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In recent years, there has been increasing interest in the use of carbon monoxide-generating devices to control burrowing rodents. A pilot study was performed to determine how long a black-tailed prairie dog burrow needed to be fumigated with a BurrowRx® machine to obtain control. This pilot study obtained 92% efficacy with a four-minute injection, 86.7% with a 3:45-minute injection and 90% efficacy with a three-minute injection. Out of 59 burrows, 85% had only a single entrance. Of the nine that had two or more openings, six had only two, one had three openings, and two had five openings. Surface measurements from the treated opening to the furthest connected opening ranged from 10 feet to 43 feet with the average being 23.33 feet. The paper also discusses suggestions for further research and suggestions for practical use of the device.

This paper reviews the Vertebrate Pest Conference’s beginnings, why it started, and assesses its success in meeting the goals articulated during the opening Conference in 1962. Probably moreso than any other state, California has a diversity of agriculture that gives every vertebrate a chance to become a pest, even those that didn’t originally live in the state. This, and the hard work of Conference founders, made California a logical place to develop a first-rate Conference on all aspects of vertebrate pests. At the first Conference, over 80% of attendees were from California. At the 24th Conference, this had changed with over 40% attendees from other states and almost 10% from other countries. During the first Conferences, the presentations were mostly about current control methods for various vertebrate pests. Now, the topics have shifted to deal more with specific aspects of control such as non-target impacts, pesticide metabolism, etc. The Conference Proceedings have evolved from a collection of 25 “how-to” papers in the first Proceeding to over 75 peer-edited papers in the 24th. Many of these papers, especially in the more recent Conference Proceedings, are cited throughout the international vertebrate pest control literature. Another trend has been the publication of multiple-authored papers. This represents the important goal of the Conference of getting people together to discuss and work on understanding all aspects of vertebrate pest control. It is clear, just by looking around at the audience and reviewing the program for the 25th Conference, that the VPC is doing exactly what the founders envisioned, and in my opinion, it is an unconditional success!

Papers presented at two long-running conferences, the Australasian Vertebrate Pest Conference and the USA Vertebrate Pest Conference, were reviewed to examine changes in the field of vertebrate pest management over the last few decades. At both conferences, there has been a shift in focus from pest impacts on production (crop, livestock, forestry etc.) to impacts on conservation values. Papers have also become more focussed with a decrease in papers on pest problem overviews. There were surprisingly few papers focussing on the human dimensions of vertebrate pest management, despite general acknowledgment that the public have become more involved in pest management decision-making. The number of papers presented and number of pest species addressed has also increased, indicating the importance of these conferences to pest management professionals for sharing information and ideas.

Brown treesnakes are exotic invasive predators that have extirpated native forest birds and caused drastic reductions of lizards on Guam. Operational management control methods to contain the snake on Guam include the use of live traps, hand capture from fences, and canine detection. Live traps are also used to depopulate small forest plots. Toxicants offer an additional means for reducing snake populations on small plots. Polyvinyl chloride (PVC) plastic pipe bait stations containing dead neonatal mice (DNM) treated with 80 mg acetaminophen are placed about 1.5 m above the ground in vegetation to reduce exposure to terrestrial scavengers such as toads, crabs, and feral pigs. Live traps or bait stations are not practical to use in remote, large-scale areas of forest but aerial delivery of baits may have application. Small plastic parachutes have been used for entangling DNM in forest canopy but parachutes are relatively expensive and cumbersome to use. Inconveniences can be tolerated when only a small number are deployed. But it is anticipated that several thousand baits may be delivered per drop, and inconveniences must be kept to a minimum to maintain an efficient aerial drop system. We therefore evaluated 5 types of flotation materials dropped by helicopter, using DNM implanted with radio transmitters to record landing site (canopy or ground) and bait consumption by snakes and non-target animals. The types of material and percentage of baits that became entangled in the canopy were: paper ring – 39%, paper drinking cup – 50%, excelsior (wood shavings) and burlap – each 56%, and commercial paper food cup – 60%. For all devices, bait consumption by snakes ranged from 19-50% and bait consumption by non-target toads and crabs ranged from 0 - 11%. Commercial food cups were the most convenient material to use because they could be nested together prior to deployment.

In the late 1800s, the small Indian mongoose was introduced to the Caribbean islands in one of the most widespread purposeful introductions of a mammalian predator in history. Intended as a biological control agent for introduced rats in sugarcane plantations, the mongoose quickly became recognized as a pest due to its predation on poultry and native fauna, and injuries to livestock. Over the last 40 years, the mongoose has also emerged as the primary vector and reservoir for rabies on several Caribbean islands. Due to the estimated costs associated with this introduced carnivore, as well as potential ecological impacts, the mongoose is now listed as one of the top 100 worst invaders by the IUCN. Past large-scale control attempts in the Caribbean have proven unsuccessful, and few to none are currently being implemented. In fact, despite its renown, very little is known about the actual impacts of the mongoose. It is likely that combined with increasing rates of development in some Caribbean islands, the impact of the mongoose on native faunal communities may become more serious. This paper provides an overview of mongoose management in the Caribbean. Although current management priorities center on the role and management of the mongoose as a disease vector, this paper will also discuss opportunities to pair this research with 1) an assessment of the ecological impacts of the mongoose on native species, and 2) the development of mongoose control methods. The Caribbean National Forest, Puerto Rico is used as a case study; however, these methods can potentially apply to other Caribbean islands.

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.

After several years of reviewing study data and conducting risk assessments, in September of 1998 the U.S. Environmental Protection Agency (U.S. EPA) issued for comment a Reregistration Eligibility Decision (RED) document for pesticide products in the Rodenticide Cluster. The RED document covered 243 rodenticide products containing the following active ingredients: brodifacoum, bromadiolone, bromethalin, chlorophacinone, diphacinone and its sodium salt, and pival and its sodium salt. The U.S. EPA’s human health risk assessment in the RED document concluded that it was concerned about the risk to children due to accidental exposures to these chemicals through use in and around residences. With regard to ecological effects, the Agency concluded that there is a high risk of secondary poisoning, especially to mammals, from the use of these rodenticides outdoors in rural and suburban areas. In order to address the potential risks to children, the U.S. EPA initially required several mitigation measures designed to minimize exposure (e.g., addition of dye and bittering agent to formulations, labeling changes). The Agency also initiated implementation of a Rodenticide Stakeholder Process through which these and other risk mitigation measures would be discussed and required as needed. To help mitigate potential risks to non-target wildlife, the Agency initially determined that all uses of field-bait rodenticides containing more than 0.005% of chlorophacinone or diphacinone were ineligible for reregistration. The U.S. EPA also decided that all rodenticide products labeled for field use (except those limited to manual underground baiting) should be reclassified as Restricted Use pesticides. This paper reviews the regulatory process for the Rodenticide Cluster RED and discusses the response of the California Department of Food and Agriculture (CDFA) and other registrants to the requirements proposed in the RED document including formation of the Rodenticide Registrants Task Force (RRTF). It also outlines how an on-going dialogue with the Agency, both through the Rodenticide Stakeholder Process and in separate discussions, has diminished the RED requirements from those originally proposed. In addition, the paper discusses the implications and potential impacts of the current RED reregistration requirements for those applicators involved in agricultural and urban rodent control.

