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The northern pocket gopher (Thomomys talpoides) is considered a major pest in haylands, particularly alfalfa, and surrounding crops and shelterbelts of western Canada. Although poison baits are often used with the objective to quickly reduce pocket gopher populations over large areas, recent investigations in western Canada have demonstrated that they were ineffective in reducing and controlling pocket gopher populations in haylands. This paper identifies the elements of an effective pocket gopher control program and demonstrates that, with a proper strategy to lay out killing traps in spring to remove breeders-of-the-year, and to intercept invading pocket gophers, trapping is the most effective method to control northern pocket gophers. This paper also describes an effective trapping program and identifies research needs to increase capture efficiency.

The northern pocket gopher (Thomomys talpoides) is considered a major pest in haylands, particularly alfalfa, and surrounding crops and shelterbelts of western Canada. Although poison baits are often used with the objective to quickly reduce pocket gopher populations over large areas, recent investigations in western Canada have demonstrated that they were ineffective in reducing and controlling pocket gopher populations in haylands. This paper identifies the elements of an effective pocket gopher control program and demonstrates that, with a proper strategy to lay out killing traps in spring to remove breeders-of-the-year, and to intercept invading pocket gophers, trapping is the most effective method to control northern pocket gophers. This paper also describes an effective trapping program and identifies research needs to increase capture efficiency.

The 2½-day Colorado Front Range Prairie Dog Technical Workshop was held in Fort Collins, Colorado, February 27-March 1, 2001. The workshop attracted about 250 attendees, mostly government personnel. Black-tailed prairie dogs (Cynomys ludovicianus) present numerous challenges to landowners and resource managers because they are considered a rare and important ecosystem component, but at the same time they can cause various kinds of damage and pose a disease hazard to humans and their domestic animals. Invited speakers updated the participants on the topics of prairie dog biology and ecology, legal status and distribution, socio-economic issues, management techniques and strategies, and current research. Special topics such as plague management and black-footed ferret re-introductions were also addressed. Several panel discussions on management challenges and options were held. Various perspectives were presented and there was considerable interaction on these volatile issues. There was a field trip to local prairie dog colonies to view and discuss conflicts and management options. In this paper, we summarize some of the key topics and perspectives brought up at the Workshop, in order to provide a broad synopsis of this highly contentious arena of human-wildlife conflict.

The monk parakeet (Myiopsitta monachus) is native to South America but has become established in several locations throughout the United States through purposeful and accidental releases. The species is unique among parrots in that it is not a cavity-nester, but instead it builds a bulky nest structure of sticks. Often, in its native range and in the United States, the parakeet selects a electric utility structure as a nest site. Material from the nest then can cause short-circuits that result in damage to the utility structure and a subsequent power outage. In south Florida, monk parakeet damage and associated outages have increased substan­tially in recent years. Although the full costs associated with the damage and the outages are not known, it is evident that current methods to manage the problem are inadequate. In 2001, to address the need for more effective management methods, Florida Power and Light Company initiated a project to identify and investigate new, potentially useful management alternatives. In this paper, we review what is currently known regarding the impacts of monk parakeets to electric utilities and we discuss the status of research to develop new methods to reduce these impacts.

Rodent damage research in Hawaii has evolved in response to shifts from large-scale monoculture agriculture, such as sugarcane, to cultivation of diversified high-value specialty crops, such as export ornamental nurseries and forestry products. Recent findings and renewed conservation awareness of the impact of predators, especially rodents, as important limiting factors of many of Hawaii’s endangered avifauna have stimulated increased efforts to reduce rodent depredation in conservation areas and other natural resources. Some of the early tools developed in agriculture have been incorporated and successfully used for protecting non-agricultural resources and new methods have been developed for current problems. This paper summarizes the rodent research that the National Wildlife Research Center’s Hawaii Field Station has conducted over these years of changing economic times and priorities.

