Population Biology Commons^™

Prairie Dogs, Gary Witmer, Jon Grant, Kendra Cross

Wildlife Damage Management Technical Series

Prairie dogs (Cynomys spp.) occur throughout the prairie states of middle North America from Mexico northward into Canada. They occupy a variety of habitats from prairies to high mountain valleys and sage brush-dominated deserts. The most common species is the black-tailed prairie dog (Cynomys ludovicianus; Figure 1). Prairie dogs are considered a “keystone species.” They provide habitat for many other native, grassland species. Prairie dogs live in colonies or “towns” that can span hundreds to thousands of acres. Depending on the species, their presence is evident by their burrow system. Despite the many ecosystem benefits prairie dogs provide by modifying …

Free-Ranging And Feral Cats, Alex Dutcher, Kyle Pias, Grant Sizemore, Stephen M. Vantassel

Wildlife Damage Management Technical Series

Domestic cats (Felis catus) are a common household pet in the United States, with an estimated 25.4% of households owning cats (American Veterinary Medical Association 2018). While an increasing number of cat owners keep their pet cats exclusively indoors, a portion of society maintains that domestic cats are entitled to a free-ranging lifestyle and may even consider unowned domestic cats to be wildlife. Although wildlife managers recognize the beliefs of many concerned stakeholders, including advocates who use strong emotional appeals on behalf of cats, it remains that free-ranging and feral domestic cats are an invasive species spread by humans (Lowe …

Gray Wolves, Eric Gese, John P. Hart, Patricia Terletzky

Wildlife Damage Management Technical Series

Wolf conflicts are primarily related to predation on livestock, pets and other domestic animals, as well as their direct and indirect impacts on native ungulates (i.e., big game). Economic losses vary widely with some livestock producers facing high levels of depredation in some areas. This publication focuses on wolf ecology, damage, and management, particularly as it relates to wolf depredation on livestock and other conflicts with people.

Wolves and people share the same environments more than people realize. In the U.S., wolves are not confined to wilderness areas. Though curious, wolves generally fear people and rarely pose a threat to …

Monitoring For Wolves, Jeff Hansen, Cat Urbigkit

Wildlife Damage Management Technical Series

Gray wolves (Canis lupus) and Mexican wolves (Canis lupus baileyi) once again roam across landscapes where they have been absent for decades (Figure 1). With wolf range expansion comes increased opportunities for conflicts when wolves harass or prey on domestic livestock or other animals. Wolves have relatively high reproductive and dispersal rates but detecting individual animals in low-density populations is difficult without a concerted monitoring effort. In fact, wolf presence in an area often is not known until there is a confirmed livestock depredation. Ranchers and wildlife damage management experts need not wait for livestock depredations to occur before wolves …

Coyotes, Rick Tischaefer

Wildlife Damage Management Technical Series

The coyote (Canis latrans; Figure 1) is a medium-sized member of the canid family. Once primarily found in western deserts and grasslands, coyotes have expanded their range across North America and into diverse habitats, including urban areas. This expansion occurred during a time of extensive habitat change and efforts by people to suppress coyote populations to prevent damage. Coyotes can cause a variety of conflicts related to agriculture, natural resources, property, and human health and safety. This document highlights a variety of methods for reducing those conflicts. Coyotes are a highly adaptable species and may become habituated to some management …

Feral Swine, Michael P. Glow, Nathan P. Snow, Kurt C. Vercauteren

Wildlife Damage Management Technical Series

Feral swine (Sus scrofa; Figure 1), also known as feral hogs, feral pigs, wild pigs, wild boar, or other similar derivations, are a non-native species considered to be one of the most destructive invasive terrestrial vertebrates in North America. While feral swine populations remained relatively small and confined in the continental United States following initial introductions by European explorers during the 15th century, substantial range expansion has occurred across every geographical region of the United States (Figure 2). This expansion has primarily been attributed to human-mediated movements, predominately for the purpose of establishing populations for recreational hunting, and facilitated by …

Grackles, Michael J. Bodenchuk, David L. Bergman

Wildlife Damage Management Technical Series

Numbering in the tens of millions of birds, grackle populations in North America can cause a variety of conflicts with people. Grackles eat agricultural crops and livestock feed, damage property, spread pathogens, and collide with aircraft. Their large roosts can be a nuisance in urban and suburban areas. A combination of dispersal techniques, exclusion, and lethal removal may help to reduce grackle damage.