This paper presents a methodological approach that was recently developed to determine alternatives for control of California ground squirrels (Spermophilus beecheyi) and the resulting ecological consequences at the Concord Naval Weapons Station (CNWS). The U.S. Navy initiated this study upon determining a need to control ground squirrels for safety reasons. The squirrel's ecological role at CNWS was examined by estimating squirrel abundance and distribution throughout CNWS, analyzing predator diets, and determining the squirrel's relationship to the California tiger salamander (Ambystoma californiense). In addition, the efficacy of live capture and translocation of squirrels as a possible control method was specifically examined using an experimental approach. Finally, alternative control measures are reviewed and discussed in the context of our results. The emphasis of this paper is on the methods employed and the discussion of alternatives as an example of an ecologically-based approach to control programs. As wide-scale poisoning control programs have recently come under public opposition in the courts and otherwise, studies such as these will serve to direct future management efforts toward control programs that consider several alternatives and their ecological effects.

A 2012 attempt to remove two rat species (Rattus tanezumi and R. exulans) from Wake Atoll was partially successful. R. tanezumi was eradicated from all three islands (Wake, Wilkes, and Peale), and R. exulans was eradicated from Peale. However, R. exulans remained on Wake and Wilkes and have since recovered to very high densities. In 2013, a panel of experts reviewed the eradication operation and offered a list of possible causes of the partial failure. Since that time, further research has been conducted to address several of the issues identified in the review. In this paper, we conduct a current review of the remedial studies, identify remaining knowledge gaps, and make recommendations for ensuring the feasibility of a future operation to remove R. exulans from Wake and Wilkes Islands.

The economically and ecologically catastrophic introduction of invasive brown treesnakes to the Pacific Island of Guam has long served as a cautionary tale about the dangers of invasive species and the seeming impossibility of their management on a landscape scale. USDA Wildlife Services and federal and private partners have engineered a system for the automated manufacture and aerial delivery of toxic baits for landscape-scale suppression of brown treesnakes in large and remote forest plots. The helicopter-borne dispensing module can launch four bait cartridges per second, and a single payload of 3,600 cartridges can treat 30 ha of forest at 120 baits/ha in 15 to 30 minutes depending on flightpath efficiency. In this paper we recap the research, development, testing, and implementation of the system, including the procedures for monitoring biological responses to bait applications during an experimental suppression within a 55-ha forest plot surrounded by a snake-proof barrier.

Use of M-44 sodium cyanide devices has been opposed by various groups contending that M-44s threaten human health and safety and endanger non-target animals. In Montana, M-44 sodium cyanide devices may be used by non-USDA-Wildlife Services individuals licensed by the Montana Department of Agriculture. This paper summarizes the use data submitted by these non-federal applicators between 2006-2019. The data includes use records, take (both target and non-target), and livestock loss reports. It is hoped that this information provides additional data and context to inform the debate over this controversial predator management tool.

Island rodent eradication operations have been remarkably successful at eliminating damages caused by these harmful vertebrate pests. As efforts increase in scale and complexity, so does risk of eradication failure. In this paper we present the example of a partially successful rodent eradication project to highlight how best practices and lessons learned are being integrated to reduce risk of failure during a second attempt. In 2012 the U.S. Air Force (USAF) commissioned an attempted eradication of two rat species from Wake Atoll in the Western Pacific. Asian house rats were successfully eradicated, but it was soon confirmed that some Polynesian rats survived; population numbers have since soared. A panel of outside experts was asked to review the project and identify factors that may have contributed to failure. The USAF and Wildlife Services National Wildlife Research Center (NWRC) have used this report as a road map for further studies addressing issues including bait delivery strategies, bait application rates, and alternate bait formulations. A subsequent data gap analysis conducted by USAF, NWRC, and Island Conservation documented technical advances in the intervening years that address risk factors identified in the original review, and highlighted remaining needs including development of a community outreach component and refinement of baiting strategies for inhabited areas and abandoned structures. This exchange of knowledge and expertise among cooperating organizations is helping to refine feasibility assessments and address lingering knowledge gaps. These efforts include a review of other failed rodent eradications that were redone successfully. Ongoing studies continue to resolve areas of uncertainty, and results are being integrated into operational planning for a subsequent eradication effort on Wake Atoll. This process highlights the importance of ongoing refinement of best practices, incorporation of lessons learned, and transfer of knowledge to the wider eradication community.

The common vampire bat apparently is expanding its range northwards in Mexico and seems poised to enter the southern United States. Climate models predict suitable habitat in the U.S. in south Texas and parts of southern Arizona. While vampire bats’ northward range expansion is not unexpected, the fact that this species brings a strain of rabies that impacts livestock and people warrants a strategic response. Annual economic damages from bats are estimated between $7M and $9M, largely associated with deaths of livestock from rabies. To prepare for the emerging rabies issue, USDA Wildlife Services programs in Texas and Arizona have begun training employees to recognize symptoms and respond to bat presence. Surveillance of livestock at sale barns and on ranches is designed to maximize the opportunity to detect bat bites in livestock. Outreach on the issue, via one-on-one training and a DVD handout to landowners along both sides of the border, has been initiated. This paper details the extent of preparations for an emerging disease; quantifies expenditures necessary for a responsive program; and discusses some issues associated with the proximity of vampire bats to the U.S.-Mexico border.

Field trials are reported in this paper on a new bait containing 1% norbormide. Two separate field trials were recently completed on commercial chicken farms in South Auckland, New Zealand. Norway rats were abundant both inside the farm sheds and around the surrounding farmland. Monitoring undertaken before toxic baiting recorded high levels of rat activity. Post-treatment monitoring found no rat paw prints in any of the tracking tunnels from Site 1, and in only one tunnel at Site 2. The decrease of 100% and 96%, respectively, represented a marked reduction in the Norway rat population at both sites.

