Choose Management Options

Step two: Choose management options


Learning objectives for step two: choosing management options

  1. Describe the options for managing a wildlife conflict.
  2. Explain one way you’d make an area less attractive to nuisance wildlife by actually changing the environment, and one way you’d do this by changing people’s habits.
  3. List two of the factors that influence the effectiveness of repellents.
  4. Which management option would almost always be a part of your solution? Why?

At this point in our story, Sherlock would retreat to his apartment, pick up his pipe, and think. So many clues, so many possible solutions: how do you choose?

With a proper species identification, the information you learned during your interview and inspection, and your knowledge of that animal’s life history, you can estimate how many individuals might be present. Again, this will depend on the time of year (is it breeding, rearing young, hibernating, or migrating?), and the animal’s social habits. Woodchucks are generally solitary, while bats are social and are often found in colonies. Is this animal territorial? Will it drive away others at certain times of the year? Does it have a large home range? If so, it might not be able to meet all of its needs just on this site. That could be tricky, because that might mean that the best solution would include addressing a situation on someone else’s property, too, and you might not be able to do that.

All of this detective work is meant to help you decide how many individuals this site would naturally support. Of course, there could be other factors at work here, and you need to take that into account, too. If someone is feeding the wildlife you could encounter unbelievably high population levels, way beyond what the books suggest.

As you consider those questions, you may eliminate some control techniques because they’re not practical, safe, or discreet enough for this situation. Legal restrictions may eliminate some options. The presence of free-roaming pets, children, or protected wildlife might also lead you to favor some approaches and avoid others.

Six options when confronted with a nuisance wildlife damage situation

Okay, you’re ready to decide on a management strategy. We’ll discuss each major strategy now, and then, in step three, will describe the common techniques used to achieve that method. In some cases, there are many different ways to attempt to achieve a particular strategy. For example, we’ll describe more than a half-dozen ways to remove an animal from a site.

What are your options when confronted with a nuisance wildlife damage situation?

  1. Do nothing. Let the problem resolve itself.
  2. Make the environment less attractive.
  3. Scare the nuisance animal away.
  4. Remove the culprit.
  5. Reduce the local breeding population.
  6. Keep the animal out (exclusion).

Regardless of which strategy you favor, keep these few points in mind. First, a combination of techniques almost always works better than relying on one method. Be as selective and discreet as you possibly can. Proper timing will increase your success rate (you wouldn’t try to trap a nocturnal animal during the day, would you?) Take advantage of the species’ vulnerabilities and habits, too. And watch out for risky conditions.

Option: Do nothing.
Let the problem resolve itself.

Techniques: Education and persuasion.

Talk to your customers, so they understand why this problem developed and what’s likely to happen next. The best thing to do may be—nothing.

For example, American robins may attack windowpanes for a few weeks during the early spring, as they establish their nesting territories. The birds attack their reflection in the glass, because they mistake it for an intruder who’s threatening their territory. But they’ll stop soon. Many people will be satisfied to wait it out, once they realize the problem will go away on its own. If someone can’t tolerate the noise, you can use your knowledge of animal behavior to suggest an easy fix: cover the window to reduce the reflection. If the robin doesn’t see the “intruder” (which is just its own reflection) then it won’t have a reason to defend its territory. (Quite a few problems with migratory birds take care of themselves within a few weeks.)

We all have our moments. It’s easy enough to work yourself into a bit of a frenzy over something that’s not such a big deal, or not even true. For example, many people believe “drooling = rabid animal.” Yet healthy opossums drool and shake as part of their defensive behavior, and this species doesn’t often catch rabies. In such a case, sharing correct information may make a “problem” disappear.

If someone doesn’t know much about wildlife, how can they evaluate the situation sensibly? They lack information and the context for understanding it correctly, which you can provide. Perhaps you can handle this over the phone and save yourself the trip.

There are many times when this “Zen” approach is common sense. As soon as the snow melts, you’ll probably get calls from people concerned about moles or voles ruining their lawns. There may be tunnels all over the place! But there’s a good chance that this clue is all that’s left. Both moles and voles change their habits seasonally. These tunnels are the sign of their winter activity. They may have left the area. It’s much more sensible to wait a little while to see if there’s evidence of new damage.

