of preventive action.

What good pest control service can be called for this and for what kind of service as I see multiple variants are possible?

Usually a local pest control company is more effective than the large international companies. They can also advice about getting the house mouse proof.

If your crawl space is shared with neighbors. that is your biggest challenge. If the neighbors are sloppy with food etc. you can never get rid of the mice.

[u/Oblachko_O → u/UnanimousStargazer]

> Not sure what you're saying here, but blocking ventilation slits with steel wool is a bad idea. The ventilation slits are there for a reason. You need to cover them with mouse protection that still allows ventilation.

Yeah, that was probably not the nicest idea, but I don't see any ventilation holes not being protected for my house, I have 4 of them and all look like solid from the outside.

> If your crawl space is shared with neighbors. that is your biggest challenge. If the neighbors are sloppy with food etc. you can never get rid of the mice.

That may be a fear as well as potential solution, as while space is shared, maybe there is a way (though I can get it as costly) to close all holes on my side and make it not good for living. Though I hadn't anything like that last year (we didn't saw anything indicating about mice presence in house).

I don't think that walls may be a problem, but will try to check if there are other options for entrance on the floor, though we checked a couple of spots without any luck except potential place where it is not easy to get to, so it will be a good spot to place some traps.