Those who have been in the field of wildlife damage management very long probably have a file drawer full of half-baked ideas and ill-fated research projects that never should have seen the light of day. This paper will be a tongue-in-cheek look at the scientific method and saving grace of pilot studies. A pilot study is a small-scale test of the procedures to be used in a large-scale study. The goal of pilot work is not supposed to be the testing of hypotheses, but sometimes researchers just can’t help themselves. Beware of small sample sizes and the potential for false negative and false positive results. I have been involved in more pilot studies than I care to admit that ended up being a total bust, but there have been some that led to well-informed modifications of study designs and results that were immediately publishable because the variation in resultant data was low and results were clear cut. Pilot studies have expanded my knowledge of systems, study design, methodology, and the behavior of individual animals. I encourage the use of pilot studies in research associated with vertebrate pest management.

Beginning in 2009, the Army’s Natural Resource Program on O’ahu implemented the first of three ecosystem-scale rat trapping grids of traditional snap traps in the Waianae Mountains using the model outlined in The New Zealand Department of Conservation’s current best practices for kill-trapping rats. Traps were generally checked every two weeks, but bait often remained palatable for just a few nights due to slug interference. Because of the amount of labor required for single set traps, trials with Goodnature A24 self-resetting traps were conducted from 2014-2016. Early findings showed that traps were malfunctioning at a rate of ~25% and there were major deficiencies with the bait and bait-delivery system. In 2016 the bait system was improved when Goodnature developed the automatic lure pump that continually releases fresh bait for ~4-6 months. Other improvements were also made to the A24 trap to decrease the malfunction rate. In 2017, we replaced more than 1,300 snap traps at all ecosystem-scale grids with 1,000 A24s. Tracking tunnels were used as an independent monitoring system to determine rat control effectiveness. At all sites, rat activity measured in the tracking tunnels has been low (less than 15%) for over 18 months. In this paper we discuss the results of the transition from single- to multi-set rat traps, highlights some successes and obstacles, and describes grid spacing and applicability to other sites.

Constant developments in technology, both materials and methods, allow smaller and smaller animals to be radio-tracked for longer periods of time than was previously possible. Developments in electronic component miniaturization and battery chemistry are primarily responsible for this advancement. Approximately 30 years of field-use of radiotelemetry techniques have led to innovative procedures and uses of materials for the application of transmitters to animals. New technology such as satellite telemetry and recapture collars are only in their infancy and are not, at this time, appropriate for use in vertebrate pest research. Sophistication in receiving systems also allows more accurate and more complete data to be collected. This paper is not intended to be a review of telemetry devices on the cutting-edge of technology or non-field-proven developmental systems, but rather presents an overview of currently available, on-the-market technology appropriate for use by vertebrate pest researchers. As it is a review paper, not a research paper, it does not strictly follow the standard research paper format.

In India, as in other countries, problems associated with locally overabundant wildlife species have emerged as important management issues for reason of some species losing their natural habitat but adapting themselves to the man-altered habitats. Consequently, there is a clash with the interests of local people. Crop-raiding by locally overabundant wild populations of nilgai and blackbuck in Haryana is one such problem analyzed in this paper. Nilgai causes extensive damage to agricultural crops; among these, gram, wheat seedlings and moong are the most preferred ones. Blackbuck nibble mainly on young shoots of various cereal and pulse crops and the damage is much less than caused by nilgai. Possible management strategies such as culling, fencing in nilgai and black buck (enclosures or corrals), and fencing agricultural areas to minimize the problem are suggested. Chain-link fencing of a sizable Reserved Forest (RF) patch, where the animals seek daytime shelter, combined with other local protective methods in the cultivated areas of Nahar hold promise of reducing the pest animal populations. The experiment is likely to establish one approach for dealing with the specific problem in Haryana. This paper discusses agricultural crop-raiding by locally overabundant populations of nilgai (Boselaphus tragocamelus) and blackbuck (Antilope cervicapra) in several districts of Haryana and the possible management strategies that can limit or reduce the conflict. Based on these strategies, a management experiment is being conducted in one of the districts, namely, Nahar, and its results are presented in this paper.

Effective management of rodent pests requires an ecological understanding of how they move through their environment, and how those movements influence the invasion, persistence, or reinvasion of problematic colonies. Traditional methodologies used to describe rodent movement patterns, such as mark-recapture, are hindered by their time-consuming nature and limited geographic scope. As such, our understanding of how rodents interact with urban environments remains limited. Population genetic principles and tools have the capacity to greatly increase our understanding of rodent population dynamics, ecological relationships, and movements across space but this field is often unapproachable to non-scientist pest management professionals. In this paper we aim to promote collaborative and integrative rodent pest management by introducing relevant population genetic principles, providing examples of their applications in studies of urban brown rats, and proposing future initiatives that link scientific, private, and government entities. Using a densely-sampled brown rat population in the city of Vancouver, BC we show how genetic relationships among individual brown rats can be leveraged to understand the geographic distribution of genetic clusters (i.e., colonies), natural barriers to migration, and the spatial scale of dispersal. We describe how these results can be exploited by PMPs to directly inform the creation of management units and decrease the likelihood of rapid post-treatment reinvasion. Further, we discuss the difficulties inherent in population genetic studies and the potential for high-quality model sites to develop generalizable strategies. Overall, we hope to expand the toolbox of pest management professionals, foster collaboration, and move towards more informed and sustainable management strategies.

Rodenticides are an essential tool in the integrated pest management (IPM) of infestations of commensal rodents. With the introduction of Assembly Bill 2422 California Natural Predator Protection Act, the State of California is potentially facing a future with serious restrictions on the use of anticoagulant rodenticides to manage commensal rodents in urban areas. Assembly Bill 2422 has been proposed to protect predators from rodenticide poisoning and seeks to significantly restrict the application of first and second generation anticoagulant rodenticides for use in many urban and no-urban areas of California. Exclusion and cultural practices, such as landscape management and sanitation, are important and successful tools for managing rodent populations. However, quick and efficient control of commensal rodent infestations often necessitates the use of rodenticides. While rodenticide is an important tool, exposure of wildlife to anticoagulant rodenticides has been evident for many years in the state of California. When rodents are consumed by predators, second generation anticoagulant rodenticides can be detected as residues in the livers of predators. Many species of animals are documented as having succumbed to rodenticide toxicosis, however the effects of chronic, sub-lethal exposure to predators are not well understood. This paper will discuss the current and proposed changes to rodenticide legislation in California, impacts of the legislation on communities across California, and gaps in research preventing the adoption of evidence-based best management strategies for rodent control. In order to improve the success of commensal rodent control programs in California, effective strategies for rodent management must be developed.

