Your tunnel-box setups are well constucted and with obvious research and experience behind it.
Good luck with your revised proposals for setups.
Ours are very basic with most of the boxes a square nailed up tunnel with netting both ends. Mass produced and supplied by councls and local pest control NZ organizations. They are quite narrow with only abot 30mm of width left beside a T-Rex trap. (See pic)
My side kick has constructed a few boxes slightly wider, with a hinged roof overhanging the entrance hole.
Strangely, we have not caught a rat in this model yet, but consistently catch mice. (See pic)
The burrow with unknown occupants where we snared three weasels nearby has a mousetrap in the pic to help guage the size.
Cheers
The ones sold by councils and PFNZ clearly do the job very well.
I’ve considered investing in some myself, but I need to bite the bullet and do some more carpentry, so that I can start making my own. My tunnels would be customized to whatever trap model is being used and I’d make double-sets, instead of single-sets.
I’d stick with heavy timber bases, but I think that the sides and lid would be fine if they were plywood, making them far lighter to transport.
The pics didn’t show up!
I’m a big fan of tunnels with hinged lids. DoC double-sets have terrible swing-lids. I’ve given several of them hinged lids and it makes things so much easier.
I’m surprised that you haven’t trapped any rats in that tunnel. Small rodent activity should interest them.
Time and funds permitting, you could add more traps to the tunnel pictured. It’s clearly an above-average site, so the investment could prove worthwhile.
A second rat trap could go behind the white trap, with the trap entrance facing the side of the tunnel that the mouse trap is on (an L shape, basically). Between the 2 rat traps, you could leave a gap big enough to add another mouse trap. You would have to mount the traps in place, of course, because 1 active rodent could start a chain reaction.
That must be the burrow of a mouse or small rat. A UV torch would reveal the scent-trails, if that’s the case.
Cheers.
Good advise, and certainly worth doing.
Wow! Great posting, and the replies are also informative. I’m a big fan of the T-Rex trap. My first experience was with a single trap that was located inside the water cylinder closet in a rental house. thirteen ship-rats in 30 days - two within 90 minutes while watching the telly. It’s a very loud snap.
I now have 20 TR traps in tunnels set on my street. It takes about an hour if I check every trap and rebait the TR where mice have cleaned the peanut butter without tripping it. I put a piece of yellow electrical tape on the handle so I can determine if the trap was tripped from 5 meters away. Since I like to do a daily check (the neighbors have allowed me to enter their property) I can do a quick 10 minute walk and only service the ones that were tripped, then do the full hour every two or three days.
Sorry for not replying sooner, but the weather here has been great, so I’m trying to take advantage of it.
Those are crazy numbers with 1 snap trap!
Were you trapping mice/small rats with the trap, too?
Thanks for the compliment. I didn’t think there was much point in reviewing a trap if I didn’t go into detail and share my experiences with others. At some point, I’m going to revise the post, adding photos and more tips.
When you run out of the tape you’re using, I’d replace it with white duct tape, because it will be easier to see the traps from a distance and duct tape last for ages, because it’s strong, waterproof, and UV-resistant.
General trapping tips (feel free to skip these, because I don’t know how much experience you have and how much experimenting you’ve done).
Do you keep records? If not, it’s worthwhile, because it’s the best way to increase your trapping-rates. As a rule, a small number of traps will make up the majority of your kills, because they’re in the sites with the most rat traffic. If Tunnel A is averaging 15 rats per year, and Tunnel B at the neighboring property is averaging 3, add B to A. Over the course of a year, your kills will increase significantly. For one thing, you’ll start to get 2 kills per night, instead of 1. When 1 rat stops to investigate Tunnel A and is killed, the next rat is likely to investigate Tunnel B. With daily checks, you could/should make a way bigger dent in local rat populations.
If you can narrow down the sites with the most traffic, and combine tunnels at those sites, you will be able to check the tunnels much faster, making 8 stops, instead of 20, for example.
I wouldn’t use PB all the time, because rats like variety in their diet. PB’s a good lure, overall, and it’s a good, sticky base lure, but even squishing a sultana or a dried cranberry on top of PB could result in an uptick in kills. If a rat has had its nightly fill of protein and fat, a piece of sugar-rich dried fruit should be a more attractive lure than PB.
Rats love Nutella, so buy a small jar of off-brand Nutella and use it for a few weeks, instead. You could conduct a mini-experiment by using PB in every second tunnel and record the results for a month. Because you’re check 20 tunnels daily, you’d collect a lot of data in no time.
I haven’t tried this, yet, but avocado is reputed to be one of rats’ favourite foods, so I’d give that a go. One small avo would probably fill up all of your cups.
Because there will be pets at most of the properties where you have tunnels, presumably, putting animal fat in the TR cups would be risky in terms of interference, but you would probably experience a significant spike in kills.
Cheers.
Thanks for the additional information! I will try the fruit and maybe some Nutella if my wife ever leaves any in the jar 
I’ll also move a couple of non-performing traps closer to the most successful locations.
Yes, I’m getting mice in some of the traps (three this morning). Most of the time, they aren’t heavy enough to trip the mechanism, and once I had two that were sharing their last meal.
Yes, I’m using TrapNZ to record my activity and I keep the neighbors that have allowed me to put traps on their sections informed. There’s a young man up the street that said he’d like to help over the school holidays.