The recent and rapid growth of the private “nuisance” wildlife control industry follows the unparalleled current period of urban and suburban expansion. Nuisance wildlife control businesses range from simple home-based services to sophisticated franchised businesses. The nuisance wildlife control operator may hold an advanced degree in the wildlife sciences, or simply be an entrepreneur without formal education or even background experience in wildlife. State and federal agencies may participate directly or indirectly in nuisance wildlife control, in activities ranging from dissemination of advice or information to actual participation in programs that may lead to removal of animals. Naturally, all of the activities associated with nuisance wildlife control concern the many individuals and organizations in North America that are interested in animal welfare and protection. This paper addresses some of their concerns. We present a survey, summary, and critical analysis of the nuisance wildlife control industry with a special emphasis on what we view as its most problematic and troubling aspects. We discuss model standards, based primarily on existing best practices, and speculate about the future of this activity.

The continued expansion of coyote activity to new areas, the growth and expansion of human populations, undiminished difficulties faced by livestock producers in managing predation, and highly polarized public values have challenged the abilities of a new generation of scientists and students to develop effective, socially acceptable predation management methods. Work by scientists at the National Wildlife Research Center, their students, and numerous cooperators has resulted in more than 150 research papers, reports, theses, and dissertations during the past decade, substantially increasing the body of knowledge of coyote management strategies and describing progress in the development of new management methods. Much of the effort has focused on research on non-lethal techniques, methods that are selective for individual problem animals, and procedures perceived by the public to be more humane. More than two-thirds of the predator research scientists now at the Center were hired during the past decade, bringing fresh perspectives and new talent to the pervasive problems of livestock predation by coyotes.

Benefit-cost analysis (BCA) involves comparing all of the gains and losses from a given wildlife damage management action or management technique over time in similar units, thereby providing a total picture of potential gains and losses to society. This technique is at the core of justifications for wildlife damage management efforts. BCA has been noticeably absent from the study of vertebrate pest management problems, and in the few studies where a BCA has been included, the analysis is incomplete. This paper provides an overview of the steps in a BCA, using specific wildlife damage examples to highlight and expand the technique for researchers interested in documenting these effects.

As the U.S. population has increased and the number and nature of problems caused by wildlife has changed, the focus of research conducted by USDA APHIS National Wildlife Research Center (NWRC) scientists has evolved to meet changing demands for effective solutions. This paper summarizes changes in the focus of NWRC Bird Research Program as reflected in 1) three surveys to determine priority research needs of the Wildlife Services (WS) program, 2) NWRC research literature produced in each of three decades since 1970, and 3) the focus of current research in the NWRC Bird Research Program. Many research needs of the WS program were consistently expressed in three programmatic research needs assessments (RNAs) conducted in 1989, 1996, and 2001, while others changed as new bird-human conflicts emerged. Blackbirds, starlings, waterfowl, gulls, wading birds, and cormorants were listed in all three RNAs, while pelicans and vultures are more recently expressed as a priority research needs. The major emphasis of NWRC bird research publications over the last three decades has been related to blackbirds, starlings, and grain crops. Songbirds also were a subject of many research publications during each of the last three decades. Waterfowl, gulls, and cormorants, as well as aviation, aquaculture, and endangered species, were subjects of increased research focus at the NWRC during the 1990s.

The pest management strategy for bovine tuberculosis (Tb) in New Zealand aims to achieve official freedom from Tb before 2012 and to eradicate the disease from livestock and wildlife. On farmland, regularly tested cattle and deer usually provide adequate surveillance of Tb presence in sympatric wildlife, but there are many other areas where livestock are absent or their densities too low to be useful. For these areas, Tb prevalence in the wildlife hosts must be surveyed directly but brushtail possums (Trichosurus vulpecula), the main host, make poor sentinels (indicators) for identifying Tb presence or absence. Consequently, persistent Tb can go undetected for long periods. The trials reported here assess the feasibility and practicality of alternative techniques for Tb surveillance in wildlife – the use of ‘spillover’ hosts as sentinels for detecting Tb presence or helping quantify its likely absence. Spillover hosts become infected mainly through interaction with other species. This paper will discuss the use of these species to detect both the presence and the spread of bovine Tb in wildlife in the central North Island of New Zealand.