Grackles adapt easily to human-dominated environments, and exploit human food and other features of human landscapes. Thus, an integrated damage management approach to grackle damage focuses on reducing and eliminating the damage, rather than simply controlling grackle …

Common Ravens, Luke W. Peebles, Jack O. Spencer Jr.

Wildlife Damage Management Technical Series

Damage Management Methods for Common Ravens

Type of Control -- Available Management Options

Exclusion -- Often ineffective or impractical

Fertility Control -- None available

Frightening Devices -- Effigies • Pyrotechnics and propane cannons • Lasers and flashing lights

Habitat Modification -- Bale and bury garbage • Install dumpsters with secure lids • Remove or bury dead livestock • Remove abandoned houses, sheds, and barns to eliminate nesting structures

Nest Treatment -- Allowed with proper Federal and State permits; Egg oiling or addling and nest destruction

Repellents -- Methiocarb (EPA Reg. No. 56228-33) • Methyl anthranilate (food-grade grape flavoring agent)

Shooting …

Black Bear, Jimmy D. Taylor, James P. Phillips

Wildlife Damage Management Technical Series

The American black bear (Ursus americanus, Figure 1) is a challenging species for wildlife agencies to manage due to its size, intelligence, extensive range, food habits, and adaptability, as well as societal views. In North America alone, agencies receive more than 40,000 complaints about black bear annually. Black bears are known as ‘food-driven’ animals, meaning most conflicts result from a bear’s drive to meet its nutritional needs. Not surprisingly, an overwhelming proportion of conflicts are related to their use of anthropogenic (human) food sources, such as garbage, bird food, and crops. Understanding what drives human-bear conflict is the first part …

Rose-Ringed Parakeets, Page E. Klug, William P. Bukoski, Aaron B. Shiels, Bryan M. Kluever, Shane R. Siers

Wildlife Damage Management Technical Series

Rose-ringed parakeets (Psittacula krameri; hereafter RRPA; Figure 1) are an invasive species in the United States, present in Alabama, Louisiana, Texas, and Virginia, and with established populations in California, Florida, and Hawaii. They are also the most successful species of invasive parakeet, worldwide. RRPA can cause significant damage to agriculture, including grains, oilseeds, fruits, and ornamental plants. Large flocks of RRPA roost near human infrastructure resulting in concerns about human health and safety (e.g., collisions with aircraft, disease transmission, feces accumulation, and noise complaints). The population growth and spread of RRPA is of conservation concern given the potential impact on …

Information Resources For Animal Control And Wildlife Damage Management, Stephen M. Vantassel, Michael W. Fall, Serge Lariviére

Wildlife Damage Management Technical Series

A bumper sticker reads, “If you think education is expensive, you oughta try ignorance.” That statement could not be truer in regard to wildlife damage management. Being willing to learn is a critical attitude for everyone involved in wildlife damage management. Since wildlife damage management intersects so many other disciplines, no single person can be an expert in all of them. In addition, the arrival of an invasive species, changes in building practices (e.g., egress windows, ridge vents), or the implementation of new regulations can confound traditional practices and require new control methods. Thus, it is important to provide a …

American White Pelicans, Tommy King

Wildlife Damage Management Technical Series

American white pelicans (Pelecanus erythrorhynchos, Figure 1) threaten aquaculture producers by direct predation and the spread of disease. They are also considered competition and a nuisance by some sports fishermen. Pelicans can also damage pond levees and crops, such as rice, by trampling the vegetation and depositing guano. A combination of wildlife damage management techniques is often necessary to reduce pelican damage to these resources. Aquaculture Prior to the winter of 1992, American white pelican depredations at catfish facilities in the Delta regions of Arkansas and Mississippi were limited, and birds were easily dispersed from the area. Since 1992, however, …