Sometimes, by the time you’ve arrived, the problem is fixed. Maybe a bat entered a room through a torn screen and has already escaped. You may only need to explain the cause of the problem and how to prevent repeats of this scenario. Consider creating a short tip sheet to explain the predictable problems. This could save time on the job. Instead of your long explanation, hit the high points and leave the customer with the written details.

Option: Make the environment less attractive to the culprit.

Techniques: Remove food sources; keep buildings in good repair; protect vulnerable areas with barriers; maintain a tidy landscape; move livestock to protected areas; switch to landscape plants that the nuisance animals find less tasty.

What do most wildlife seek when they invade our spaces? Food and shelter, especially safe places to raise their young. They may also be enticed by water and places to just hang out or loaf.

If you can remove those enticements or change them so they’re not as appealing as they were before, you may be able to solve the problem for good. This approach is known as “habitat modification.” Although it’s sometimes more expensive up front, the long-term payoff is usually good because this gets at the root of the problem. Sure, you can just trap and remove an animal. Year after year after year… that adds up.

There are scientists and NWCOs who believe that some animals, such as raccoons, learn to recognize a good deal. Once a nuisance, always a nuisance, they say. It’s even possible that the young of a female who has such habits learn to take advantage of the riches we provide because of their experiences with their mother. If true, then the quick-fix approach could be even more costly than we imagine.

People unintentionally feed wildlife. Spilled bird seed, pet food left in dishes outdoors, and garbage can become buffets for a variety of wildlife from rodents, bears, foxes, raccoons, to skunks.
People unintentionally feed wildlife. Spilled bird seed, pet food left in dishes outdoors, and garbage can become buffets for a variety of wildlife from rodents, bears, foxes, raccoons, to skunks.
When people intentionally feed wildlife, they can cause or worsen other problems.
The gulls shown in the parking lot may well mob people who try to feed them. Their droppings may foul cars.
The gulls shown in the parking lot may well mob people who try to feed them. Their droppings may foul cars.

Some of the most profound ways to modify a habitat may only involve persuading people to change their habits. For example, here’s a no-brainer for customers annoyed by bears that raid the bird feeder during the late spring and summer: don’t feed the birds during those seasons! Feed birds only during the winter, problem solved.

More examples: raccoons tipping over the garbage cans and making a mess? Store the cans in a protected area. Or hang the cans on a hook above ground so they can’t be tipped over (make sure the coons can’t climb up the pole or wall to reach the garbage can). If possible, put the trash out right before it’s due to be collected. Has the compost heap turned into a restaurant for skunks, opossums, rats, and raccoons? Install an animal-proof compost bin (For information, consult Cooperative Extension’s “Master Gardener” program). You’ll find a host of suggestions in each of the species accounts.

Many wildlife species prefer to use the same path to food, shelter, water, and loafing areas. Can you block that route, or make it unpleasant? Canada geese, for example, love mowed grass. Let the grass bordering the pond grow longer to discourage the geese from using the site. Eliminate ponds from malls and business parks, and you can really make them miserable. This general idea works for many species. If a tree branch overhangs a roof, trim it 8–10 ft. away, and the most acrobatic squirrel won’t be able to make the leap anymore.

Other ways to change the conditions of the habitat may require efforts on a grander scale. Take a few tips from farmers, who combat pests by tilling, rotating crops, controlling water levels, and heating up the soil. Can you change the temperature, water level, or amount of light that reaches an area? Bats like warm, dark places. If they’re roosting behind shutters, put a block between the shutter and the siding. This holds the shutters further away from the wall and exposes the bats to drafts and more light. That might convince them to move on.

If wildlife dine on flowers and shrubs, consider switching to plant varieties that they don’t find as tasty. For a list of plants that are more resistant to deer, see the Cornell fact sheet, Resistance of Woody Ornamental Plants to Deer Damage (citation in resource section).

Option: Scare the nuisance animal away.