After centuries of persecution, European wolf populations are recovering across many areas due to favorable legislation and the rise of the “rewilding” movement over the past few decades. The central mechanism triggering the rewilding of Europe was the European Union Habitat Directive, approved in May of 1992. The directive classifies the wolf as a strictly protected species and all EU-countries have implemented the directive in their legislation. Since the 1990’s, the number of wolves in Europe has steadily increased and the total number of wolves, excluding Russia, Belarus and Ukraine, exceeds 12,000 wolves. At the same time conflicts between farmers, wolf protectors and authorities are becoming more frequent. Wolves living in Central Europe, Finland and Scandinavia must cope with the fact that there are human settlements throughout their habitat. This results in a strong habituation to humans and a growing number of attacks against cattle and sheep under the cover of darkness as well during dawn, dusk, and night. The appearance of wolves in settled areas in broad daylight seems to be more and more the rule rather than the exception. While authorities explain this as being a part of the wolf's normal behavior, human tolerance in areas where wolves return is rapidly lowering. Wolves’ depredation on livestock, and especially a behavior called surplus killing, has resulted in several clashes between farmers and authorities in France and Italy. Surplus killing is a behavior exhibited by wolves in which they kill more prey than they are able to consume and then abandon the remainder. Incidents from Southern Europe show that a single wolf pack may kill hundreds of sheep in one single attack. In this paper I will review the implications of human-wolf coexistence in settled areas in different parts of Europe. I will highlight a number of problems experienced as well as solutions and their outcome.

In 1978, Point Reyes National Seashore (PRNS) reintroduced Tule elk, which is the only National Park unit where Tule elk can be found. The State of California provided the initial elk Tomales Point in PRNS. State wildlife biologists were members of the team that managed the re-introduction and subsequent monitoring. Tomales Point is a fenced area; however, one goal of the 1998 Tule Elk Management Plan was to establish a free-ranging Tule elk herd to the seashore. That plan stated the forage is unaffected by the number of elk occupying the range and elk do not have a strictly negative effect on vegetation. However, in 1999, PRNS moved a free-range herd of 28 elk from Tomales Point to the wilderness area near Limantour Beach. Within weeks, a few elk unexpectedly migrated to ranches in the designated pastoral zone. Currently, Drakes Beach (D Ranch) herd includes approximately 150 Tule elk. Designated pastoral zone, where livestock and dairy producer operations may be permitted, are charged an annual lease based on the lands’ carrying capacity. In 2004, beef and dairy producers began to express concerns about the impacts elk were having on forage, organic certifications, and overall economic viability. In 2014, PRNS initiated the Ranch Comprehensive Management Plan to assess growing concerns of beef and dairy producers related to the free-ranging elk impacts to the pastoral zone. PRNS staff have not implemented any of their 1998 control methods, and are currently only hazing elk away from permitted operations. The efficacy of hazing elk away from the pastoral zone is in question; and PRNS has stated an inability to do more control due to recent litigation. Efforts should focus on non-lethal effective elk management options, such as contraception, which abide by current litigation constraints while mitigating producer burden and concern. The objective of this paper is to develop a case for potential multi-species management (i.e., elk plus cattle) at PRNS while protecting its historical, biodiversity, and economic value.

Fleas are remarkable and highly specialized insects, with no part of their external anatomy being easily mistaken for that of any other insect. Due to their small size, the subtle differences among the distinguishing morphological characteristics of each species, and complexities of preparing specimens, identifying, and working with fleas is challenging. Various documents and taxonomic keys are available that discuss mounting procedures and the identification of medically important fleas for large regions of the world including the United States; however, many of these have become antiquated over time. Some of the distinguishing specialized characteristics exhibited among flea species, as presented in older keys, come in the form of line drawings, which are accurate but can be difficult to use when comparing it to structures on a whole specimen when viewed through a microscope. This paper presents a guide which describes in detail previously developed, but obscure techniques covering the preservation, preparation, clearing, and mounting of Siphonaptera specimens. In addition, we are also presenting an easy-to-use photographic key of twelve flea species collected from back yard wildlife, as well as pet cats and dogs in Orange County, CA. This key, which is freely available online at the Orange County Mosquito and Vector Control District’s website, is an effective tool for the identification of common flea species found in southern California. Using the key in conjunction with the mounting guide will provide users with a full-circle guide to preserving, identifying, and mounting flea specimens. Keyed flea genera include Cediopsylla, Ctenocephalides, Diamanus, Echidinophaga, Hoplopsyllus, Leptopsylla, Nosopsyllus, Orchopoeas, Pulex, and Xenopsylla. Examined hosts include cats, coyotes, dogs, mice, opossums, rabbits, raccoons, rats, skunks, squirrels, and woodrats.

Wildlife resources in southern Africa are remarkably beautiful, ecologically indispensable, and culturally critical to people of the region. Unfortunately, those who reside in rural areas (veldt) face remarkable risks every day when living and dealing with lions, leopards, elephants, crocodiles, and other creatures that go “bump” in the night. The loss of human life and limb is higher than most would ever think. In addition, loss of livestock and crops to wildlife is widespread and can be locally severe. The significance and severity of human-wildlife conflicts in southern Africa seem to be an order of magnitude greater than in North America. During the last decade, I have had the good fortune to work on several projects, including field research, lectures, symposia, keynote addresses, internships, and a reference book dealing with human-wildlife conflicts in southern Africa. It has been a lifechanging experience. This paper provides details on the projects we have established to help resolve human-wildlife conflicts in southern Africa.

Interest groups are lobbying local authorities nationwide to manage the increasingly dangerous problem of nuisance urban-coyotes by adopting a so-called “hazing” regime, whereby the populace is educated to actively engage coyotes with hostile actions, such as yelling and throwing objects at them. While there is some scientific basis for including an organized hazing regime as one component of a comprehensive urban-coyote management plan, these interest groups have been successful in convincing many local authorities that a public hazing regime is, aside from removing attractants, the only acceptable approach for addressing aggressive or habituated coyotes and that any lethal measures are not only inhumane but ineffective, as a matter of science. However, there is no mainstream scientific literature that supports their view. To the contrary, the only scientific literature on the subject casts doubt on the efficacy of hazing, at least as a long-term solution. Nevertheless, many municipalities have accepted these objectively biased groups’ representations as scientifically valid with little question and have adopted coyote policies based on such representations, without the usual hyper concern for public safety and liability that municipalities are famous for. This paper puts the urban-coyote management plans pushed by interest groups, like the Humane Society of the United States and Project Coyote, under the microscope to evaluate their scientific pedigree to show how widespread their campaign of misinformation reaches.