This paper discusses the more common methods of mole control used in the U.S. Field efficacy data are presented with a new product, Kaput® Mole Gel Bait, containing 250 ppm warfarin. Initial field studies in St. Louis, MO with a 500-ppm warfarin bait in 1998 yielded 50% efficacy within 5 days. The following year, a 250-ppm warfarin gel bait yielded 85% efficacy after 7 days of application. Field tests conducted in Ohio resulted in 90% control of eastern moles. Results from a field test in Oregon using warfarin alternate formulation and diphacinone gel baits demonstrated 47% and 80% control of Townsend’s mole within 15 and 7 days respectively.

Persistence of unique rabies virus variants in a diverse array of terrestrial carnivores and insectivorous bats makes rabies control in the U.S. a complex task. The public health system in the U.S. is effective in keeping human deaths near zero each year in the face of enzootic wildlife rabies, but the annual cost of coexistence with the disease is high, exceeding $300 million. In addition, each year tens of thousands of people are impacted by anxiety, fear, and trauma associated with potential or actual rabies exposure to themselves and their domestic animals. Exclusion, proper storage and disposal of garbage, and removal of problem animals are often effective alternatives to address wildlife rabies threats at specific sites; however, oral rabies vaccination (ORV) is the only currently available technique that shows promise for wildlife rabies control on a broad geographic and species scale. In this paper, we discuss progress toward using ORV to contain specific terrestrial rabies virus variants in the U.S. and planning towards coordinated national efforts to explore the elimination of terrestrial variants of rabies virus in the U.S.

For centuries, trappers, inventors, naturalists, and biologists have searched for animal traps that met a variety of criteria, such as efficiency and durability. And, for at least the last century, individuals and organizations have fostered a movement that declares traps as inhumane, adding another criterion to the search. Trapping animals for fur, particularly for European markets, played an important role in the history, exploration, and settlement of North America, depressing the populations of some furbearer species almost past the point of recovery. Recovery of animal populations depressed through trapping, market hunting, and habitat loss became one of the first major partnership efforts among U.S. states and federal agencies in the developing science of wildlife management. Regulated trapping continues to be an important means for managing abundant furbearer populations, although the vagaries of fur markets and restrictive legislation in a number of states have made this an increasingly difficult task. For more than 50 years, scientists at the USDA Wildlife Services National Wildlife Research Center and its predecessors have engaged in cooperative research to improve animal traps and trapping systems. In the past decade, a series of actions culminated in the establishment of a national program to evaluate traps according to several criteria, including international standards for animal welfare, in order to develop guidelines for best management practices for trapping furbearers. This paper will briefly review the history of U.S. federal trap research and the status of the cooperative trap testing program.

The Cuban hutia (Capromys pilorides), known locally as the banana rat, is a large rodent native to Cuba. Endemic to the West Indies, most species of hutia are rare or extinct because of over-harvest, exotic species introductions, and habitat modifications by humans. An exception is the U.S. Naval Base at Guantanamo Bay, Cuba, where the Cuban hutia is very common and is responsible for a variety of damage and conflicts. Conflicts with humans include damage to landscaping, gnawing through cables, damage to vehicles, and the accumulation of large amounts of feces in residential areas. Additionally, hutia are primarily herbivores and botanists have documented substantial damage to native vegetation with little subsequent regeneration of many plant species. Current management focuses on population reduction by shooting and some trapping, followed by euthanasia or relocation to remote areas. Although there is little published information on the Cuban hutia, this paper presents a literature review, population survey data (1999-2000), and biological data from a sample of hutia collected in May 2001. It appears that the hutia, the largest native mammal in Cuba, is quite prolific and well adapted to exploit most habitats and plant foods. Some considerations, including advantages and disadvantages, of potential management techniques (habitat modification, exclusion, trapping, shooting, and toxicants) to reduce damage and conflicts with hutia are presented. Finally, several areas of additional data or research needs are identified.