Safety, Stephen M. Vantassel, Brenda K. Osthus

Wildlife Damage Management Technical Series

Wildlife damage management (WDM) is an exciting field with many opportunities to provide solutions to the complex issues involved in human-wildlife interactions. In addition, WDM wildlife control operators (WCO) face a variety of threats to their physical well-being. Injuries can result from misused (Figure 1), faulty, or poorly maintained equipment, inexperience, mishandled wildlife, harsh weather, and dangerous situations, such as electrical lines. The goals of this publication are to: * Develop an awareness of safety issues and adopt a mindset of “Safety First”, * Review the major safety threats that WCOs face, * Provide basic information for WCOs to protect …

Wildlife Translocation, Michael T. Mengak

Wildlife Damage Management Technical Series

Many people enjoy wildlife. It enriches their lives in many ways. Nationwide, Americans spend over $144 billion annually on fishing, hunting, and wildlife-watching activities. However, wildlife is not always welcome in or near homes, buildings, or other property and can cause significant damage or health and safety issues (Figure 1). In one study, 42% of urban residents reported experiencing a wildlife problem during the previous year and more than half of them said their attempts to resolve the problem were unsuccessful. Many people who experience a wildlife conflict prefer to resolve the issue without harming the offending animal. Of the …

Wildlife Carcass Disposal, Stephen M. Vantassel, Mark A. King

Wildlife Damage Management Technical Series

Many wildlife management situations require the disposal of animal carcasses. These can include the lethal removal of wildlife to resolve damage or conflicts, as well as clean-up after mortalities caused by vehicle collisions, disease, oil spills (Figure 1) or other natural disasters. Carcasses must be disposed of properly to protect public sensitivities, the environment, and public health. Improper disposal of carcasses can result in public outrage, site contamination, injury to animals and people, and the attraction of other animals that may lead to wildlife damage issues. Concern over ground water contamination and disease transmission from improper carcass disposal has resulted …

Gulls, Martin S. Lowney, Scott F. Beckerman, Scott C. Barras, Thomas W. Seamans

Wildlife Damage Management Technical Series

Abundant gull (Figure 1) populations in North America have led to a variety of conflicts with people. Gulls cause damage at aquaculture facilities and other properties, and often collide with aircraft. Their use of structures on and near water results in excessive amounts of bird droppings on boats and docks. Their presence near outdoor dining establishments, swimming beaches, and recreational sites can lead to negative interactions with people. Large amounts of gull fecal material pollutes water and beaches resulting in drinking water contamination and swim bans. A combination of dispersal techniques, exclusion and limited lethal control may reduce damage to …

Mute Swans, David R. Marks

Wildlife Damage Management Technical Series

Mute swans (Cygnus olor) are an invasive species originally brought to the United States in the late 19th and early 20th centuries for ornamental ponds and lakes, zoos and aviculture collections. Original populations were located in northeastern states along the Hudson Valley but have since expanded to several Midwestern states and portions of the western U.S. and Canada. Mute swan damage includes competing with native waterfowl, destroying native plants, spreading disease, and colliding with aircraft. They are also considered a nuisance in some areas due to their abundant fecal droppings and aggressiveness towards people.

Mute swans can impact …

Muskrats, James E. Miller

Wildlife Damage Management Technical Series

The muskrat (Ondatra zibethicus) is a common, semi-aquatic rodent native to the United States (Figure 1). It spends its life in aquatic habitats and is well adapted for swimming.

Although muskrats are an important part of native ecosystems, their burrowing and foraging activities can damage agricultural crops, native marshes and water control systems, such as aquaculture and farm ponds and levees. Such damage can significantly impact agricultural crops like rice that rely on consistent water levels for growth.