Among the many topics discussed under the broad category of urban ecology, few are as contentious as the management of unowned free-roaming cats. Like any public policy, the policies intended to effectively manage the population of these cats must, in addition to meeting other criteria (e.g., reflect broad public interest, economic feasibility, etc.), be based on sound science. Although many communities across the country have implemented programs based on the trap-neuter-return (TNR) method of managing “feral” cats, such efforts are often met with significant opposition by those claiming to have science on their side. However, this review of one of the most-often cited research papers on the subject reveals a number of significant shortcomings that undermine such claims. Public policy justified by such work is likely to prove costly and ineffective, and will very likely increase any legitimate threats unowned free-roaming cats pose to wildlife, the environment, and public health.

In many cities across the United States, incidences of coyote encounters (Canis latrans) and human-coyote conflicts are rising. This is especially true for cities in Southern California, where conflicts including pet attacks have been recorded since the 1960s. The only coyote-related human fatality in the United States occurred in Southern California in 1981 and, although no fatal attacks have occurred since, coyote bites to humans are still occurring. Coyote attacks on pets appear to be common in Southern California; however, data are lacking in this area of human-coyote conflicts. This paper examines data from multiple sources that record human-coyote conflicts in Southern California. Coyote reports have been more frequently received by the entities involved in this analysis as their recording time progresses, with data from 243 cities and unincorporated areas suggesting that the majority of reports (68%) are related to non-conflict events. Conflicts were significantly higher in the pup-rearing season compared to the breeding season. There appears to be spatial clustering of coyote reports from Los Angeles County; however, complex analysis is needed to determine the relationship between frequency of complaints and land use in all of the counties to help determine what is driving human-coyote conflicts in Southern California.

DRC-1339 (CPTH, 3-chloro-p-tolouidine) is an avicide registered to reduce local populations of selected bird species at feedlots, dairies, and staging areas near rice fields, and to prevent livestock depredation. Additionally, two registrations are specifically for controlling gulls and pigeons. U.S. Department of Agriculture Wildlife Services personnel historically have used a variety of methods to estimate take, including counting carcasses and quantifying reduction in bird activity. Because this avicide is slow-acting and birds usually succumb away from the bait site, carcass recovery provides poor estimates of take. Because of natural variability in bird numbers and activity, quantifying reductions in bird activity is also a poor gauge of efficacy. Scientists at the U.S. Department of Agriculture APHIS Wildlife Services National Wildlife Research Center developed and continue to adapt and refine a model using a bioenergetics approach to estimate consumption and the resulting mortality from DRC-1339 bait consumption. The model estimates take for the major baits used under the feedlot and staging area labels for European starlings, blackbirds, brown-headed cowbirds, and common grackles. Consumption of homogeneous baits (rice, cracked corn, fat pellets) has been well characterized, and take (i.e., mortality) is accurately predicted in the model. However, predictions of take when french fries were used as a bait for controlling starlings at feedlots in Washington State were less accurate. Thus, we modified the model to capture the feeding behavior of birds using this highly heterogeneous bait by removing the dependence on bait mass and simplifying the calculation of dose ingested. The modified model calculates dose directly from the amount of DRC-1339 per calorie consumed instead of from the DRC-1339 concentration per bait consumed. In this paper, we compare estimates of take based on french fry bait mass distributions and caloric contents determined for five different french fry bait types.

Tests were conducted using 0.05% warfarin baits which were put into polietilinized paper bags with corn oil as attractants, in order to control cotton rats (Sigmodon hispidus major) through-out 4,000 ha. of crops in the Sinaloa State. Both the effectiveness of the warfarin bait and the security and efficiency of the handling of the polietilinized paper bags was demonstrated. Furthermore, the tests showed that there were economic advantages in using the warfarin baits instead of the zinc phosphide baits; to the extent of a 46.67% saving in the control expenses.

Hawai‘i has no native parrots (Psittacidae), but at least two species of this family have naturalized on the island of Maui, the result of accidental or deliberate releases of pet birds. A breeding pair of mitred conures was illegally released in approximately 1986 on the north shore of Maui. At its peak, a population of over 150 birds was documented, demonstrating that conures in Hawai‘i can be highly productive in the wild. These non-native birds pose a threat to Hawaiian ecosystems, agricultural productivity, and quality of life. They are highly adaptable, reproduce rapidly, eat a variety of fruits and seeds, are extremely loud, can carry viral and bacterial diseases, and may compete with native seabirds for cliffside burrows. Of particular concern is the conures’ ability to pass viable seed of highly invasive species, including Miconia calvescens, a tree which is found near the conures’ roosting/breeding areas. Information from the conures’ native range in South America suggests these birds can become established at elevations in excess of 3,000 meters, underscoring the potential for spreading invasive weeds into intact, native forests, and high value watersheds at upper elevations. In response to threats posed by mitred conures, a variety of strategies had been explored to reduce or eliminate the Maui population, including bait stations, live bird lures, mist nets, rappelling to locate roosts, and audio playbacks of conure vocalizations. None of these approaches proved successful. Shooting individual birds was deemed the most appropriate alternative and has been highly effective: approximately 20 birds remain in the wild. This paper highlights historic efforts, lessons learned, and the value of a cooperative interagency and community-based approach for removal of a non-native flock of mitred conures.

Feral nutria were established near Blackwater National Wildlife Refuge (BNWR) in Dorchester County Maryland in 1943 after a failed attempt to create a fur industry. As the population expanded in number and distribution, natural resource managers began to notice an accelerating trend in wetland loss in the areas most heavily infested by nutria. By the late 1980s, an estimated 35,000 nutria occupied BNWR, which had seen approximately 5,000 acres of emergent marsh converted to shallow open water habitats and mudflats. Exclusion studies in the 1990s demonstrated a direct link between nutria and marsh loss, and by 2000 officials had procured funding to initiate an eradication feasibility study. This paper provides a historical overview of the eradication campaign that has been underway since 2002. The Chesapeake Bay Nutria Eradication Project (CBNEP) is a cooperative partnership between the U.S. Fish and Wildlife Service, USDA Wildlife Services program, and numerous state and non-governmental organizations. The CBNEP employs an adaptive management strategy utilizing systematic trapping carried out by salaried wildlife specialists to eliminate nutria from infested watersheds. We present a phased approach that allows us to continually expand the eradication zone and maintain nutria-free areas with a relatively small staff. Through an active research and development program, we have innovated new tools and techniques for trapping and detecting nutria including: floating trap sets, attractants, decoys, remote triggered cameras, detection platforms, hair snares, and Judas nutria. To date, we have reduced nutria populations to near-zero densities across 250,000 acres of emergent marsh. Based on extensive surveys, remaining populations should be removed by the end of 2014. Following a 2-year verification/biosecurity protocol, we hope to have nutria eradicated from the Delmarva Peninsula by 2017.