Techniques: Use of visual repellents (strobe lights; lasers; mylar tape; balloons); use of noisemakers; (distress and alarm calls; pyrotechnics; sirens) ; hazing (with predators or radio-controlled craft); Use of guard animals. NWCOs with a commercial pesticide applicator license can also use a variety of chemical repellents.

“Run ’em out of town.” That’s the idea of this method. But it’s easier said than done. To make this work, think like the animal. What scares it? If you rely on something the animal doesn’t experience in nature, the technique may not work because it’s not meaningful to the animal. (An envelope from the IRS may send some people into hiding but it wouldn’t faze starlings. Now that’s obvious, but many frightening devices fail for just this reason. They don’t make any sense to the species they’re supposed to scare.)

Repellents are objects, substances, or techniques that repel, or drive an animal away. There are several kinds: scare devices; chemical repellents (which can only be used by NWCOs with a commercial pesticide applicator license); and guard animals.

Repellents either frighten the animal away or make the desired object, such as a crop or nesting site, intolerable by making it smell or taste nasty, or feel bad to the touch. Animals may be “hazed,” or driven away from a site, when chased by predators (dogs, falcons) or vehicles (radio-controlled planes, boats).

See the mothballs to the left of the rocks? Not exactly repelling the skunks, are they? Repellents often work better when several are used together, in an unpredictable fashion. They're generally better at preventing a new behavior than stopping a well-established habit.

See the mothballs to the left of the rocks? Not exactly repelling the skunks, are they? Repellents often work better when several are used together, in an unpredictable fashion. They’re generally better at preventing a new behavior than stopping a well-established habit.

Many repellents are meant to frighten the wildlife away. These include scary-looking objects, such as mylar tape, strobe lights, models of predators, and “scare-eye” balloons; noisemakers, such as propane cannons, bangers, clappers, crackers, and distress calls; devices that combine lights and noise to scare animals; and the use of guard animals, such as dogs, that chase wildlife.

Sometimes, frightening techniques fail for a very basic reason: the animal can’t hear or see the thing that’s supposed to scare it. Oops. This is why ultrasonic devices don’t work on birds. They can’t hear them.

Again, to avoid this mistake, think like the animal. Which senses does it rely on most: smell, sight, hearing, taste, or touch? How do individuals warn each other of danger? Beavers noisily slap their tails while deer flash theirs, a quiet but highly visible warning. Birds often rely on sight and sound to detect danger, while mammals rely more heavily on odor cues.

Another biological factor that influences the effectiveness of some repellents is the nervous system. Birds and mammals are wired a little differently so they perceive the world differently. Capsaicin, the active ingredient in hot peppers, burns the mouth, eyes, and nose of mammals. Hot hot hot! Not so for birds. They are insensitive to capsaicin, so they ignore it. On the other hand, birds find methyl anthranilate, a sweet grape flavoring, highly irritating.

Distress and alarm calls, hazing with live predators, and objects that mimic the animal’s real predators, are often more effective than many other frightening devices because they make more sense to wildlife. Animals naturally fear predators, for good reason. Given time, many animals learn that other scary objects actually pose no danger to them, so they ignore them. That’s why these devices are often useful for only a short time.

Chemicals are used to repel wildlife, too. But unless you also have a commercial pesticide applicator license, you can’t use them in your NWCO business. Chemical repellents are classified as pesticides. If you do have this license, remember to check each product to make sure it’s registered in the state, and for use on that species, and in the way you’d like to apply it. Read the label carefully, because the label is the law.

A variety of commercial chemical repellents are available especially to reduce mammal browsing in orchards and vineyards, and on nursery stock and ornamental plants. Most products are registered for deer and rabbit control on non-food crops and ornamentals. (For more information, contact your regional DEC office and speak to Bureau of Pesticides staff). Quite a few home remedies, such as soap and baking soda, have repellent properties. Likewise, concoctions made from plant extracts such as mint, citrus peel, or marigolds may act as repellents as well as pesticides. But home remedies are out-of-bounds for NWCOs; they are not legally registered products.

