Wildlife Damage Inspection
A site inspection is a wildlife damage inspection. The problem may be chewed wires, a hole in the wall or ceiling, torn and shredded insulation, or perhaps tunnels in the lawn, damaged plants, or dead chickens or livestock. Damage identification is critical to species identification and to resolving the wildlife damage conflict.
A thorough site inspection is the foundation of an effective approach to control and mitigate wildlife damage. This section focuses on structural site inspection. Farm animal predation and crop damage inspections require similar investigative skills. Take the time to investigate every wildlife damage complaint thoroughly to avoid future problems.
The first thing to do is find the source of the problem. You need to understand the type and extent of the damage and you must identify the problem animal in order to create a solution. Look for clues that will help you figure out what attracted the problem animal(s) to the site. Remember the two key habitat enticements for wildlife – food and shelter.
Signs of Wildlife Presence
Use your knowledge of animal behavior. Wild animals usually provide many 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.
Visual sighting. This is one of the easiest ways to identify the species, if you can trust the observer. If nocturnal animals frequently are seen during the day, the animal may have young and is feeding more often, or the local population is high, especially with rats and mice. If dealing with a bat colony, you may have a hard time locating the entry holes. Stand outdoors at dusk or dawn, and watch where the bats enter or leave the building. There’s the hole! A more detailed description of how to conduct a bat watch is in the Bat species section of this manual.
Sounds. Listen for various squeaks, growls, cries, hisses, chitters, and 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, 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 also can be identified by their odor. Dens of other animals, including raccoons, have their own scent.
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 often soft, while old ones are dry, lighter in color, and hard. Old droppings crumble easily.
Urine. You can see rodent urine using an ultraviolet light — urine glows blue-white. Unfortunately, other materials also glow, which can be confusing until you become familiar with the typical background fluorescence of a home or office. In regular lighting, you may notice discoloration on building materials in attics or crawl spaces. It is 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. Nests and food caches sometimes can be found when cleaning garages, attics, basements, closets, and other storage places. Rats, squirrels, and other rodents often store food in attics.
Entry sites. The location, size, and condition of the entry sites, such as holes, cracks, and loose siding are important clues to the species involved.
Burrows. Woodchucks, chipmunks, moles, voles, and Norway rats can dig burrows. 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.” Sometimes you can 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, often you can find rabbit fur, bones, and feathers near the den of a fox or coyote. If you can’t find sign of prey, then you’re probably dealing with an herbivore, such as a woodchuck.
Runs. Look for smooth or worn trails 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 often are seen in the animal’s run where it rubs against a surface during its travels, leaving behind dirt and oil from its fur. Look on pipes, beams, walls, and the outside edges of holes.
Tracks and claw marks. Footprints, tail marks, and wing prints may be found in dusty surfaces, sand, soft soil, and snow. If the surface doesn’t show tracks well, you can sprinkle nontoxic tracking dust (such as chalk powder or unscented talc) in a likely area, and return later to look for 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 have 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 these signs. To improve your identification skills, consider making hair sample charts. Clip a tuft of hair from an animal you’ve dispatched, and attach it to the chart with the appropriate label.
Gnawing. Look for evidence of chewing (wood chips, tooth marks, holes, shredded fabrics, frayed wires). Some wildlife will gnaw to enlarge a crack or enter a space. Wood chips may be seen near baseboards, doors, basement windows, kitchen cabinets, furniture, and stored materials. You could find shredded clothing, or see tooth marks on pipes. Rodents and raccoons often chew on the insulation around wires. The size of the tooth marks will help you tell whether you’re dealing with mice, rats, or squirrels.
Pets become excited. When cats or dogs hear or smell rodents in a wall or other inaccessible space, they may become very interested and whine, sniff, or scratch at the spot.
Access routes. Walk around outside and try to imagine the route the animal might have used to gain entrance to a building. Are trees or utility lines near the roof? Could the animal 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.
Fence lines. Walk the fence lines and look for damage or openings in the fence that can allow animals to enter. Sometimes trees can create access routes for animals. Check to make certain the fence go all the way to the ground and that there are not depressions under the fence that allow small animals to pass.
Where is the problem occurring?
What signs of wildlife are present?
Inspecting Specific Wildlife Signs
Inspection Techniques & Strategies
- Paper plug test – Use this test so you don’t trap animals inside a hole, or your house.
- How to Observe – Clues help identify the animal causing the problems.
- Thermal Imaging – Population Studies–Tennessee State Wildlife Dept.