External pipes below ground level

[Ric2013]

@Timmy D. I always use snap traps. My understanding is mice might not necessarily go outside to die (unlike rats, which get thirsty and go outside for water). Am I right or wrong?

 

[Glasgowman]

I worked pest control for 5 years before becoming a plumber. I guarantee you that mice/rats can climb the inside of those pipe even when vertical.

Go online and buy a cheap 5m Bluetooth endoscope and some electricians fish rods. Tape endoscope to rod, stick it in pipe and have a look. Could even drill hole in wall/floor to have a look at external of the pipe under the floor.

Meant to add there is no noise at night, scratching etc

I can't see a damp proof course in the brickwork. My guess along the same lines as as Ric2013, i.e. that the pipes are drains to prevent build up of water under the building. I really wouldn't block or obstruct them. Someone put them there for a reason.

They seem to be all around the house close by and 3 bricks below the red grill vents on the wall except from that side where it’s a bit below ground level

 

[Glasgowman]

I’d bet the bellcast bead at the bottom of the render coincides with a dpc.

From the air bricks I presume that you have suspended wooden floors, the simplest thing would be to lift a section of flooring inside and have a look below- unless it’s all tiled or parquet or some such?

Yes it’s a suspended wooden floor mate. I’m due to replace the floor in next few months so suppose I could lift up and put down a section to have a look. Would you suggest blocking all holes/access points from the exterior then setting traps within the suspended floor to see if theres any actual activity on the inside?

 

[Glasgowman]

TimmyD has more experience than me as a pest controller but the way to usually get rid of an infestation of mice/rats is load the area with decent poison, wait for say 3 days or so and inspect your bait boxes and repeat until the bait no longer disappears. I'd permanently fix a metal vent/grate across that hole as they'll gnaw through a plastic one. That looks like nesting material that's been dropped at the hole/door and that trap should be placed along the wall, they usually follow the outline of buildings for safety.

I’ve heard poison isn’t the best as they can eat then die within walls etc

 

[Glasgowman]

@Timmy D. I always use snap traps. My understanding is mice might not necessarily go outside to die (unlike rats, which get thirsty and go outside for water). Am I right or wrong?

Without blocking any holes yet I’ve used a catch release trap and I’ve been catching each night but it only holds one. I got a pack of 8 snap traps tonight so there out there for tonight. Just don’t know when’s best to block outside off. Atm there’s still no sign of mice actually in the house, noises etc, only been one sighting outside and with the 4 I’ve caught so far in catch release trap.

 

[Ric2013]

Without blocking any holes yet I’ve used a catch release trap and I’ve been catching each night but it only holds one. I got a pack of 8 snap traps tonight so there out there for tonight. Just don’t know when’s best to block outside off. Atm there’s still no sign of mice actually in the house, noises etc, only been one sighting outside and with the 4 I’ve caught so far in catch release trap.

Catch release is okay, but unless you are taking them some distance away, you may find it's the same mouse every day

 

[Ben-gee]

If you lift the floor you’ll know if there’s activity by the droppings, can usually tell if they’re recent or very old (dry).
I would only “block” holes with mesh until you know what holes are for. With investigation it may prove that you can cement up the holes - but don’t do it until you know.

 

[Ric2013]

If you lift the floor you’ll know if there’s activity by the droppings, can usually tell if they’re recent or very old (dry).
I would only “block” holes with mesh until you know what holes are for. With investigation it may prove that you can cement up the holes - but don’t do it until you know.

I'd say it's almost certain mice will be finding their way into those pipes as mice are a part of our native wildlife and probably visit every garden in the land. The question is whether they are able to find anything of interest and then chew it, or whether they are merely able to enter the pipe, see it's fairly boring in there and then go back outside again.

 

[Glasgowman]

Catch release is okay, but unless you are taking them some distance away, you may find it's the same mouse every day

I’ve dropped 3 of them off 1 mile away from home. I have 8 snap traps now and caught 3 last night, so will monitor that until Saturday and get the stuff for covering each hole etc

 

[Timmy D]

@Timmy D. I always use snap traps. My understanding is mice might not necessarily go outside to die (unlike rats, which get thirsty and go outside for water). Am I right or wrong?

Spot on, move can get all of their water requirements from their food, rats can not.

If snaps work, great, because as you say, you’d rather not have dead mice in the walls (3-4 weeks of smell).