Repellents can be a valuable addition to your strategy. This nonlethal technique saves you the trouble of capturing or handling wildlife—when it works. Your best chances are to try them when these three things are true: there’s only light to moderate damage; the site is small; and a few applications should provide adequate control.

Option: Remove the culprit.

Nonlethal techniques: Direct capture; use of live traps, one-way doors, or repellents.

Lethal techniques: Use of lethal traps; shooting.

NWCOs with a commercial pesticide applicator license may also use a variety of pesticides.

Note: Once the animal is captured, it may be released; transferred to a wildlife rehabilitator (if it’s injured or orphaned); or killed. In addition to the techniques mentioned above, there are other appropriate methods for killing wildlife, such as the use of a carbon dioxide chamber, which are described later in this chapter. These techniques and tools do not aid in the capture or removal of that animal from the site so they’re not listed above.

There are several methods for removing animals from areas in which they are unwanted. Nonlethal techniques include direct capture using a hand-held device or net, and the use of one-way doors or live traps. Lethal methods usually involve lethal traps, shooting, or pesticides. Obviously, some techniques are better suited for some animals than others. With all of these methods, be aware of the possible presence of young so you don’t create wildlife orphans.

Whether you’ve chosen a nonlethal or lethal removal technique, you’ll be faced with the same question: What will you do once you’ve caught the animal(s)? In chapter two, we suggested that one of the major questions NWCOs should consider is the possible ecological consequences of each method. You have three basic choices once you’ve captured an animal: you can release it on site; you can transfer it to a new place, or in some cases, to a wildlife rehabilitator or licensed facility; or you can kill it.

Trap and On-site release

Releasing the animal on site generally causes the least stress to the animal. It may be a best practice for your customer’s situation, but it requires some consideration. For example, if the animal is obviously sick or may have exposed someone to rabies, stop right here. In those cases, releasing the animal would be risky (and possibly illegal).

Before you release an animal, consider the possible effects on the animal, your customer, your customer’s neighbors, and local wildlife populations. Unfortunately, this hasn’t been well-researched yet and as you’d expect, it’s a hotly debated point. Is it ethical to potentially pass your problem on to the neighbors? Is it humane to release an animal if its survival chances aren’t good?

In this condominium complex, raccoons moved from one cupola to the next. Notice the bent louvers.
In this condominium complex, raccoons moved from one cupola to the next. Notice the bent louvers.

Here are a few guidelines that may help you resolve this point as we wait for solid evidence. First, consider which species caused the problem. Bats and snakes cannot create openings in buildings. Remove them, then repair the hole that let them in, and they’re not likely to trouble your customer again. They can’t force their way into the neighbor’s building, either. So on-site release is almost always appropriate with these species. In fact, it’s actually preferred. Both bats and snakes congregate, which means that the individuals at that one site may represent a good percentage of the local population. What you do at this site could have broader effects than it would if you were dealing with a species whose population is more dispersed. (Please read the bat account for some additional factors to consider when dealing with large colonies.)

Now, let’s apply the same logic to the great chewers: mice, rats, squirrels, raccoons. They can most definitely chew their way back into the building. If the nuisance animal has developed the habit of using a building it may become a repeat offender, especially if den sites are rare, or the animal is ready to give birth and needs a den right away. The ethics of this situation are less clear.

Look around the neighborhood. If the nearest building is miles away, then the risk of the animal troubling the neighbors could be low. If it’s a condo complex of attached buildings which all share the same deficiency that allowed the animal to gain access, such as poorly designed louvers, it’s much more of a concern.

There are two circumstances in which on-site release is almost a no-brainer: the accidental capture, and the accidental entry. Say you’re trying to catch a skunk but you find an opossum in your cage trap instead. Open the door and let it out. It’s not causing any damage; it’s not a nuisance; it’s just in the wrong place at the wrong time. Likewise, animals sometimes end up inside buildings accidentally. Birds and squirrels sometimes fall down chimneys. Bats will sometimes enter a building through an open window or door. If the animal poses little risk to nearby people, you should be able to capture it and release it outdoors. Help your customers understand how to prevent another animal from dropping by (maybe you’d offer to install a chimney cap, for example). Done. Everybody happy.