The invasive Burmese python is a large constrictor snake that is now well established in south Florida. This invasive predator could have major detrimental impacts to native wildlife populations and is a perceived threat to human health and safety. Finding and removing this elusive predator in vast Everglades habitats of wet sawgrass prairies with interspersed hardwood hammocks poses many challenges for biologists and land managers in south Florida, and no single solution is likely to prevail. In ongoing research, we are exploring opportunities to improve detection of this cryptic species using such diverse approaches as environmental DNA, trained detector dogs, and thermal infrared imagery. In this paper we update the status of these efforts. Other research, using captive pythons in outdoor pens at our facility in Gainesville, has resulted in the development of a newly-patented live trap that is specific to large snakes. We are currently testing and evaluating techniques to complement this new trap design for effective python removal in concert with improved detection tools.

Anthraquinone is an effective chemical seed repellent that protects newly planted crops from depredation by granivorous birds. We are experimenting with foliar applications of 9,10-anthraquinone (AQ) to reduce blackbird (Icteridae) damage to ripening sunflower. Sunflower heads generally turn downward as the achenes mature. With the methods currently available for spraying crops, application of AQ directly onto sunflower achenes is nearly impossible. Blackbirds sometimes remove sunflower bracts prior to eating achenes. Thus, getting AQ droplets directly on the achenes may not be necessary, and spraying the heads should expose blackbirds to AQ as they remove bracts. Studies using caged red-winged blackbirds showed that AQ sprayed onto the backs of sunflower heads reduced damage. However, field trials using fixed-wing aerial sprayers and ground sprayers produced inconclusive results. We are currently experimenting with methods to increase spray coverage of AQ while simultaneously attempting to reduce AQ contamination of achenes, thus reducing the likelihood of having to establish food tolerance limits for this comparatively long-lived compound. In this paper, we summarize results from several AQ studies and speculate on when a repellent might be available for sunflower producers.

Vertebrate pest management in Australia continues to evolve in response to land use changes, shifting community attitudes, and advancing technologies. The increasing demands and complexity of this profession requires employees with expertise in a broad range of disciplines. The Australian Pest Animal Strategy (APAS) recommends that best practice management of vertebrate pests should focus on reducing damage due to pests rather than the number of individual animals, using a strategic and integrated approach that incorporates the best available knowledge, tools, and skills. To help achieve this, Australia’s vertebrate pest management training qualifications under the national Vocational and Education Training system are being updated to align with the APAS. Industry engagement and consultation during the scoping phase of this project has highlighted a number of reasons why people who work in pest management are not undertaking training to obtain nationally recognised qualifications. Barriers to formal education include employers who are unwilling to release staff for periods of training; a lack of available training courses and skilled trainers in the industry, especially in rural and regional areas; workers with university qualifications who lack practical field skills; workers who are employed on short-term contracts with no secure career path; and a preference for competency-based short courses for professional development. This paper explains the motivation behind Australia’s qualifications and training review and how the industry proposes to overcome some of the problems with current training programs. These issues are not unique to Australia, and we also explore how the United States is facing similar challenges in addressing the continuing education needs of vertebrate pest management professionals.

Individual perceptions of free-roaming cats can vary from “voracious predators of small birds and mammals” to “cherished and beloved companion animals.” This paper focused on the influence of situational variables (e.g., experiences with outdoor cats), cognitive variables (e.g., attitudes toward cats and cat management), and demographic variables (e.g., gender, cat ownership) on perceptions of the risks posed by free-roaming cats to the ecosystem and the benefits that cats provide to people. In addition, we analyzed the potential role that risk and benefit perceptions play in mediating the relationship between attitudes toward outdoor cats and tolerance for the future cat population. We conducted an 11-item written survey of 474 undergraduate students enrolled in two introductory ecology courses. There were significant differences in perceived risks and benefits of cats between cat owners and nonowners and cat feeders (people who fed free-roaming cats) and non-feeders. Perceptions of the current cat population, experiences with cats and attitudes toward cats predicted both perceptions of risks to the ecosystem and benefits to people. The relationship between attitudes and tolerance was mediated by individual perceptions of benefits to people from free-roaming cats. Experience with free-roaming cats, attitudes toward cats, affection for cats, and demographic variables predicted individual risk perceptions. These perceptions, in turn, influenced support for future cat population levels and should therefore be addressed in management campaigns aimed at reducing the outdoor population of free-roaming cats.

Outbreaks of foodborne illness associated with the consumption of leafy green produce from California and across the United States have heightened the need to identify vertebrate sources of these microbial hazards. Concern has focused on wildlife species that have direct access to the produce production environment and irrigation water supplies. Recent fecal surveys of California wildlife, feral animals, and livestock and companion animals are allowing regulators to compare the food safety risks of such pathogens as E. coli O157:H7 and Salmonella from these various animal species. In order to make valid food safety risk comparisons between wildlife, livestock, and companion animals, a variety of methodological and epidemiological issues need to be addressed in order to avoid substantial biases. For example, the amount of feces tested per animal can vary up to a 1000-fold, substantially biasing the probability of testing positive for large fecal contributors (e.g., cattle) compared to smaller wildlife (e.g., deer mice). Many wildlife species intrude and forage as a group in fields of produce, which can lead to in-field defecation, substantially, elevating the risk of microbial contamination compared to many larger animal species that do not have direct access to produce fields due to fencing. This paper highlights the technical challenges of making valid quantitative comparisons of microbial food safety risks from wildlife compared to other domestic animals.

Principles contained in the 1993 publication “Managing Vertebrate Pests: Principles & Strategies” were developed during a review of past and current pest management practices. They were used to guide the development of a series of management guidelines for our major vertebrate pests – feral pigs, house mice, European rabbits, red fox, feral pigs, feral horses, wild dogs, and carp. The principles have been constantly refined through subsequent on ground experience in working with stakeholders to implement best practice management programs for pest animals. In this paper, we present what we now consider the seven principles that underpin best practice management of pest animals. They are: 1. A pest is human construct. 2. All key stakeholders need to be actively engaged and consulted. 3. Rarely can pests be eradicated. 4. Most pest management needs to focus on the outcome, reduction in damage, not just killing pests. 5. A whole-system approach is required for managing pest damage. 6. Most pest management occurs in ecosystems in which our knowledge is imperfect. 7. An effective monitoring and evaluation strategy is essential for all management interventions. Together, the principles comprise the strategic approach to pest management. We explain the rationale behind these principles and illustrate them with examples.

