Handbook Contents | Best Practices Learning Objectives | Assess the Situation | Choose Management Options | Tools and Techniques | Preventing Problems | Evaluating Success | Resources | ICWDM | Wildlife Species Information
Step one: Assess the situation
The very first thing you need to do is find the source of the customer's problem. That means you'll need to understand the type of damage and how bad it is. You have to identify the culprit. You'll look for clues that will help you figure out what attracted the nuisance animals to the site. (Remember the two key enticements, food and shelter).
Signs of wildlife presence
Wild animals usually provide numerous signs of their presence. Once you've gained experience in "reading" these signs, the clues you gain from your site inspection and customer interview should help you identify the species, estimate the number of animals present, and find the areas where they're most active.
Raccoon entry through attic vents.
- Visual sighting. This is one of the easiest ways to identify the species (if you can trust the observer). You may also find carcasses. If nocturnal animals are often seen during the day, this may mean that the animal has young and is feeding more often, or that the local population is high, especially with rats and mice. If dealing with a bat colony, you may quickly identify the species but have a harder time locating the entry holes. You can use this to your advantage. Stand outdoors at dusk or dawn, and watch where the bats enter or leave the building. There's the hole!
- Sounds. Various squeaks, growls, cries, hisses, chitters, screeches; gnawing; or clawing, scampering, and climbing inside the walls, above the ceiling, between the floors, or underneath cabinets. Learn to tell the sounds of adults from those of young.
- Odors. You may smell the droppings, fermenting urine, or body oils of wildlife that are living indoors. With a little experience, you can tell the odor of a house mouse from that of a rat. Skunks have a well-known scent, but woodchucks can also be told by their odor. Dens of other animals, including raccoons, have their own perfume.
- Droppings may be found along runways, near shelters, in piles near an entry hole, or in other places used often. Fresh droppings are shiny and soft in texture, while old ones are dry, lighter in color, and hard. Old droppings crumble easily.
Left: You'll often see a pile of bat droppings under the main entry hole. Right: Notice the urine stains on the chimney (from bats).
- Urine. You can see rodent urine using an ultraviolet light—it glows blue-white. Unfortunately, other materials also do this, which can be confusing until you become familiar with the typical background fluorescence of a home or office. You may also notice discoloration on building materials, often in attics or crawl spaces. That's caused by a large amount of urine, which could indicate the presence of raccoons, flying squirrels, or a large bat colony.
- Nests and food caches can sometimes be found when cleaning garages, attics, basements, closets, and other storage places. Rats, squirrels, and other rodents often store food in attics.
- Entry sites (holes, cracks, loose siding). The location, size, and condition of the entry sites are important clues to the species involved.
- Burrows. Woodchucks, chipmunks, moles, voles, and Norway rats burrow, and you can learn to tell their burrows apart. (Other animals, including raccoons and skunks, will use burrows but they don't make them). The location of the burrow, its size, the type and number of entrances, and objects located near the burrow will help you identify the species.
- "Leftovers." You'll sometimes find the remains of a meal near an animal's den. You may be able to identify what the animal was eating, and that can help you identify the animal using the den. For example, you'll often find a fair amount of prey remains, such as rabbit fur, near the den of a fox or coyote. If there's no sign of prey, then you're probably dealing with a herbivore, such as a woodchuck.
- Runs. Smooth or worn trails may be found next to walls, along fences, or under bushes and buildings. Runs within buildings may be well-polished trails that are free of dust. Trails through insulation are common.
- Smudge marks are often seen in the animal's run where it rubs against a surface during its travels, leaving behind dirt and oil from their fur. Look on pipes, beams, against walls, and on the outside edges of holes.
Left: A raccoon climbed this pipe to gain entry to the attic. See the marks? Right: Buildings are vulnerable at their joints. Check carefully for smudges that show an animal's been going in and out.
- Tracks and claw marks. Footprints, tail marks, and wing prints may be found in dusty surfaces, sand, soft soil, and in snow. If the surface doesn't show tracks well, you can sprinkle nontoxic tracking dust (such as chalk powder, flour, or unscented talc) in a likely area, then return later to see if there are any tracks. When used outdoors, the dust must be protected from wind and rain. You may find claw marks on woodwork, trees, or in dust. Consider photographing and labeling the images (after you're sure you've properly identified the species).
- Hair, feathers, or shed skins. You may find tufts of hair on a fence or baseboard, feathers in an attic or above a dropped ceiling, or, less often, the shed skin of a snake. With practice, you may be able to identify the species from this sign. To improve your identification skills, consider making some hair sample charts. Clip a tuft of hair from a nuisance animal you've dispatched, and attach it to the chart with the species identified.
- Gnawing (wood chips, tooth marks, holes, shredded fabrics, frayed wires). Look for evidence of chewing wherever wildlife might try to enlarge a crack or enter something. Wood chips may be seen near baseboards, doors, basement windows, kitchen cabinets, furniture, and stored materials. You could find shredded clothing, or see toothmarks on pipes. Rodents and raccoons often chew on the insulation around wires. The size of the toothmarks (or of a hole chewed in a baseboard) will frequently help you tell whether you're dealing with rats, squirrels, or mice.