On-site release, especially if coupled with effective exclusion that will prevent the animal from re-entering the building, may be a good solution for your customer’s problem. Use your professional judgment.

“Trap and transfer” (a.k.a. “relocation”)

If an animal is sick or injured, a NWCO may be able to transfer the animal to a wildlife rehabilitator. Even NWCOs who are very careful to avoid orphaning young animals may sometimes find themselves with a litter that’s been separated from its mother. Wildlife rehabilitators may be able to help. Of course, it’s better to have a good relationship with your local rehabber before you need that person’s services. To find licensed rehabbers who work in your area, contact your regional DEC wildlife staff or New York’s association of rehabbers, the Wildlife Rehabilitation Council, or check their website.

In most cases, when people refer to “trap and transfer,” they don’t mean turning the animal over to a rehabber, they mean moving the animal to a new place. This is a common but controversial technique. While solving some of the problems associated with releasing the animal on-site, it raises other concerns.

Let’s try our six best practices questions from chapter two on this technique.

  1. Is it safe?

Reasonably so. Trap and transfer involves transporting the animal, which is stressful, so the animal may be quite agitated when you’re ready to let it out.

  1. What are the likely ecological consequences of this action?

Can spread diseases through wildlife populations.

An area can only support so many individuals of a particular species. Raising the level of competition for food, shelter, and den sites (at the release site) could hurt more animals in the long run.

  1. Is it practical?

At best, we can say “effectiveness unknown for nuisance species.”

If the customer opted for capture and relocation without exclusion, chances are good that the problem will happen again. A new animal will usually quickly replace the one that was removed.

The relocated animal may return to the site. Many animals have strong homing instincts. A male raccoon, for example, can travel as much as 5–10 miles each night. Bats routinely travel hundreds of miles to their hibernacula.

Is there a suitable release site close by?

Can you afford to make the time to take the animals to the site?

You’d need to secure the permission of the people who own the land that you’d like to use as a release site. On public land, you’d need the permission of the land manager. Can you get permission in time? What if you’re refused?

  1. Is it humane?

How well does this species respond to transport? Will the animal be so stressed by the process that it’s unlikely to survive, anyway? Studies have shown that the stress and trauma of capture causes some animals to die a few weeks later.

What are its chances of finding a new territory? The animals that are already established in the release site may drive off or attack this animal. Between the capture, transport, and release in a foreign locale, this animal is probably already stressed. Does it stand a chance?

What are its chances of finding food? During the winter, when food is scarce for many of these species, placing an animal in an unfamiliar place can cause it to slowly starve to death. This is especially true if that animal would normally rely on stored food to make it through the winter, as squirrels do.

Add to the troubles: what if this is a mother with young? Would she simply abandon or kill her young because she’s already been too stressed? If not, will she have time to find food, shelter, and a safe place to raise her young?

Some animals are killed by cars, dogs, or other predators as they try to return to their original homes through unfamiliar territory.

  1. Is it legal?

This technique is legal for NWCOs (assuming, of course, that they have the permission of the owners of the release site), but not for the general public. Many people don’t realize that.

Is the animal classified as a “threatened” or “endangered” species, either on a statewide or national basis? If so, stop! You cannot handle it in New York State. Do not harm it or its habitat.

Pigeons wearing leg bands are also out-of-bounds for NWCOs in New York.

Are you dealing with a migratory bird? Nearly all are protected by the Migratory Bird Treaty Act. You’d need federal and state permits, which would spell out approved techniques. Follow your permits.

Is the animal classified as an “unprotected” or “protected” species in New York State? If it’s a protected species, refer to the Environmental Conservation Law, which describe the situations in which you can “take” (or kill) that species. That information is included in the species accounts in the appendices.

Goose roundups are an example of a special culling operation. They’re most effective when the geese are molting and can’t fly. If the birds are on the water, people in boats drive them onto the land. Then others walk behind the geese to direct them towards the pen.
These temporary enclosures usually have a funnel-shaped entrance that guides the birds outside.
These temporary enclosures usually have a funnel-shaped entrance that guides the birds outside.