Canada geese have become established and are now numerous enough in many urban and suburban areas that conflicts with humans have become frequent. Although potential threats to human health are often cited as a justification to manage goose populations, currently available science suggests that this is not a serious issue. This leaves the primary concern as one of aesthetics– people do not like having to deal with what can sometimes be copious amounts of goose droppings. Animal welfare interests have questioned the humaneness of different roundup and killing programs, and advocated non-lethal approaches and egg addling. Both approaches currently are being practiced in a number of different communities without, unfortunately, much being done to systematically monitor or evaluate them. This paper addresses some of the more controversial issues surrounding resident Canada goose management from an animal welfare perspective and touches on some of the different management approaches currently being practiced as examples of the need for better overall coordination and comparison of management approaches.

Persistence of unique rabies virus variants in a diverse array of terrestrial carnivores and insectivorous bats makes rabies control in the U.S. a complex task. The public health system in the U.S. is effective in keeping human deaths near zero each year in the face of enzootic wildlife rabies, but the annual cost of coexistence with the disease is high, exceeding $300 million. In addition, each year tens of thousands of people are impacted by anxiety, fear, and trauma associated with potential or actual rabies exposure to themselves and their domestic animals. Exclusion, proper storage and disposal of garbage, and removal of problem animals are often effective alternatives to address wildlife rabies threats at specific sites; however, oral rabies vaccination (ORV) is the only currently available technique that shows promise for wildlife rabies control on a broad geographic and species scale. In this paper, we discuss progress toward using ORV to contain specific terrestrial rabies virus variants in the U.S. and planning towards coordinated national efforts to explore the elimination of terrestrial variants of rabies virus in the U.S.

Rodent damage research in Hawaii has evolved in response to shifts from large-scale monoculture agriculture, such as sugarcane, to cultivation of diversified high-value specialty crops, such as export ornamental nurseries and forestry products. Recent findings and renewed conservation awareness of the impact of predators, especially rodents, as important limiting factors of many of Hawaii’s endangered avifauna have stimulated increased efforts to reduce rodent depredation in conservation areas and other natural resources. Some of the early tools developed in agriculture have been incorporated and successfully used for protecting non-agricultural resources and new methods have been developed for current problems. This paper summarizes the rodent research that the National Wildlife Research Center’s Hawaii Field Station has conducted over these years of changing economic times and priorities.

This paper discusses the more common methods of mole control used in the U.S. Field efficacy data are presented with a new product, Kaput® Mole Gel Bait, containing 250 ppm warfarin. Initial field studies in St. Louis, MO with a 500-ppm warfarin bait in 1998 yielded 50% efficacy within 5 days. The following year, a 250-ppm warfarin gel bait yielded 85% efficacy after 7 days of application. Field tests conducted in Ohio resulted in 90% control of eastern moles. Results from a field test in Oregon using warfarin alternate formulation and diphacinone gel baits demonstrated 47% and 80% control of Townsend’s mole within 15 and 7 days respectively.

Canada geese have become established and are now numerous enough in many urban and suburban areas that conflicts with humans have become frequent. Although potential threats to human health are often cited as a justification to manage goose populations, currently available science suggests that this is not a serious issue. This leaves the primary concern as one of aesthetics– people do not like having to deal with what can sometimes be copious amounts of goose droppings. Animal welfare interests have questioned the humaneness of different roundup and killing programs, and advocated non-lethal approaches and egg addling. Both approaches currently are being practiced in a number of different communities without, unfortunately, much being done to systematically monitor or evaluate them. This paper addresses some of the more controversial issues surrounding resident Canada goose management from an animal welfare perspective and touches on some of the different management approaches currently being practiced as examples of the need for better overall coordination and comparison of management approaches.

The continued expansion of coyote activity to new areas, the growth and expansion of human populations, undiminished difficulties faced by livestock producers in managing predation, and highly polarized public values have challenged the abilities of a new generation of scientists and students to develop effective, socially acceptable predation management methods. Work by scientists at the National Wildlife Research Center, their students, and numerous cooperators has resulted in more than 150 research papers, reports, theses, and dissertations during the past decade, substantially increasing the body of knowledge of coyote management strategies and describing progress in the development of new management methods. Much of the effort has focused on research on non-lethal techniques, methods that are selective for individual problem animals, and procedures perceived by the public to be more humane. More than two-thirds of the predator research scientists now at the Center were hired during the past decade, bringing fresh perspectives and new talent to the pervasive problems of livestock predation by coyotes.

