Minty smells are attractive to many animals.
Menthol, a primary component of peppermint essential oil (Mentha x piperita), shows potential as a natural anthelmintic agent against various roundworms (nematodes) by disrupting their nerve function, particularly in laboratory settings. Studies indicate it can act as a positive allosteric modulator on nematode nicotinic acetylcholine receptors (nAChRs), causing paralysis and death.
This means eating mint and possibly other similarly smelling herbs is effective against intestinal parasites. The volatile bioactive substances also get into the bloodstream and are partially excreted through the skin. So hypothetically, animals must really benefit from consuming such antiseptic plants with lots of volatile compounds that are
nontoxic and non-bitter, like mint (and unlike wormwood, for instance).
Also, one of the key "uses" of these substances by animals - and a really insufficiently studied one - is self-anointing. It is different from marking behavior. Rats are a good example. If you give anything minty-smelling to a rat, it will chew it up, mix with saliva and rub it into its flanks thoroughly. Rats utilize mint, menthol, eucalyptus, as well as shilajit and even tobacco for this purpose. Hedgehogs self-anoint in the strict-sense, too. Bears, too (they have been observed to chew up certain herbs and rub them into their fur), which is more relevant for marten lures because phylogenetically bears are in the same clade (Caniformia) as martens, while cats are in the Feliformia.The key function of self-anointing is believed to be ectoparasite control, and antibacterial/antifungal properties = better wound healing and better adaptation to denning in cold, wet, moldy conditions (a hollowed-out tree trunk is not really as cozy, warm and dry as Beatrix Potter would make it look).
I add menthol to my sable lures. L-menthyl lactate is another substance worth investigating.
Yet another one is thymol, the main component of thyme flavor. Beekeepers know thymol as an effective and safe medicine agains varroa mites.
A trailcam study of the effect of these substances would be interesting, especially if the animals could take and chew up the scented bait (cotton balls?).