You are talking about wildlife, right? Because your NWCO license does not give you the authority to handle feral cats or dogs, or livestock, such as domestic ducks. Those species are covered by other laws.

Once you’ve established that you can legally take that species, check local laws. The use of some tools such as “dart guns” may be restricted in some areas.

During times of disease epidemics, there may be restrictions on moving animals. You still have to follow DEC and Department of Health guidelines.

  1. How would your actions play on the evening news?

This is hard to predict. So far, there haven’t been enough scientific studies to answer some of the important ecological questions raised by this approach. We can’t say whether this is likely to be a “happily ever after” story for the relocated animal, or a tear-jerker. How will people who live near the release site feel?

Is relocation all bad? (If it was, would it be in this manual? Really.) Wildlife biologists relocate animals. This technique has been used to reintroduce wildlife into areas where they were once found, for example, or to stock certain areas with game species, such as wild turkey. But when it comes to nuisance wildlife, the usefulness of this technique is debatable. Your customers may request this option, so you’ll need to think about it.

Should you decide to relocate an animal, there are several things you can do to give it the best possible chance of survival. Find an area with suitable habitat for that species, with good and varied sources of food and shelter. Release the animal during the time of day when it’s naturally active, for example, release a nocturnal animal at dusk or in the evening, not in the middle of the day. Keep families together and release them into a covered area, such as a culvert or hollow log; this will increase the chances that the mother will stay with her young. Follow the guidelines for preventing orphaning (see step three). And don’t overload an area.

Killing the captured animal

You may choose to avoid relocating animals by refusing to offer that service, but as a NWCO, if you handle mammals, you must be prepared to kill wildlife, in case a rabies test is needed. You are legally required to follow the directions of the DEC and the Department of Health. Most people understand and support measures taken to protect public health and safety. What about other circumstances?

Like relocation, this technique is also controversial. Here’s how it stacks up as a best practice.

Is it safe?

Care and skill are required when using a lethal technique, even one that’s commonly used by the general public, such as setting a mouse trap. Consider the risks to people—including yourself—and those to other wildlife, pets, and livestock. The risks vary depending on the technique. For example, a carbon dioxide chamber doesn’t pose a risk to other species because you control which animal is placed inside it. Killing methods are described later in this chapter, with details about safety.

What are the likely ecological consequences of this action?

Most of the species described in this manual are thriving in New York. Their populations are rising, which is one of the reasons why they’re more likely to come into conflict with people. In most cases, you would be removing a small number of animals and wouldn’t significantly affect local populations. However, if you’re faced with a large bat colony or a snake hibernacula, this is an important concern. In those cases, if possible, choose a combination of nonlethal methods.

Some lethal tools, such as pesticides and lethal traps, may pose risks to other species. That’s why they must be used carefully and are not appropriate in all cases. For example, if there are endangered or threatened species in the area that might be accidentally captured, a nonlethal capture method may be better. Yet, some lethal methods are so selective that they wouldn’t threaten some endangered species. For example, some snap-back traps don’t pose a threat to bald eagles. Consider the circumstances.

Is it practical?

If you’ve correctly diagnosed the situation, killing the nuisance animals will stop the problem—at least for a while. If the customer opted for removal without exclusion, chances are good that a new animal will take advantage of the situation. On the other hand, if the customer opts for removal using lethal techniques and exclusion, then you’ve provided a long-term solution without the risk of passing the problem on.

Is it humane?

This is an important topic that will be discussed in much greater detail later in this chapter. In each species account, we’ve described preferred and acceptable killing methods for that species. Use a preferred method whenever you can. You must match the technique to the species. For example, the use of a carbon dioxide chamber is not recommended for beaver, diving birds, or reptiles, because those animals can hold their breaths for a long time, so that method wouldn’t kill them quickly enough.

Is it legal?

Can you legally take that species? (Points 2–6 under the “is it legal?” discussion for trap and transfer also apply to the use of lethal techniques. Those points describe species that you cannot take.)

Check local laws. Some lethal techniques, such as shooting, for example, may be restricted in some areas.

How would your actions play on the evening news?