Muskrats also cause damage by eating agricultural crops, other vegetation, and crayfish, mussels and other aquaculture products. Loss of vegetation …

Wild Turkeys, James E. Miller

Wildlife Damage Management Technical Series

Like other bird and mammal species whose populations have been restored through conservation efforts, wild turkeys (Figure 1) are treasured by many recreationists and outdoor enthusiasts. Wild turkeys have responded positively to wildlife habitat and population management. In some areas, however, their increased populations have led to increased damage to property and agricultural crops, and threats to human health and safety. Turkeys frequent agricultural fields, pastures, vineyards and orchards, as well as some urban and suburban neighborhoods. Because of this, they may cause damage or mistakenly be blamed for damage. Research has found that despite increases in turkey numbers and …

European Starlings, H. Jeffrey Homan, Ron J. Johnson, James R. Thiele, George M. Linz

Wildlife Damage Management Technical Series

European starlings (Sturnus vulgaris, Figure 1) are an invasive species in the United States. The first recorded release of the birds was in 1890 in New York City’s Central Park. Because starlings easily adapt to a variety of habitats, nest sites and food sources, the birds spread quickly across the country. Today, there are about 150 million starlings in North America. Conflicts between people and starlings occur mostly in agricultural settings. Conflicts can occur during winter in urban and suburban environments, especially in business districts.

Starlings damage apples, blueberries, cherries, figs, grapes, peaches, and strawberries. Besides causing direct losses from …

Herons And Egrets, Michael D. Hoy

Wildlife Damage Management Technical Series

Human-Wildlife Conflicts

Landscapes -- Herons and egrets commonly cause damage at aquaculture facilities and recreational fishing waters where fish are held at high densities. In one study, on average wading birds consumed from 4 to 24 golden shiners per day at minnow production facilities in Arkansas. Great blue herons and great egrets commonly feed at catfish production facilities in Mississippi. The tendency for herons and egrets to congregate in large feeding flocks often leads to extensive loss of fish at aquaculture facilities. Fish-eating birds also can have an impact on intensively managed sport fisheries. Damage occurs when herons and egrets …

Beavers, Jimmy D. Taylor, Greg K. Yarrow, James E. Miller

Wildlife Damage Management Technical Series

The American beaver (Castor canadensis) (Figure 1) is known as an “ecosystem engineer” because of the benefits their dams provide to biological diversity and ecosystem function. It also is considered a “keystone species” because of its ability to transform its environment, creating new habitats upon which other species depend. Despite the many positive benefits beavers provide through foraging and dam building, beavers also create conflict with people when their activities cause damage. The authors of this publication acknowledge and appreciate the many positive benefits that beavers provide; however, the focus of this publication is to provide basic information on beaver …

Sandhill And Whooping Cranes, Jeb Barzen, Ken Ballinger

Wildlife Damage Management Technical Series

As sandhill crane populations continue to grow in the United States, so too does crop damage, property damage to homeowners, and the risk of crane collisions with aircraft. Whooping crane populations also continue to grow, but with a global population of about 500 individuals (as of 2017), damage is rare and problems often require different solutions due to the species’ endangered status. The behavioral characteristics and habitat needs of sandhill and whooping cranes set the stage for conflict between these birds and people. Recognizing behavioral differences between territorial and non-territorial cranes greatly improves the effectiveness of any management effort.

Human-Wildlife …

Wildlife At Airports, Travis L. Devault, Bradley F. Blackwell, Jerrold L. Belant, Michael J. Begier

Wildlife Damage Management Technical Series

Collisions between aircraft and wildlife (wildlife strikes) are common occurrences across the developed world. Wildlife strikes are not only numerous, but also costly. Estimates suggest that wildlife strikes cost the civil aviation industry in the U.S. up to $625 million annually, and nearly 500 people have been killed in wildlife strikes worldwide. Most wildlife strikes occur in the airport environment: 72 percent of all strikes occur when the aircraft is ≤500 ft (152 m) above ground level, and 41 percent of strikes occur when the aircraft is on the ground during landing or takeoff. Thus, management efforts to reduce wildlife …