It should be pretty obvious which tunnels aren’t performing well, since you’re using TrapNZ already.
Before you move any tunnels, re-scout the properties that aren’t getting good results. There could be a lot of rat activity on a property that’s being missed, because the tunnel isn’t in the right place. Look at a property through a rat’s eyes, in terms of safe travel routes and things that may be of interest to them.
Outdoor buildings are excellent potential sites, because they give rats protection from the elements, cats and dogs, and they can be a good source of nesting materials and/or good spots to build a nest. Rats will eat artificial and natural fertilizers, and bags of seeds. As a rule, cluttered sheds/garages are better sites than tidy ones, because rats feel safer in them.
Good luck with the apprentice. You could always put him in charge of a few experiments, trying different lures and lure combos, re-siting tunnels, etc.
If they fit, you could put a mouse trap in the rear of some tunnels, behind the TRs. This will reduce interference levels, to some degree, and mice are excellent lures. I recommend the red and white traps sold at Mitre 10. You can mount them by drilling a small screw through the cup. If you put a mouse inside a TR, there’s a good chance that you’ll kill scavengers that aren’t interested in PB, Nutella, etc. If there are any weasels or stoats in the area, this would probably be the best way to trap them using snap trap tunnels.
Cheers.
Great read thanks. Am curious whether the meat would be better dried? I collect fat and scraps from sheep kills on the farm to use in traps so wonder about doing this to make it more long lasting? How big do you cut the meat pieces?
Thank you Andy for the comprehensive bait research paper.
Brodificoum was featured as a threat to morepork.
Nothing on the effects of pindone, a widely used pest control bait.
Very indepth and thorough research all the same.
Thanks for the compliments!
With TRs and other snap traps, I only use cooked meats and fats. The heat and the blowflies make using raw lures pointless here in spring and summer, and stoats and weasels dislike traps that smell like rotten meat (and they’re not alone!).
When I put cooked meat in TR cups, I cut it into square pieces that are about 10% bigger than the diameter of the lure cup. Because they’re larger than the cup, you have to squeeze the pieces in firmly. A big problem with using raw meat in lure cups, is that it shrinks as it dries, making it easy for predators to remove with their teeth or paws.
Before I put the meat in the cups, I put in some smooth peanut butter as an adhesive. The PB also acts as an “insurance lure”. If a predator is able to steal a piece of meat out of a TR, some PB will be left in the lure cup. Unless the thief returns right away to lick up the PB, the TR could still make a kill that night.
To make the meat pieces even more attractive to predators, I recommend giving them a coating of fat. Bacon or sausage fat will do. Putting some fat/grease onto the treadle past the lure cup makes the trap smell stronger and is another insurance lure.
Saturated white fat is the best lure that I’ve used, in any of my traps and tunnels. You could make your own supply of white fat, because you have access to all of those fat scraps, but you should look in your local supermarket/butchers’ store to see if they stock tallow, because it would save you a lot of time.
Do you use any DoC tunnels?
Cheers.
Hi there! I’m interested in the made2catch rat traps. Do you know of a local supplier for them? Many thanks!
You have to buy them from overseas. E-Bay and Amazon are probably the best sites to use. Even with the exchange rate and shipping, they weren’t expensive traps and they’ve proven their worth to me, killing some very large brown rats (450-500g).
Hiya!
I was just wondering if you have had an issue with getting the T-rex to set after a couple of catches? Mine doesn’t seem to want to stay open anymore/won’t click as I try to push the two ends together!
Ngā mihi :))
Kia Ora,
Yes, sometimes I’ve had issues with the T-Rex, and there are things to check:
- The small spring that lifts to trip mechanism may be “clogged” with excess bait and not lifting the plate.
- You may have accidentally dislodged the spring (I did once when cleaning the trap) and therefore the trip plate doesn’t lift up to engage the trip lever.
- The place where the catch lever sits on top of the trip plate may be worn and the trip lever doesn’t seat properly. I had this happen on one trap long ago.
I really like the T-Rex and have 30 of them set in tunnels. With salt air, the springs have rusted on some but it doesn’t affect the operation UNTIL the rust invades the rod that holds the trip lever - then the lever becomes stiff and the trap isn’t effective unless you have a 200+ gram rat step on it I haven’t found a way to clear the rust that impedes the lever from being depressed so I’ve had to replace the trap and send the old one to the land fill.
If you aren’t hearing a click, the arming mechanism at the back of the trap, which resembles a fishhook, has probably broken. It usually takes a long time for it to happen, so you might have used too much force once and it broke. If it has, the trap is toast.
It requires a lot less force to arm T-Rexes when they’re mounted down, in my experience, and I’ve found them to be far better mounted, anyways.
I’m also a fan of these traps - I’m the author of the post. I appreciate your contribution to problem-solving, Bud.
Apparently, one way that you can keep rust at bay, is to treat the springs with vegetable oil. A small paintbrush is the most accurate way to do this. Personally, I’ve never had to do this, because when my traps get rusty springs, they still function properly. In a wet climate or near the coast, oiling springs would be a wise idea.
An annual spray with WD-40 couldn’t hurt either. There’s a spray made with lanolin that I use on the springs of my Timms traps that works well and smells way nicer than WD-40.
Cheers.
We use Prolan (lanolin) on our traps - seems to work well and is easy to apply.