Think about this question long and hard—especially when you’re using lethal techniques. The best practices approach provides a solid framework for making decisions about nuisance wildlife situations. Don’t just give it lip service. Think before you act. Imagine that video camera is recording at all times. (Smile.)

Be sensitive and savvy. Work in private. Some of the killing methods described in this manual look gentler than others. If you have to kill an animal in front of observers—which you should avoid doing whenever possible—take a moment to explain what you’re about to do, and why you’ve chosen this method for this species in this situation.

Option: Reduce the local breeding population.

Techniques: Regulated hunting and trapping seasons; and special culling operations (permits may be needed).

Note: Some communities currently participate in research programs to test wildlife birth-control and sterilization techniques. These techniques are not yet proven, nor are they commercially available.

With most of the species handled by NWCOs, the focus is on an individual problem that generally affects a small area, such as one person’s home. Some species, such as Canada geese and white-tailed deer, may cause problems for an entire community. In this case, one aspect of the solution may involve reducing a breeding population. This is often done through regulated hunting and trapping seasons or special culling operations of adults, eggs, or young. Such efforts are usually planned by wildlife biologists, but some NWCOs participate in the project, so we’ll give you an overview of the method.

These approaches can be biologically, socially, and legally complex. They require community support and government oversight, and are usually beyond the normal scope of NWCO activity. The group in charge of this major effort may hire NWCOs to provide specific services, such as addling eggs.

Scientists are experimenting with birth control techniques for wildlife. This hasn’t yet proved generally effective for controlling populations, but contraceptive and sterilization methods are being tested in a wide number of species on a small scale. (To learn more: Fagerstone, K.A., M.A. Coffey, P.D. Curtis, R.A. Dolbeer, G.J. Killian, L.A. Miller, and L.M. Wilmot. 2002. Wildlife fertility control. Wildlife Society Technical Review 02-2, 29pp.)

The bottom line for the average NWCO: you may not even want to get involved in special culling operations, but you can encourage landowners to allow hunting and trapping on their land, especially if they’re dealing with nuisance wildlife. This may be one of the most effective ways to solve problems with beaver, muskrat, raccoons, squirrels, and deer, for example.

Option: Keep the animal out of the area (exclusion)

Techniques: Repair buildings to seal entry holes; protect vents, louvers, and sewer pipe vents with animal-proof designs or add screens or shields; cap chimneys; fence outdoor areas; use netting, spikes, electric shock devices, or plastic strips to keep birds away from alcoves, ledges, and other perches; erect “post-and-wire” grids over large areas to discourage birds from landing there. For more information, see step four.

There’s one strategy that should almost always be used as part of your solution: exclusion. In some cases, you may be able to solve the wildlife conflict by putting up a barrier that keeps the animal away from the vulnerable area, whether it’s a garden, child’s sandbox, orchard, or the foundation of a building.

Exclusion is one of the best ways to prevent nuisance wildlife conflicts. It can stop repeats of the problem, and may even prevent other conflicts from ever happening. And it will probably increase the effectiveness of other strategies, such as habitat modification, the use of repellents, and the removal of the nuisance animals.

When you can, persuade your customers to take advantage of your wildlife expertise and knowledge of building construction by hiring you to make their properties “animal-proof.” Perhaps you only want to make recommendations, or maybe you’re happy to do the actual repairs. In either case, you probably know more about which exclusion products to use and how to install them correctly than the average building contractor.

There are many exclusion products on the market. Top: A chimney cover will keep many animals, such as birds, bats, squirrels, and raccoons from getting into a chimney. Middle: This net is hung over a pond or field to discourage birds from landing in the area. Bottom: Here’s an example of an exclusion device that most NWCOs custom-fit to the site. It’s called a “rat wall.” This “L”-shaped fence can be installed as a free-standing barrier or attached to a porch, shed, or stairs, as it is here. The bottom is bent into a shelf that keeps animals from digging underneath it. In this photo, you can see the bottom, but not the top, which is attached to the concrete. Once it’s covered with soil, it won’t be noticeable at all.





