Do you know all of the indicators to be looking out for during a rodent inspection? Read more below.

As with any integrated pest management process, a thorough inspection must be undertaken before you can even think about treatment. In the case of rats and mice, the quality of information gained in the initial inspection will help determine the best solution – often making the difference between a success and failure.

For example, if rats or mice are living outside the building and entering through a hole in the brickwork, why waste time and money by installing a number of bait stations in and around the property? A few minutes of effort to identify and block the entry point and the problem is solved. The rodents are now outside and hopefully go somewhere else to feed and you can go and offer your services to the neighbours!

So what should you be looking for during a rodent inspection?

Rodents (dead or alive!) – actually seeing rodents alive gives you confirmation of the infestation and a chance to confirm identity of the rodent causing the problem. Also, look for dead bodies in the roof and sub-floor as this may indicate a long-term problem. Don’t forget to ask the homeowner where the rodents have been seen.

Droppings – look at the texture, size, shape and quantity of the droppings. Shiny, black and gleaming? Then they are definitely fresh. Grey, dusty and crumbling? Then they are old droppings. However, be aware that droppings can dry out rapidly in hot roof voids. You can tell the species by the shape and size, but be warned that the differences between roof rat and Norway rat droppings are not always clear cut.

Tracks – Footprints and tail marks betray rodent activity. Sometimes you can dust flour lightly over the floor and detect marks the next morning.

Smear marks (also known as ‘rub marks’ or ‘grease marks’) – these are made when the rodents come in contact with hard surfaces over a period of time, with oils from their fur rubbing onto the surface. They will often be found around entry points, indicating locations that will need to be sealed (shown in main picture, above). Smear marks will last for years in an undisturbed environment so are not always conclusive proof of current activity.

Gnaw marks – these are usually quite obvious and can be found where rodents have chewed through materials to gain access to foodstuffs or nesting sites, or where they are simply gnawing to keep their incisor teeth at a manageable length.

Burrows – are predominantly made by Norway rats, but sometimes mice and roof rats can also make burrows. Previously, an enormous infestation of roof rats was found in a poultry farm where they were living in burrows dug into the piles of chicken manure! However, Norway rats are the main ‘diggers’ and burrow into creek beds, manure piles or simply into the soil, usually covered by tall grass or weeds.

Nests – locating roof rat nests is often difficult as they are normally hidden away in roof voids or other obscure areas. Mice nests are more commonly located, as they are more often in living areas, behind cupboards or in furniture.

Sounds – these are normally heard in the evening or dawn when the rodents come out to play and usually emanate from the roof void. The rule is: mice sound like rats, rats sound like possums and possums sound like elephants!

Smell – there is a characteristic odour associated with rodents and cannot be mistaken for anything else. It is a sickly sweet, cloying odour that lingers after the rodents disappear.

Stock damage or consumption – rodents consume around 10% of their body weight a day, but destroy or contaminate much, much more. Any packet, carton or bag that has been damaged must be discarded and is a direct loss to the owner.

Urine stains – these are not visible to the naked eye and only show up when exposed to ultraviolet (black) light. You need a UV source to find them, but be aware that other organic substances will also ‘glow’ giving a ‘false positive’.

Once you have all the information you can derive, you will need to draw up a treatment plan. In cases where you need to present a quotation to a prospective client, the inspection will help you to create an accurate costing. There will always be somebody who will offer a ‘better’ deal, but if you can act in a professional manner by quoting the correct number of bait stations, proofing materials and labour costs, you will (hopefully!) gain a reputation as a responsible rodent expert.

If you are struggling on a rodent job or need help to prepare a quotation, then you can always call upon the services of the trained staff of Globe Pest Solutions or a representative from a rodenticide manufacturer.