[Urban Wildlife Control Issue] Read the Signs

Features - Annual Urban Wildlife Issue

Whether you’re working to control wildlife, rodents or insects, it’s important for PMPs to notice the subtle clues in their accounts that can help them solve pest mysteries.

September 29, 2015

On opening day of North Carolina 2014 deer hunting season, my 10-year-old son David and I spent the day together in the woods hunting white-tailed deer. It was 17 degrees when we got out of the truck before daylight, and we made our way across a small field to the woods’ edge where we found our deer stand. I got all of our gear to the base of the ladder stand and had him climb up and get situated. I then proceeded in making three trips up and down the ladder to bring everything that we were going to need for the day. I never have taken so much “stuff” up into a deer stand in my life, but with a youngster you need to be prepared.

The sleeping bag was the most important piece of equipment that we had with us to keep him nice and warm, and of course the endless supply of snacks. David ended up killing his first deer that morning, and another one that afternoon. It was a great day in nature for father and son. During our long periods of waiting for deer to move by, I had David observing his surroundings, and pointing out the things he saw in the woods. He started closely examining the animals and the trees and seeing things that he had never noticed before. One of the things that caught his eye was when all of the small song birds quickly left the field and huddled in a thicket, you did not have to look far to find a predator such as a hawk or a fox. He also noticed how the moss grows on one side of the trees more than the other side. I want my son to learn to take notice of the small things in his surroundings to not only appreciate all of the biological wonders of nature, but to be able to understand how all of the animals and plants interact. We live in such a different and modern world now that we have forgotten a lot of the basic things that our forefathers knew about the environment around them.

Looking at animal tracks and trails can tell an entire story about what is going on at a particular time and place in the woods. As pest management professionals, we need to also practice the art of reading the signs that are around us every day at the homes and businesses of our customers. We may not notice subtle clues unless we take the time to observe and interpret what we see.

Wildlife signs.

Our company performs wildlife removal, and the beaver is an animal that we often deal with. This aquatic rodent leaves a lot of signs that can be easily observed. Anyone who has been around a beaver pond has seen the chewed trees and branches, or maybe a beaver lodge sticking up out of the water’s edge. A seasoned beaver trapper looks at the signs left by a beaver much differently than the novice wildlife observer. The trapper will observe how fresh the cuttings are, the direction of travel of the animals, about how many beavers are present in a given area, the underwater travel corridors as well as the land crossings. This makes the difference between being a successful trapper and someone who simply educates the beavers by improperly setting traps and alerting them to human presence.

When a PMP enters an attic of a home to solve a rodent problem, there usually are a lot of signs to read. One of the difficult things is to separate what is current from what is old. Because an attic is rarely entered or disturbed by humans, the gnaw marks on the rafters and the droppings present in the insulation give a historical perspective of the life of the house since it was built. Since grey squirrels, flying squirrels, several species of mice, as well as Norway rats and roof rats can all call an attic home, it takes a keen eye and thorough investigation to determine the type of rodent that is causing a problem.

In these cases it can be helpful to interview the person living in the home and determine what they are hearing or seeing and the time of day the activity occurs. Many times this information can help narrow down the possibilities. Do not be quick to disregard what the homeowner is telling you. Even though they are not trained pest control personnel they can provide valuable information that can be vital in solving the problem.

Rodent Signs.

Rodents can be some of the most challenging critters that we as PMPs have to deal with. We hardly ever see the animals when we are making our initial observations. We must be able to read the signs that the animals have left for us and we should be able to interpret what we see at the time of inspection to determine the problem. We then take the information gathered and determine a course of action that will ultimately solve the problem.

I remember a Norway rat that consistently was eluding our snap traps in a home; One of our technicians asked for help. This client had called us because a rat had chewed the electrical wiring in the kitchen stove on two occasions and he had tried unsuccessfully to trap the animal himself. Not only did we have a rat that had lived in the house for quite some time, but we had one that also knew very well what a snap trap looked like. I went out with the technician to the home, and performed an inspection in the same areas that he had been trapping. It looked like our technician had done a good job of covering the house, however I happened to notice some shredded up paper material in one section of the basement drop ceiling. I took a sample of this paper back up into the kitchen and matched it up to the pattern of the paper napkins in the drawer next to the stove. The rat had been sourcing nesting material out of this drawer.

This gave us an important clue as to the travel path of the rat from the kitchen through the drop ceiling. We went back to the basement and set a single, non-baited snap trap and covered the trap with the shredded napkins. We then wedged a board sideways in the drop ceiling to funnel the rat across the pan of the trap. We had a dead rat the next day, and a very happy client. By hiding the trap and controlling the path of the animal, we had put the odds in our favor.

