A lure that I highly-recommend experimenting with is tallow, which is pure, saturated beef fat that comes in blocks. Most large grocery stores will stock it. Here’s why tallow deserves a go:
Tallow is dense and wax-like, so it can be sliced into pieces or shavings. The warmer it gets, the greasier it gets, so I cut it up when it’s cold. After a while, your hands can get greasy, so using gloves is a good idea.
Tallow smells like roast beef or lamb drippings, so its odour is very attractive to fat-seeking predators. Its smell is temperature-related, but even when it’s cold, the predators where I trap have been quick to find it. When luring rats, the fattier the lure, the better, so tallow should be the ultimate edible lure.
Its greasy surface makes it waterproof, so tallow can withstand the elements better than most lures.
Being waterproof, and containing no water, tallow is mold-resistant, making it an excellent lure to use during wet and humid weather, and by bodies of water. Tallow can go moldy if it’s contaminated by a moldy lure, so try to place it on/in clean traps. Depending on predator populations, leaving traps and/or tunnels unarmed for a little while will allow predators and insects to do most of the cleaning for you.
Unlike flesh lures, blowflies can’t lay eggs on tallow. This is a huge advantage is spring and summer, when maggots can destroy lures in no time. I haven’t tried this, but it’s possible that coating a flesh lure with tallow might keep blowflies away, because they’re seeking lean flesh.
Because tallow is pure, saturated fat, I’ve found that the amount that predators consume per visit is relatively small, so my pre-feeds last much longer than with standard lures. As evidenced by the large toothmarks often left in it, and the amount of tallow that’s gone, the amount of tallow that a large rat will consume per visit is equivalent to a large pea. In a full snap-trap bait cup, a large rat should require 3 visits to eat all of the tallow.
Like larger predators, the amount of tallow that mice consume per visit is also much smaller, compared to standard lures. This increases the odds that rats, mustelids, and hedgehogs predators will find traps containing lures. Because mice and small rats have to visit the tallow several times to eat the tallow, they create more scent-trails and leave more physical evidence, which lures other predators to the trap(s).
I haven’t seen any evidence that invertebrates consume tallow. Some insects will, but tallow’s dense, fatty texture makes it harder for them to eat or harvest. The appeal of tallow appears to vary between species, and some insects may not be able to eat or harvest it. For example, cockroaches and weta devour PB, but I’ve only seen ants eating tallow.
Tallow has the potential to increase the chances of bird by-kill, but I haven’t trapped a bird using it, yet. All of my traps are inside tunnels, however.
It’s cheap to buy, and a block can last for a long time. Kept in the fridge, tallow can stay good for up to a year.
I’ve trapped dozens of ship rats and brown rats, 3 weasels, but no HH, so far.
The stoat and weasel populations in the area are abnormally low. The unseasonably cool temperatures, and above-average rainfall, may have played a role, and the strongest frost we had all year was 6 weeks later than when frosts would normally have stopped.
Also, the yellowheads, chaffinches, and welcome swallows that normally return to the area in early December, due to the hot, dry weather starting, haven’t shown up. That’s a lot of eggs, chicks, and nesting adults taken off the menu.
The strong frost, bad weather, and reduction in their food supply, may have killed quite a few adults, and resulted in a high death-rate of the kits that were born.
I’ve purchased the tallow that I use at my local Pak 'N Sav in Napier. Blocks there cost about $8, and tallow goes a long way.
You should ask somebody in the meat and fish dept. about tallow, but if large supermarkets don’t stock it, I’d be surprised if it wasn’t available at Mad Butcher’s. You may need to ring a few local shops to find out. I hope that you manage to find some.
Before I started buying tallow, I would use the white fat that solidifies on top of the jelly from roasts, and bacon fat. They’re all very effective, but only if you’re operating a small number of traps close to home. They aren’t purified fat, so they will go moldy in wet/humid weather.
Whether or not a rats are likely to sample lures that have been colonised by mould, will depend on several factors.
A) How many rats where you’re trapping have eaten mouldy food?
Mould is toxic to rats, so if they’ve sampled mouldy foods that have made them ill, they will avoid it. Rats that haven’t eaten mouldy foods before can be trapped, but the % of adult rats that haven’t eaten mouldy food before is probably quite low. If you trap rats in DOC tunnels that contain mouldy baits and eggs, it’s safe to conclude that the eggs were responsible for the kills…
Bait companies instruct people to dispose of mouldy baits, because rats no longer find them attractive, and Victor recommends removing mouldy lures from traps.
B) How mouldy are the lures?
During pre-feeds in DOC tunnels and on snap-traps, rats will ignore the mouldy sections of lures, and eat the sections that haven’t been colonised yet. Will rats risk eating lures if the mould levels are low? It would depend on how attractive the lures are to them and how hungry the rats are. Rats often ignore traps that have fresh lures in them, because they don’t like the food, or aren’t hungry. What are the odds of a discerning rat with good food supplies stopping at a trap with a mouldy lure?
Studies would have to be done to determine rats’ interaction-rates with mouldy foods, but I would expect them to be very low.
B) Moulds produce foul odours, which will compete with the attractive odours of lures. Mould(s) can colonise lures with great speed in wet and humid weather, so the foul odours that they create will intensify every day, while the attractive smells of most lures will weaken every day. It won’t take long before your traps/tunnels repel rats, instead of attracting them. Given their powerful sense of smell, rats will be able to smell mould from a considerable distance away from a trap/tunnel.
Thanks for all of that, now I know. I’ve been mixing peanut butter with cocoa powder which appears to last longer though I have not done a proper test in all conditions.
Tallow sounds promising I shall have to check out our local Mad Butcher.
I haven’t tried mixing PB with cocoa powder before, but it’s a cheap and easy way to create a Nutella-esque lure. What’s the ratio of PB to cocoa in your recipe? I’m going to make a batch.
Adding cocoa will dry out the PB somewhat, which explains why it will stay good longer in wet/humid weather (more moisture = a higher rate of mould colonisation). This lure will last even longer if you give it a coating of cocoa when it’s in/on a snap-trap. Cocoa is really dry, so mould won’t colonise it until it accrues enough moisture. Cocoa is a poor source of nutrients for mould, too, so it should grow slowly.
In dry weather, the cocoa will prevent PB from going stale quickly. Once a rat licks off the cocoa coating, the PB in the mix will taste and smell fresh compared to PB that’s been exposed to the air for days.
It’s possible that coating your lure with cocoa will also reduce interference by I&I), while still appealing to rodents. With a coating of cinnamon on apples, ants stay away until they start to ferment. Cinnamon apples are good possum lures in snap-traps and in tunnels for ship rats.
Aside from cocoa, other dry spices and herbs should also work. Dill? Ginger? Mustard? Nutmeg? Cloves? A mustard lure is on my to-do list, because I have a hunch that it will be successful.
For predators looking for meat, try mixing PB with Goodnature’s Meat-Lover’s lure. It’s waterproof, mould-resistant, smells like blood, is long-lasting, and I&I don’t like it. It’s an excellent lure on its own in snap-traps, but some rats can lick it up easily, so a PB mix will make it harder for them to eat.
I hope that you manage to find some tallow, and that you manage to duplicate my results.
The peanut butter I use is very runny so I just put in a few spoonfuls of cocoa powder in to make it so that it does not run off the bait plate, so I don’t really have a recipe. I can tell you that hedgehogs and mice like it but we’re lucky to now have removed all the rats and possums from both the Millennium and Library Reserves here on the Otago Peninsula. We’ve not caught any for at least 18months.