Benefit-cost analysis (BCA) involves comparing all of the gains and losses from a given wildlife damage management action or management technique over time in similar units, thereby providing a total picture of potential gains and losses to society. This technique is at the core of justifications for wildlife damage management efforts. BCA has been noticeably absent from the study of vertebrate pest management problems, and in the few studies where a BCA has been included, the analysis is incomplete. This paper provides an overview of the steps in a BCA, using specific wildlife damage examples to highlight and expand the technique for researchers interested in documenting these effects.

The monk parakeet (Myiopsitta monachus) is native to South America but has become established in several locations throughout the United States through purposeful and accidental releases. The species is unique among parrots in that it is not a cavity-nester, but instead it builds a bulky nest structure of sticks. Often, in its native range and in the United States, the parakeet selects a electric utility structure as a nest site. Material from the nest then can cause short-circuits that result in damage to the utility structure and a subsequent power outage. In south Florida, monk parakeet damage and associated outages have increased substan­tially in recent years. Although the full costs associated with the damage and the outages are not known, it is evident that current methods to manage the problem are inadequate. In 2001, to address the need for more effective management methods, Florida Power and Light Company initiated a project to identify and investigate new, potentially useful management alternatives. In this paper, we review what is currently known regarding the impacts of monk parakeets to electric utilities and we discuss the status of research to develop new methods to reduce these impacts.

The 2½-day Colorado Front Range Prairie Dog Technical Workshop was held in Fort Collins, Colorado, February 27-March 1, 2001. The workshop attracted about 250 attendees, mostly government personnel. Black-tailed prairie dogs (Cynomys ludovicianus) present numerous challenges to landowners and resource managers because they are considered a rare and important ecosystem component, but at the same time they can cause various kinds of damage and pose a disease hazard to humans and their domestic animals. Invited speakers updated the participants on the topics of prairie dog biology and ecology, legal status and distribution, socio-economic issues, management techniques and strategies, and current research. Special topics such as plague management and black-footed ferret re-introductions were also addressed. Several panel discussions on management challenges and options were held. Various perspectives were presented and there was considerable interaction on these volatile issues. There was a field trip to local prairie dog colonies to view and discuss conflicts and management options. In this paper, we summarize some of the key topics and perspectives brought up at the Workshop, in order to provide a broad synopsis of this highly contentious arena of human-wildlife conflict.

The pest management strategy for bovine tuberculosis (Tb) in New Zealand aims to achieve official freedom from Tb before 2012 and to eradicate the disease from livestock and wildlife. On farmland, regularly tested cattle and deer usually provide adequate surveillance of Tb presence in sympatric wildlife, but there are many other areas where livestock are absent or their densities too low to be useful. For these areas, Tb prevalence in the wildlife hosts must be surveyed directly but brushtail possums (Trichosurus vulpecula), the main host, make poor sentinels (indicators) for identifying Tb presence or absence. Consequently, persistent Tb can go undetected for long periods. The trials reported here assess the feasibility and practicality of alternative techniques for Tb surveillance in wildlife – the use of ‘spillover’ hosts as sentinels for detecting Tb presence or helping quantify its likely absence. Spillover hosts become infected mainly through interaction with other species. This paper will discuss the use of these species to detect both the presence and the spread of bovine Tb in wildlife in the central North Island of New Zealand.

