Most homeowners believe that if they have a mouse or rat problem, they will easily be able to spot the problem. However, both mice and rats have the tendency to stay hidden, only coming out to look for food and explore when they feel it is safe. Plus, rodents will not typically build a nest in a spot where there is a lot of human activity. The air ducts in your home make the ideal nesting spot for rodents because ductwork is typically tucked away in an unused location, such as the attic or crawlspace. Here are a few sneaky signs that you could have a rodent issue in your ducts. 

The air flowing through your vents has a specific type of odor. 

Rodents have no qualms about using the same area where they nest to urinate or excrete droppings. Therefore, a strong and precise odor will develop from even a small population of rodents. If you experience an odd ammonia odor with the air that is radiating through the vents in your home, it could easily point to a rodent problem. 

You have vents that seem to not be producing as much air flow. 

You have some vents in your home that provide a nice burst of cool air when the air conditioner is on, but some rooms seem to be getting much less air flow and may stay at a warmer temperature. While this almost always points to damaged ducts, the damage could be caused by rodents. If this is a problem you are experiencing, grab a flashlight and navigate to the system of ducts in your house to see if you spot any signs of chewed openings or holes. 

There is extra evidence of debris around vent registers. 

Mice and rats will use just about anything they have available for bedding material to keep comfortable or protect their offspring. Tidbits of paper, small fragments of insulation, and even tattered pieces of cloth are all examples of preferable bedding material. If you start to notice an excess amount of debris around the vent registers in your home and it seems to be coming from the vent itself, it could easily be a sign of a rodent population hidden away in your ducts. 

If you suspect you have a rodent problem in your ducts, call up a pest control agent to help you track down the critters and get them eliminated. Then give a duct cleaning or HVAC professional a call to help you make the necessary repairs.