Regularly see bags of 30-40 rats from a 2 person night ratting session (using night vision scopes)
Them buggers are quite happy to carry on munching next to their fallen brethren. Nervous they are not ( farm rats mind )
As revs really. They're not easily deterred. Ignore the red light idea, they're bothered by people not lights, don't make lots of noise and don't get too close and they'll sit there happily being picked off until the food runs out. Unfortunately you'll need to be up all night for several nights to make a difference and be sure you've actually got the ones in "your" colony.
Problem is without sorting the source of food you'll not sort them long term. You'll just end up with a pile of dead rats. (and new ones feeding on them).
Council or private contractor is your best bet, I'd honestly say outdoors poison should be a last resort. It's indiscriminate (and the most effective stuff looks like coloured gains which is very appealing to birds too) and it does carry up the food chain, especially if it makes it back to the nest where the young will take it as they make lovely meals for a lot of other stuff (full grown rats less so). If you've children or pets poison should be a no go,
If you've got pets or kids then you do want rid as they are very aggressive if cornered (or that way inclined) and will scratch and bite. a rat bite has a chance of ending badly.
Traps at entry points. It can help to "Wash" the runs with something strong smelling (they don't like mint apparently so a high concentration of mint oil in water is supposed to work well, indoors I'd use bleach solution) as they navigate by scent a lot but, ultimately, if they're not causing a problem beyond "omg rats" you really can just leave them be. They do less damage than squirrels and make less mess than birds and I can't imagine you resorting to poison for those.
Someone up there mentioned weil's disease. Leptospirosis is only really a worry in wet environments such as river banks as it dies off when it dries. It will enter your system through mucus membranes as well as cuts but, so long as your garden isn't a swamp and you're not rubbing soil in your eyes you'll be fine. Unless you've pets and kids that do drink from puddles, or put hands in mouths etc. But then poison should be a no go, so use traps.
If they're in the house then get on with it ASAP, poison is usually the best method, possibly combined with traps. (traps are "best choice", and in theory you should start there but usually you'll end up with poison any how so skip the traps, just accept the inevitable smell [if you do use traps, make sure you tie them down]). Use a bromide (brimadolne) or bromidacoum based whole grain poison ideally - both acumlate in the liver so don't need your rat to have its fill in one go. With new food sources (eg bait blocks) rats and mice tend to eat a little then go back to what they know, working up to eating their fill, so often ingest insufficient poison to kill them but enough to make them wary next time, with non cumulative stuff this means it doesn't work well when there is a good source of food else where.
You'll likely need to get a pest controller to put this ^^ out for you as it should need a licence/certificate to buy it. It's available from mole country stores and similar if you've a local one and want to try your luck.
Regardless of the various "these dog" answers, animal control isn't viable, a big rat will make a mess of a dog or cat if it decides to fight & even small cuts and bites infect easily (why you don't want rats round livestock) and can prove fatal for a dog (and always expensive for you). Oh and when they don't "shake" the rat too death you'll need a strong stomach.
One thing with a dog, they're effective for flushing to guns at least.
Blasting a shotgun in barns never put off rats feeding in daylight, the noise made by someone talkng made them scarper.
Good nature traps are great but pricey.
We have a city wide predator free programme that gives away traps with the aim of killing rats and stoats to protect native wildlife: https://www.pfw.org.nz/get-involved/groups/predator-free-brooklyn/
You can make a basic DOC 200 style trap with some pallet wood arranged in a tunnel shape with two traps inside, one large one small:
Peanut butter works really well as bait if you're not catching anything move the trap to a different location. My neigbour has caught 22 rats to date!
Crush several paracetamol tableyts and mix it into peanut butter. Pop it down where you see the rats. Night night ratty.
Go round the exterior of your house with a pencil.
Fill any hole which you can fit the pencil into. You can get stainless steel wire mesh for covering air vents.
If you know anyone with Ferrets iv'e herd putting ferret shit round the garden will stop rats coming in .....
Cheers everyone and very useful.
Do I need a licence to buy the bait from Tool Station?
We had an infestation last year, middle of suburbia the buggers were out feeding in the day. I won't use bait as I have found it ineffective in the past, unless you get a specialist in, any bait you can buy requires the rats to eat high quantities and nothing else. Rat traps are the way to go, but don't bother with what are basically large mouse traps, I use rat cage traps, sometimes advertised as humane traps, they are a lot more efficient at trapping. Down side is yo need to get a bit hands on to dispatch them. A deep container of water is my weapon of choice, cleared the problem in a couple of weeks.
Rocky mountain: no, you can just buy the poison.
Lunar: that's what I did, but used an air rifle for dispatching.
A deep container of water is my weapon of choice,
And also illegal in the same way as drowning unwanted kittens. Shooting UK, plenty of other Google results (from the mail through the guardian) but this one mentions the act in question too
If you humane trap, you need to shoot them, single blow to the back of the head with a heavy object etc. You're not allowed to release either (just in case you thought it was a good idea).
Humane traps are, by and large, not a great idea.
Re the bait from toolstation, I don't think you'll need a licence for it due to the low concentration of poison. I wouldn't eat it though.