Insect Signs.

There are many “signs” that we need to train ourselves to look for on the insect side of pest management. With the development of baits for cockroaches and non-repellent insecticides to use on ants, we as an industry have made huge strides in developing strategies that make these insects much easier to control than in years past. Even as good as these chemicals are, there is no silver bullet. These insects can still leave us scratching our heads on occasion. Ants leave signs for each other all the time through trailing pheromones that are not visible to the human eye, however, if we closely observe trailing ants during our inspections, we often can determine where these ants are coming from within the structure. More importantly, we can also determine how and where the ants are entering from the outside.

Learning to identify certain plant species that are frequented by aphids around homes and commercial buildings also can help in locating ant colonies that are sourcing the honeydew that aphids produce. These plant species are like digital billboards to ants advertising that there is a highly digestible, energy-filled meal available. Observing rock formations, stepping stones, bird baths and buried downspouts are all important for the technician attempting to locate ant colonies. All of these items can contribute to ant nest harborage, and should be instantly recognized by a technician as a sign that ants might frequent these locations.

Cockroaches leave visible evidence through their droppings and aggregate in large numbers, causing dark fecal focal points. In low numbers, however, they can be difficult to detect because of their cryptic nature. The use of glueboards can be helpful in providing not only a catch and removal tool, but more importantly what can be learned by the species of cockroach caught, the number captured and which side of the trap they were captured on.

I remember many years ago I received a call from a homeowner who had been battling “American cockroaches” in her home for many years. She had been told by another company that they were coming from the basement. She hired our firm, and we assigned a technician to the account.

In a few days, the client called and she had found a dead cockroach on an insect monitor that our technician had placed under the kitchen sink directly over the basement. The technician and I went to the home and upon observing the roach on the monitor saw the “American cockroach” was actually a smokybrown cockroach. I asked the homeowner if anyone had been in the attic recently and she stated that no one had been up there in years. She took us up two floors and pulled out a long wooden stick with a hook with which she pulled down a door with the longest set of retractable stairs I have ever seen. The technician and I entered the attic and observed a moving mass of smokybrown cockroaches. There were so many that the rafters were crawling with them. We shut off the air handling unit, closed ourselves in the attic and started applying insecticidal dust.

We were immediately run out of the attic by a bunch of angry European hornets that we had failed to see on our initial inspections. Upon exiting the home to locate the hornets’ nest in the roof soffit, we observed hundreds of smokybrown roaches climbing out of the attic and onto the roof in a attempt to escape from the dust. They were taking flight and landing in the yard in large numbers. Because we were able to properly identify the insect, and use our knowledge of this insect’s behavior, we were able to solve a customer’s problem. (Please note that a thorough inspection always should be performed at the beginning a new client’s service, and if we had done so initially, we would have most likely detected both the smokybrown cockroach and European hornet issue.)

Of all the insects that we deal with as a company, the bed bug to me is the most challenging insect to read the signs. Although the insect in large numbers is fairly easy to detect through droppings and visible observation, in low numbers this insect is extremely difficult to detect. I have read statistics where the best human bed bug inspectors may be as low as 30 percent accurate in detecting bed bugs in low concentrations. The eggs and first few stages of the bed bug are extremely small and translucent, and when found are usually secreted in secluded and inconspicuous areas. To help with this process, we utilize bed bug detecting K-9 teams. The dogs can read the odor signs that the bed bug and eggs emit when humans cannot. There is even a different odor when the insect is dead. This is particularly useful when determining whether or not a bed bug treatment was successful.

A good K-9 handler is adept in reading the physical signs shown by the dogs as they cue in on live insect odors. By having a good knowledge of animal behavior, an experienced dog handler has the ability to interpret small changes in the way the dog is working to not only ensure the dog is working correctly, but to determine when the dog catches the scent of a live bed bug or egg. Although trained bed bug dogs are not 100 percent accurate, they are much more accurate than any other detection tools we have at our disposal.

The signs and clues in our accounts are there waiting to be discovered. It is up to us to train our eyes and minds to recognize the difference between the ordinary and the exceptional. As in many things in life, there are only subtle differences between success and failure. The pest management professional who has attention to detail, and trains in the art of “reading the signs” will benefit professionally — as well as personally.


Frank Fowler is vice president at McNeely Pest Control, Winston-Salem, N.C.