Fox squirrels are an emerging urban, suburban, and agricultural vertebrate pest in California. They cause a diversity of damage to vegetation and property. Multiple introductions of fox squirrels into California have led to a rapid expansion of their range in the state. Fox squirrels at the University of California, Davis increased from none to an estimated 1,609 between 2001 and 2009. Damage due to the dense population of fox squirrels is increasing. There are several population control options available, but social considerations may limit the viable options to non-lethal methods. This paper provides an overview of the impacts of the introduced fox squirrel in California and on the University of California, Davis campus.

Vertebrate pest animal control and research is a relatively small area of activity within the agricultural and environmental fields. However, it is critical for agricultural productivity and biodiversity. There is much to be gained by having vertebrate pest controllers and researchers collaborating worldwide. The critical mass achieved through collaboration will result in faster registration of new products, better implementation of new methods, and increased skills within vertebrate pest units. The plain fact is that vertebrate pest control involves the killing of animals, sometimes those with iconic status. Having the public, or even other scientists, recognize the need for animal control can be complicated because of people’s natural concern for the welfare of animals. Those involved in the sector must become better advocates for the agricultural and biodiversity benefits of animal control. Although it is very uncomfortable for many scientists, they must face up to community dialogue in all its modern forms, and not simply rely on scientific reports and published papers speaking for themselves.

Nonnative feral ungulates have both direct and indirect impacts on native ecosystems. Hawai`i is particularly susceptible to biological invasions, as the islands have evolved in extreme geographic isolation. In this paper we explore the ecological impacts of nonnative feral goats (Capra hircus) in the Hawaiian Islands, including both the current state of knowledge and future research directions to address knowledge gaps. Understanding how invasive vertebrates impact island ecosystems is important as it provides an informed context for developing contemporary solutions to pressing management problems. Current knowledge gaps, such as the behavioral ecology of goats and their impacts on specific plant species and communities, limit the effectiveness of ecological restoration and conservation in Hawai`i. Emerging technologies in wildlife tracking and remote sensing will enable a greatly improved understanding of the behavior and ecological impacts of these nonnative animals in what is already a highly degraded ecosystem.

There is a need in New Zealand for a new, more advanced generation of toxins to minimize the impact of invasive animals. A new pest control agent, para-aminopropiophenone (PAPP), represents a lead candidate presently undergoing registration for the humane control of stoats and feral cats. It exhibits low toxicity to most bird species, no secondary poisoning risk, and has a simple and highly effective antidote. PAPP induces methemoglobinemia (MtHb), which acts to prevent oxygen from binding to red blood cells. This reduces oxygen supply to the brain, causing animals to become lethargic, sleepy, and unconscious prior to eventual death in 1 to 2 hours. Despite such promise, to date no previous study has comprehensively examined the effect of modifying the structure of PAPP on MtHb induction. Using PAPP as a platform, this paper describes the design, synthesis, and bioevaluation of PAPP-like red blood cell toxins. The impacts of introducing groups of varying electronic nature at different positions on the PAPP molecule are presently being evaluated. Analogues are synthesized and their MtHb-inducing properties determined using an in vitro assay to establish a formal structure-activity profile. In vivo evaluation in rats is used to assess both their acute toxicity and humaneness of potential candidates. Structure-activity profiles are discussed with the objective of optimizing the bioavailability and potency of PAPP-like compounds to target, high priority pests, particularly rodents.

Strychnine has recently been made available in Canada under an emergency registration program for the control of Richardson’s ground squirrels. From 2007 to 2009, we tested the control efficacy of this poison using >1-year-old and newly produced strychnine on hulless oats, canary seed, and alfalfa pellets. Newly produced 2% liquid strychnine, mixed with hulless oats to formulate 0.4% strychnine freshly mixed baits, controlled ≥70% of adult and juvenile ground squirrels in spring and summer. Other types of strychnine baits were not as reliable from one season to the other. At 0.2% concentration, strychnine-treated oats were relatively inefficient. When >1 year old, the control efficacy of strychnine baits dropped significantly. Independent of the age of the product, strychnine killed non-target animals. This paper recommends a series of measures to ensure quality control and greater selectivity.

At least 137 species of common bamboos of India and rest of Asia seed synchronously at long and supra-annual intervals. These include species belonging to the genera Phyllostachys, Arundinaria, Bambusa, Dendrocalamus, Gigantochloapus, Malocanna, Guadua, Nechouzeaua, Ochlandra, and Thyrostachys. The enormous quantity of seeds shed by these bamboos affect the population dynamics of several vertebrates, including mostly birds, rodents, and wild pigs. The rodents, as generalist seed predators, exhibit a very complex response to the sudden spurt in the availability of nutritious bamboo seeds. In North-east India, the popular saying and belief “when bamboo flowers, famine follows” refers to the phenomenon of gregarious bamboo flowering, massive seed fall, and irruptions in rodent populations, which, after exhausting the bamboo seeds, invade and devour the entire crop fields and stored foods, leading to famine. Such events have been occurring approximately every 40 - 45 years since 1880, the latest being 2005 - 2007 sans any famine. Although 14 species of rodents occur in North-east India, until now there is no strong evidence to identify the species exhibiting population outbreaks. The species suspected to irrupt are Rattus rattus, R. r. brunneusculus, R. bowersi, R. niviventer, and Canomys badius. Similar irruptions of rodent populations in South America has been documented since 1800. These eruptions, termed ratadas, were seen in Oligoryzomys longicaudatus and Abothrix longipilis consequent to flowering of Chusquea quilla. Comparable density increases are seen consequent to masting in trees other than bamboo. Although the mechanism of seed masting is attributed to several hypotheses, predation satiation is the most accepted theory. In this paper, rodent response to masting is discussed in relation to this theory. The non-occurrence of famine in North-east India consequent to 2005-2007 bamboo flowering is mainly due to the effective strategies formulated by the government of India to prevent population buildup of rodents. This seems to be a fine instance of prophylactic approach to rodent management in large areas encompassing several states.

More than 300 migratory bird species in Oregon have the potential to nest in highway rights-of-way or on bridges. Because these species are protected under the Migratory Bird Treaty Act (MBTA) and there are no incidental take permits, Oregon Department of Transportation (ODOT) projects may be impeded by nesting birds. In 2006, ODOT contacted USDA Wildlife Services to assist with MBTA compliance. This paper describes the unique nature of the inter-governmental agreement and the success it has brought both agencies.

