I’m pretty sure I saw a rat on our back deck last night so I was trying to find a burrow or some other evidence. I might have found the rat’s travel route at the back of the house. What does a rat’s runway look like?

D. H., Candia, NH

Rats are creatures of habit and will follow the same route between their nest site and food and water sources. After much repeated use, these paths or runways become more obvious. Runways of the brown (or Norway) rat are mostly near ground or floor level and are usually near some vertical surface like a fence or wall, steps, or rafters. Runways usually follow along an edge or manmade lines such as along baseboards or pipe runs inside, or around large objects such as boxes and equipment. Outside, runways may follow fence support rails, deck ledges, or foundation walls, for example.

Dark Rubmarks Help Identify a Rat’s Runway

Rat runways that are well used will have dark, greasy rubmarks along side walls or baseboards when inside. The rubmarks are from an accumulation of oils and dirt from the rat’s fur. You will also find the dark rubmarks at points where a rat repeatedly squeezes through an opening or swings over a rafter or beam. Fresh rubmarks are soft and will smear if rubbed. Rubmarks that have been there for a while and indicate a runway that is no longer in use will be dusty and will flake off if scratched with a fingernail. You may also find rat feces (droppings) along the runway. Spider webs and dust in an indoor runway are indications that it is no longer in use.

Active Runways Are Kept Clean and Clear

Outdoor rat runways appear as smooth, beaten-down dirt paths that are kept free of vegetation and debris. If the paths are not clear, they are probably no longer being used. Runways may lead to an outside ground burrow that will have hard-packed soil around the entrance hole, unless newly dug, and rubmarks may be visible around the opening. The opening of an active burrow is likewise kept free of leaves and debris (see Could Those Be Rat Holes?).

You can further confirm that a particular area serves as a runway route by placing a “tracking patch.” This is simply baby powder, flour, or similar nontoxic fine material that is lightly dusted along the route, usually indoors. If rats are using the site as a runway, you will later see footprints or tail drag marks in the tracking patch if you shine a flashlight across the patch at a low angle. Outdoors, if conditions are right, you may be able to briefly see rat footprints in soft soil or snow.

Or, you can call Colonial Pest for help in tracking the elusive rat in your yard or home. Our trained technicians know what to look for and will conduct a full inspection and set up a rat control program with guaranteed results. Call Colonial today!