Higher, deeper, further…optional activities to explore other perspectives about this topic

  1. Survey your NWCO friends to find out which management strategies they use most often. Are they happy, or do they wish they could change things?
  2. Find out if any nearby communities are actively trying to control white-tailed deer or Canada geese. What’s happened so far? How is it working?
  3. Search the web for fact sheets that explain why some temporary wildlife conflicts happen (such as robins pecking at windowpanes, or woodpeckers drumming on gutters). Create a file to help you respond to customer questions.


Before you answer the review questions, you may wish to think about the learning objectives.

  1. Describe the options for managing a wildlife conflict.
  2. Explain one way you’d make an area less attractive to nuisance wildlife by actually changing the environment, and one way you’d do this by changing people’s habits.
  3. List two of the factors that influence the effectiveness of repellents.
  4. Which management option would almost always be a part of your solution? Why?

Review questions

The smudge on this wall and the slight depression in the ground where an animal has squeezed under the shed. It’s important to locate the animal’s travel routes and find the place where it enters the building. If you’re going to remove the animal, those are among the best places to set a trap. In many cases, when you’re done with the job, you’ll block that entry hole to make sure animals can’t get back into the building.

  1. To make an area less attractive to nuisance wildlife, you might persuade your customers to:
  2. keep the area around the bird feeder clean
  3. remove dog feces from the yard every day
  4. store the trash cans in the garage, then put them out right before the trash pick-up
  5. all of the above
  6. To make a park less enticing to Canada geese, you advise the city officials to:
  7. pave over the grass
  8. hold firework displays every night at 8 p.m.
  9. let the grass around the pond grow taller
  10. release wolves
  11. In nearly every job, you’d expect to do this, or might advise your customers to take care of it. What is it?
  12. clean up the area with antibacterial soap
  13. tell the neighbors they’ll be next. But if they hire you now, there’s a 10% discount
  14. nothing
  15. exclusion, to prevent problems
  16. Your customer tried a bird scare device, but it didn’t work. He wants to know why. You explain (choose all possible reasons):

___ birds can’t hear ultrasonic sounds

___ the birds get used to seeing it there, so it’s not scary anymore

___ you played the alarm call of a crow, but those are starlings roosting in your tree.

___ your border collie is a wuss. When I drove up, the Canada geese were chasing your dog!

___ scare devices never work

  1. Your customer wants to consider every option for solving his wildlife problem. You say:
  2. Well, there are several approaches. I could trap it, or try to scare it off, or put down some pesticides. That’s about it. Trust me, let me trap the animal and take care of it for you. If we use pesticides, the squirrels could die in the walls, and that would stink so bad you’d be sorry you did it. You don’t have to see a thing. But I don’t have the time to talk all day.
  3. That’s a trade secret. Don’t you have to go to work, or something?
  4. It mostly comes down to capturing the animal. We can live trap the animal, or use a lethal trap. If I see the animal, I might be able to catch it using my catchpole. I’d probably set this cage trap. Do you want to release the squirrels alive, or do you want me to take care of them? Because if you let them out, they might just get back in, so then it’s important to fix all the holes to prevent that.
  5. Some wildlife problems stop after a short time, so you don’t have to do anything. That’s not true here. I suggest we use a combination of approaches. We make the place less cozy for the squirrels, while I work on removing them. You can try to scare them away. When we’re done, we fix all the holes so they can’t get back inside.


  1. d
  2. c
  3. d (remember, most wildlife diseases that are common in the Northeast are not caused by bacteria, so an antibacterial soap isn’t going to help that much. Choose a disinfectant, such as dilute bleach, instead.)
  4. The only answer that’s flat-out wrong is the one that suggests that scare devices and repellent techniques never work. It’s unlikely that a border collie would be afraid of geese. This is one of the best breeds of dog to choose for hazing geese.
  5. d
Shed smudge
The smudge marks on this wall and the slight depression in the ground show where an animal has squeezed under the shed. It’s important to locate the animal’s travel routes and find the place where it enters the building. If you’re going to remove the animal, those are among the best places to set a trap. In many cases, when you’re done with the job, you’ll block that entry hole to make sure animals can’t get back into the building.