Predation effects have been studied since the early days of wildlife management, with the goal of wildlife managers to balance wildlife populations with available habitat and management objectives. Still, research and public debate focuses on the degree to which vegetative carrying capacity (K) affects prey and the degree to which predation management could benefit prey species. K, to this point, has not generally considered the secondary effects that predators have on prey habitat availability. When setting wildlife management objectives, the relationship of predation impacts (i.e., factors that may cause mortality in a given species) to prey and available habitat and habitat availability must be examined carefully and understood. This paper discusses classic predator-prey relationships and the potential effects of secondary predation on prey. Managers must consider these effects and relationships to determine if, when, and how to implement an effective wildlife enhancement or predation management strategy.

Feral swine may harbor the causative agents of important foodborne diseases such as brucellosis, cryptosporidiosis, salmonellosis, and trichinosis. We described recently the isolation of Escherichia coli O157:H7 from feral swine in the central California coast during an investigation of a nationwide outbreak associated with consumption of contaminated fresh baby spinach. Additionally, the foodborne pathogen Campylobacter was found in tissues and feces from the same population of feral swine. Feral swine are the most abundant free-roaming ungulate in the United States, and their range in California continues to expand, with the highest numbers reported on the central coast. The expansion of feral swine in mainland California and concomitant damage to agriculture and public health underscore the need for mitigation strategies. A number of lethal and non-lethal methods for feral swine management have been described, including hunting, depredation, trapping, and exclusion such as fencing. This paper reviews current concerns relating to food safety and feral swine. The advantages and potential pitfalls of mitigation strategies to reduce the risk of contamination of raw vegetable commodities by free-roaming feral swine are discussed.

Gray wolf populations have exceeded anticipated recovery levels since they were first reintroduced to central Idaho in 1995. Although wolf predation on livestock is a relatively minor issue to the livestock industry as a whole, it can be a serious problem for some individual livestock producers who graze their stock in occupied wolf habitat. This paper compares Idaho population estimates for gray wolves with the available information on numbers of livestock killed by wolves in order to estimate numbers of livestock killed per wolf. This information is compared with similar analyses for other species most commonly implicated as predators of livestock in Idaho (coyotes, black bears, and mountain lions). Population estimates for coyotes, black bears, and mountain lions are based on review of available scientific literature and analyses in environmental assessments prepared by Wildlife Services, as well as estimates from the Idaho Department of Fish and Game. Wolf population estimates are based primarily on monitoring information provided by the Idaho Department of Fish and Game and the Nez Perce Tribe. Estimates of numbers of livestock killed by wolves, coyotes, black bears, and mountain lions are based on survey data compiled by the National Agricultural Statistics Service. Rationale for use of various data sets is provided, and limitations of the data are discussed. This analysis suggests that individual wolves are much more likely to prey on livestock than are individuals of any other predator species in Idaho.

Many fish stocks targeted by fishermen are also a primary food source of marine mammals. Normally this would be viewed as competition for a common resource. With the passage of the Marine Mammal Protection Act (MMPA) in 1972, marine mammals are protected which has aided in the recovery of numerous species. Along the West Coast, the MMPA has been highly successful in the recovery of most stocks of California sea lions and Pacific harbor seals, and it has resulted in more frequent interactions with commercial and recreational fishermen, causing damage to fishing gear and loss of catch. Non-lethal methods to eliminate or reduce pinniped predation have been unsuccessful. This paper summarizes the issue of marine mammal depredation in general, examines some of the economic damages, and discusses efforts to minimize these interactions.

The concepts of “integrated control” and “integrated pest management” (IPM) were devised by entomologists, but they proved relevant to the monitoring and control of virtually any agricultural pest (i.e., weeds, fungi, vertebrates). Within IPM, economic threshold characterized pest densities that would have negative impacts and economic injury level characterized amounts of predicted crop injury (destruction) that would allow recovery of potential pest-control costs. Approximately 150 species or groups of vertebrates have been documented to pose human health/safety risks or to cause agricultural, natural resource, and property losses in North America. Rodent (e.g., mice, rats, ground squirrels) and bird (e.g., blackbirds, gulls, cormorants) populations are the most frequently cited species/groups of vertebrates linked with IPM. Uncertainty characterizes IPM applications to control damage by these species/groups. Uncertainty is a measure of variance, which occurs due to the myriad of biological, crop, economic, meteorological, pesticide, production, seasonal, and soil unknowns that impact IPM programs. Six uncertainty-reduction techniques are commonly used by economists: 1) worst-/best-case scenario, 2) contrived scenarios, 3) decision tree analysis, 4) sensitivity analysis, 5) Monte Carlo simulation, and 6) systematic projections. This paper reviews key IPM literature, especially economic literature, and discusses techniques that can reduce the economic uncertainty of using IPM programs with vertebrates.

The term “vaccine” has traditionally been associated with establishing immunity (antibodies) to a disease. This immunity is usually developed following administration of killed microorganisms. Disease vaccines typically require 1 to 3 injections, depending on the antigen design and efficacy of the vaccine. The effectiveness of the disease vaccine depends on the immune response developed by the host following exposure to the disease organism. The immunocontraceptive vaccine GonaCon™ is designed to produce immunity to the “self” hormone (GnRH), which is essential to reproductive activity in the mammal. Antibodies to GnRH reduce its biological activity resulting in infertility of both sexes. GonaCon™’s effectiveness as a single-injection immunocontraceptive wildlife vaccine depends on 4 factors. The first is the use of a large foreign mollusk protein in the GnRH conjugate. Second is the design of mollusk/GnRH protein conjugate that presents the GnRH antigen in a repetitious fashion. This design mimics the “danger signal” found in bacterial pathogens to which the animal has been previously exposed. Third is the addition to the vaccine of micrograms of Mycobacterium avium, which is ubiquitous in the environment and activates memory cells. The fourth factor is use of a water-in-oil emulsion, which provides a depot at the injection site, allowing a slow release of the vaccine. With this formulation, the vaccine is presented to the body as a “chronic infection”, even though it is not infectious. The granuloma that normally develops at the injection site plays a prime role in the host’s defense against this “chronic infection”. A WHO report on the use of the alum adjuvant in human vaccines states that “development of a small granuloma is inevitable with vaccines adjuvanted with aluminum, and is to be considered necessary to the efficacy of the adjuvant.” Researching GonaCon™ for use in companion animals, NWRC has looked at many different adjuvants intended to reduce the injection site reaction while at the same time retaining an effective vaccine. This paper reports on the role of the adjuvant and the injection site on the effectiveness of the vaccine.