What happened here? A squirrel, trapped in a basement, tried to chew its way out. Left: the squirrel tried to squeeze underneath the door that led to the basement, gnawing and scratching at the bottom of the door and the rug. See the bits of wood and shredded fabric? Right: It also chewed on the window in the basement, hoping to escape that way. The squirrel chewed most of the mullions down to bare wood. See the bits of wood on the ledge?
- Pets become excited. When cats or dogs hear or smell rodents in some inaccessible spaces such as a wall, they may become enormously interested, whining, sniffing, and scratching at the spot.
- Access routes. Walk around outside and try to imagine the route the animal might have used to gain entrance to the building. Are there trees or utility lines near the roof? Could it have crawled under a porch, up a chimney, or along a downspout? Is there an attached garage that might have been left open? These clues point to likely culprits. Skunks, for example, aren't going to jump from a tree branch onto the roof, and squirrels aren't as likely to wriggle in underneath a porch.
Information that you would gain from interview and inspection
Your knowledge of the habitat preferences and behavior of wildlife will help you estimate how many animals might be present. For example, if your customer complains of noises in the attic in March, you're probably expecting to find squirrels, and not just one—probably 3 to 8, because that's when female squirrels are raising their young. (If you see a female mammal, you may be able to tell if she's nursing because her nipples would be larger. This is hard to see on some of the small, fast-moving animals like flying squirrels. So if it's the breeding season for that species, assume that young may be present. And be careful, because individual animals may give birth outside of the textbook breeding season.)
Other aspects of the animal's lifestyle that help you answer the question, "how many?" include its social habits (generally found alone, or in a group?), daily movements, and whether or not it hibernates or migrates. How fresh are the signs? Is this problem new or is it well-established? How large is the property, and how many individuals of that species would you expect it to support?
But you're more than a wildlife detective. You also have to nose around in your customer's home, and ask questions to find out if the inhabitants (or their neighbors) are causing the problem. People sometimes feed or house wildlife without realizing it. Squirrels, for example, may be attracted to spilled seed at a bird feeder. Maybe not a big problem. But once nearby, they may run across the roof and find a hole that gives them access to the attic. Perhaps they decide that's an ideal place to raise their young. To solve this conflict, you'll probably need to remove the food source and repair the building.
There are other things you need to know about your customers before you choose a strategy, such as whether or not there are any pets roaming freely in the area. So, Sherlock, how do you proceed? Most NWCOs interview their customers and inspect the premises to look for clues.
Here are the questions you'll hope to answer with clues gained from the interview and the inspection:
- Which wildlife species is causing the problem? Is there more than one species involved?
- How many individual animals might be present?
- Could there be young present?
- Is this the first time they've had a wildlife problem? If not, what happened before?
- How long has this problem existed?
- Are the culprits readily accessible, or hard to reach?
- How risky is this situation for you, your customers, and their neighbors?
- Can you target only the offending animals?
- Will it be easy to be discreet, or would your control activities be in public view?
- If you repel or exclude the animals, where might they go?
- Does this look like a short-term problem or one that's likely to happen again and again?
- Given the location of the site, are there any local laws that would affect your management options?
- In addition to this problem, do you see signs that could predict future problems?
First, it's best to talk to the right person—whoever knows the most about the problem and the property. Ask both general questions and some very specific ones. A general question might be, "Please describe what you know about the problem," or "Have you noticed any problems since my last visit?" This type of question gives customers a chance to share their information. That could trigger other questions that might guide your inspection.
You'll develop your own interviewing style, but here are some questions to probe for specific information. Ask the customer, when did you first notice this problem? How often does it happen? Did you see any animals or any signs of animals? You might want to prompt them, by asking whether they've heard noises, for example. Then be sure to find out if the noises are heard during the day or at night. Can they locate the noise? You may want to ask several questions about the noises they're hearing, because sometimes people mistake mechanical sounds such as the beeping of a smoke alarm that has a low battery or a swaying utility line for animal noises.
Remember to ask if they've ever had any trouble with wild animals before. If they say yes, have them describe that situation in more detail. When did it happen, did they identify the culprits, and what did they do?
There are also a few important questions to ask about the household. Are there any children or pets present? That might limit which wildlife control techniques you choose. Did anyone have any direct contact with the wild animal? What about pets? This is especially important if dealing with bats, raccoons, and skunks, the species in our area that are most likely to carry rabies. If there's been contact, you'll have to follow health department guidelines. That's the law.
Before you can confirm the problem and contemplate solutions, you'll usually need to inspect the property. Take a good look at the whole landscape, and the neighborhood. This is the big picture that could explain why the problem developed. With the added information from an inspection, an experienced observer can provide management options for problems associated with uninvited animal guests.