Monk Parakeets, Michael L. Avery, James R. Lindsay

Wildlife Damage Management Technical Series

Since their introduction to the United States in the 1960s, monk parakeets (Myiopsitta monachus) have thrived (Figure 1). Until recently, annual Christmas Bird Count data have shown the population to be increasing exponentially. In the U.S., monk parakeets are an urban and suburban species with few natural predators, diseases or other factors limiting their population growth. They exploit backyard bird feeders and non-native ornamental plants for food. Monk parakeets often construct nests on man-made structures, such as electric utility facilities and cell phone towers. Because the birds build and maintain nests throughout the year, management of parakeet populations …

Cedar Waxwings, Michael L. Avery, Anthony G. Duffiney

Wildlife Damage Management Technical Series

Prevention and control of cedar waxwing (Bombycilla cedrorum) damage to small fruits such as blueberry, cherry, and strawberry is vexing to growers in many parts of the United States. Cedar waxwings (Figure 1) travel in flocks and descend in large numbers on berry crops, especially during winter and migration. In short feeding bouts, waxwings eat, peck, or knock substantial amounts of fruit from the plants. These frugivores are difficult to discourage once they become established at a given location. Harassment early and often using pyrotechnics or other sudden noisemakers can help prevent flocks from being established. The most effective preventative …

Vultures, Michael L. Avery, Martin S. Lowney

Wildlife Damage Management Technical Series

Black and turkey vultures cause problems in several ways. The most common problems associated with vultures are structural damage, loss of aesthetic value and property use related to offensive odors and appearance, depredation to livestock and pets, and air traffic safety. Management of these diverse problems often can be addressed by targeting the source of the birds causing the problem, namely the roost where the birds spend the night. Often the roost itself is the problem, such as when birds roost on a communication tower and foul the equipment with their feces or when they roost in a residential area. …

Bird Dispersal Techniques, Thomas W. Seamans, Allen L. Gosser

Wildlife Damage Management Technical Series

Conflicts between humans and birds likely have existed since agricultural practices began. Paintings from ancient Greek, Egyptian, and Roman civilizations depict birds attacking crops. In Great Britain, recording of efforts at reducing bird damage began in the 1400s, with books on bird control written in the 1600s. Even so, the problem persists. Avian damage to crops remains an issue today, but we also are concerned with damage to homes, businesses, and aircraft, and the possibility of disease transmission from birds to humans or livestock. Successful dispersal techniques should capitalize on bird sensory capabilities. If birds cannot perceive the dispersal technique, …

Geese, Ducks And Coots, John L. Cummings

Wildlife Damage Management Technical Series

Canada geese, snow geese, ducks, and American coots all have been implicated in agricultural crop and turf damage. Canada geese and snow geese that graze on winter wheat and rye crops can reduce subsequent grain and vegetative yields. Canada geese also cause serious damage to sprouting soybeans in spring and to standing cornfields in the autumn. The most common damage to agricultural resources associated with geese results from consumption of crops. Other impacts involve unacceptable accumulations of feces in pastures, trampling of emerging crops, and increased erosion and runoff from fields where the cover crop has been grazed. Canada geese …

Double-Crested Cormorants, Brian S. Dorr, Kristi L. Sullivan, Paul D. Curtis, Richard Chipman, Russell D. Mccullough

Wildlife Damage Management Technical Series

The history of conflict between double-crested cormorants (Figure 1) and human interest in fisheries is long and convoluted. Following a low point in the 1970s, populations of cormorants expanded in North America, as did concerns about impacts on fisheries. By the late 1990s, natural resource agencies in 27 states reported losses of free-ranging fish stocks to cormorants. Agencies in 10 states, ranging from the Southwest to the Northeast, considered cormorant predation to be of moderate to major concern to fishery management.

Overall, double-crested cormorants are not major consumers of commercial and sportfish species. However, exceptions have been recorded at specific …