The Cuban hutia (Capromys pilorides), known locally as the banana rat, is a large rodent native to Cuba. Endemic to the West Indies, most species of hutia are rare or extinct because of over-harvest, exotic species introductions, and habitat modifications by humans. An exception is the U.S. Naval Base at Guantanamo Bay, Cuba, where the Cuban hutia is very common and is responsible for a variety of damage and conflicts. Conflicts with humans include damage to landscaping, gnawing through cables, damage to vehicles, and the accumulation of large amounts of feces in residential areas. Additionally, hutia are primarily herbivores and botanists have documented substantial damage to native vegetation with little subsequent regeneration of many plant species. Current management focuses on population reduction by shooting and some trapping, followed by euthanasia or relocation to remote areas. Although there is little published information on the Cuban hutia, this paper presents a literature review, population survey data (1999-2000), and biological data from a sample of hutia collected in May 2001. It appears that the hutia, the largest native mammal in Cuba, is quite prolific and well adapted to exploit most habitats and plant foods. Some considerations, including advantages and disadvantages, of potential management techniques (habitat modification, exclusion, trapping, shooting, and toxicants) to reduce damage and conflicts with hutia are presented. Finally, several areas of additional data or research needs are identified.

The recent and rapid growth of the private “nuisance” wildlife control industry follows the unparalleled current period of urban and suburban expansion. Nuisance wildlife control businesses range from simple home-based services to sophisticated franchised businesses. The nuisance wildlife control operator may hold an advanced degree in the wildlife sciences, or simply be an entrepreneur without formal education or even background experience in wildlife. State and federal agencies may participate directly or indirectly in nuisance wildlife control, in activities ranging from dissemination of advice or information to actual participation in programs that may lead to removal of animals. Naturally, all of the activities associated with nuisance wildlife control concern the many individuals and organizations in North America that are interested in animal welfare and protection. This paper addresses some of their concerns. We present a survey, summary, and critical analysis of the nuisance wildlife control industry with a special emphasis on what we view as its most problematic and troubling aspects. We discuss model standards, based primarily on existing best practices, and speculate about the future of this activity.

For centuries, trappers, inventors, naturalists, and biologists have searched for animal traps that met a variety of criteria, such as efficiency and durability. And, for at least the last century, individuals and organizations have fostered a movement that declares traps as inhumane, adding another criterion to the search. Trapping animals for fur, particularly for European markets, played an important role in the history, exploration, and settlement of North America, depressing the populations of some furbearer species almost past the point of recovery. Recovery of animal populations depressed through trapping, market hunting, and habitat loss became one of the first major partnership efforts among U.S. states and federal agencies in the developing science of wildlife management. Regulated trapping continues to be an important means for managing abundant furbearer populations, although the vagaries of fur markets and restrictive legislation in a number of states have made this an increasingly difficult task. For more than 50 years, scientists at the USDA Wildlife Services National Wildlife Research Center and its predecessors have engaged in cooperative research to improve animal traps and trapping systems. In the past decade, a series of actions culminated in the establishment of a national program to evaluate traps according to several criteria, including international standards for animal welfare, in order to develop guidelines for best management practices for trapping furbearers. This paper will briefly review the history of U.S. federal trap research and the status of the cooperative trap testing program.

As the U.S. population has increased and the number and nature of problems caused by wildlife has changed, the focus of research conducted by USDA APHIS National Wildlife Research Center (NWRC) scientists has evolved to meet changing demands for effective solutions. This paper summarizes changes in the focus of NWRC Bird Research Program as reflected in 1) three surveys to determine priority research needs of the Wildlife Services (WS) program, 2) NWRC research literature produced in each of three decades since 1970, and 3) the focus of current research in the NWRC Bird Research Program. Many research needs of the WS program were consistently expressed in three programmatic research needs assessments (RNAs) conducted in 1989, 1996, and 2001, while others changed as new bird-human conflicts emerged. Blackbirds, starlings, waterfowl, gulls, wading birds, and cormorants were listed in all three RNAs, while pelicans and vultures are more recently expressed as a priority research needs. The major emphasis of NWRC bird research publications over the last three decades has been related to blackbirds, starlings, and grain crops. Songbirds also were a subject of many research publications during each of the last three decades. Waterfowl, gulls, and cormorants, as well as aviation, aquaculture, and endangered species, were subjects of increased research focus at the NWRC during the 1990s.