Follow appropriate safety precautions throughout the inspection. Before you start your inspection, think about the space you're entering and the typical hazards associated with it. In an attic, you might worry about heat stress; ladder accidents; airborne diseases stirred up from rodent, bat, or bird droppings; and scratches from nails that might expose you to tetanus. Heat stress and airborne diseases are also concerns when entering a crawlspace, but you may not encounter nails or need to use a ladder. (See chapter four).
Find out where the property lines are, and whether the caller owns or rents. If it's a rental, talk to the property owner or manager to secure permission. (If the renter refused to pay, the managers might not be willing to if they didn't authorize the work.)
During your inspection, you might focus on the specific problem area but there are some benefits to inspecting the entire building or property. A "problem-specific" inspection takes less time and addresses your customer's immediate concern, but a more thorough inspection may identify other problems that your customer doesn't know about. For example, you might be called for raccoons in a chimney and find that the animals have also entered the attic. Or maybe they haven't made it into the attic, but you suspect it's only a matter of time because the type of roof vent on this house is very vulnerable to raccoon damage. Rotted soffits, trim, and roofs are also vulnerable to animal entry.
A thorough inspection will also reduce the likelihood of overlooking some aspect of the current wildlife problem. What if there's more than one species involved? Even if the customer didn't ask you to look for that, they might not be happy if you missed it.
Detective tools (inspection equipment)
- good flashlight with extra batteries and bulb
- small, flat pry-bar
- stepladder, larger ladder
- binoculars (useful for tall buildings)
- mirror, TV camera, or fiber optic scope attached to a long, flexible pole (for viewing hard-to-see areas such as wall voids)
- ultraviolet light for detecting rodent urine stains
- digital or instant camera (so you can show your customer exactly what you found)
- inspection form for recording information
- identification guides, including those that show animal sign (tracks, scat, nests)
- plastic bags for collecting animal sign (to show evidence to customers)
"I had a job where a raccoon was living in one of two spaces in the attic of a large house. If I'd limited my inspection to the area where the customers regularly heard the raccoon making noise, I would have missed the actual entry site. This raccoon got into the building through a hole that wasn't visible from the outside. Then it traveled through a small wall void into the second crawlspace area, where it was most active."
—Lynn Braband, former NWCO in New York
Take pictures during the inspection, using a digital camera or instant camera so the images are available right away. It's much easier to explain the situation to your customers if you can show them pictures of the damage, the animal sign, and the entry holes. In fact, you may want to create a photo album that shows structural problems, typical animal damage, management options, and prevention techniques. That's a handy resource to keep in the truck. Consider offering fact sheets to customers, too. This could save you time while reducing the odds of misunderstandings. (Make sure the information is reliable! Dependable sources include the state wildlife agency, health department, and Cooperative Extension.)
It's just as important to take notes during the inspection. Write down your management recommendations, either on the inspection form or the contract. Give the customer a copy of the inspection report and remember to keep one for yourself. Once you've reached agreement on the approach, you and your customer may want to sign a contract that clearly describes the work, your fees, and terms of payment. Many NWCOs also collect a deposit at the beginning of a job, although this is usually most practical with private individuals. Different arrangements are often made with corporate accounts.
Another tip that may save you time later is to be systematic as you conduct your inspection. It's easier to remember whether or not you've checked a particular area if you always work in the same pattern. After you've done a few inspections, you'll develop your own style. Here's an example of a thorough inspection of a building for existing or potential wildlife problems.
Start inside the building at the top and work your way to the bottom. Within each room, move either clockwise or counterclockwise. Pay special attention to the corners, and spaces underneath and behind furniture. If there are suspended ("dropped") ceilings, push up the panels in a few places to check above the ceiling. Inspect attics; basements; the areas underneath sinks; the places where pipes, cables, and wires enter the building; and crawl spaces. Look inside closets and built-in drawers.
Use light to your advantage. During the day, turn off the lights and look for places where the daylight shines through walls and floors. If light can get through, so can some small animals.
Once you're done with the inside of the building, move outdoors. You can use light to your advantage here, too. At night, turn the lights on, then go outside to see if there are places where the lights shine through the walls or roof. Again, start at the top and work your way down. Use binoculars for a good view of the roof.
What's the condition of the eaves, dormers, windows, vents, ledges, chimneys, and roof corners? Animals often gain entrance at joints and places where different building materials meet. Give careful attention to the foundation, because that's a vulnerable area. Check beneath decks, porches, and crawl spaces. Don't forget the garage; barns; sheds; the places where they store garbage cans; dumpster areas; compost heaps; and piles of firewood, lumber, or junk.
Best Practices for Wildlife Control
- Assess the Situation
- Choose Management Options
- Tools and Techniques
- Preventing Problems
- Evaluating Success
Professionalism Resources for NWCOs
This manual was written as a guide to train nuisance wildlife control operators in New York State. Laws and regulations may differ in your state. Always consult local and state laws before implementing wildlife damage management activities.
We thank the New York State Department of Environmental Conservation for contributing this information.Produced by the NYS Department of Environmental Conservation, Cornell Cooperative Extension, and the NYS Integrated Pest Management Program.