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Approximately 60% of diseases causing pathogenic illness in humans originate in animals. Emergence and re-emergence of zoonotic and vector-borne diseases pose considerable public health, environmental, and economic impacts in the U.S. There are over 250 urban areas in the U.S. with populations > 100,000. These densely populated centers, with concomitant development of natural areas, greenbelts, and walking trails, are viewed to exacerbate the potential for human-wildlife, pet-wildlife, and pet-human interactions leading to greater risks of zoonotic disease transmission. Wildlife rabies, West Nile virus (WNV), and bovine tuberculosis (bTB) offer illustrations of potential impacts from zoo noses in urban areas. Prevention of wildlife variants of the rabies virus are estimated to cost > $250 million annually; probable transmission in urban environments can involve direct human exposure to rabid coyotes (Canis latrans), raccoons (Procyon lotor), skunks (Mephitis mephitis, Spilogale putoris), and red foxes (Vulpes vulpes) or indirect exposure to the virus via pet-wildlife contacts with these animals. West Nile virus is a mosquito-borne illness that has killed >785 people in the U.S.; hospitalization costs associated with the outbreak of this disease in Colorado's densely populated Front Range averaged $33,980/admitted patient. The re-emergence of bovine tuberculosis (bTB) in cattle (Bovidae spp.) of Michigan's northern Lower Peninsula has resulted in a loss of the State's "TB-accredited free" status costing the state an estimated $22-74 million in five years. Monitoring, preventing, and treating zoonotic diseases pose new challenges for public health, veterinary, and wildlife professionals, with densely populated urban environments likely to exacerbate transmission and impacts.

The Wildlife Master (WM) Program in Colorado was modeled after the highly successful Master Gardener volunteer program. In 10 highly populated suburban counties with large rural areas surrounding the Denver Metro Area, Colorado State University (CSU) Cooperative Extension Natural Resources agents train, supervise and manage these volunteers in the identification, referral, and resolution of wildlife damage issues. High quality, research-based training is provided by university faculty and other professionals in public health, animal damage control, wildlife management and animal behavior. Inquiries are responded to mainly via telephone. Calls by concerned residents are forwarded to WMs who provide general information about human-wildlife conflicts and possible ways to resolve complaints. Each volunteer serves a minimum of 14 days on phone duty annually, calling in from a remote location to a voice mail system from which phone messages can be conveniently retrieved. Response time per call is generally less than 24 hours. During 2004, more than 2,000 phone calls, e-mail messages and walk-in requests for assistance were fielded by 100 cooperative extension WMs. Calls fielded by volunteers in one county increased five-fold during the past five years, from 100 calls to over 500 calls annually. Valued at the rate of approximately $18.00 per volunteer hour, the leveraged value of each WM was about $450 in 2005, based on 25 hours of service and training. The estimated value of the program to Colorado in 2004 was over $45,000 of in-kind service, or about one full-time equivalent faculty member. This paper describes components of Colorado' s WM Program, with guides to the set-up of similar programs in other states.

A comprehensive cost model of wildlife rabies is presented. A total of 11 factors were viewed to comprise the diverse agricultural, insurance, medical, and veterinary expenses associated with rabies (i.e., pet vaccinations, livestock vaccinations, pet replacements, livestock replacements, pre-exposure prophylaxis for humans, post-exposure prophylaxis for humans, adverse medical reactions, animal control activities, public health charges, quarantine costs, and human death settlements). These factor costs form the basis of potential savings to be gained from rabies control activities. Irrespective of incidence, per unit costs and ranges were found to be greatest for livestock replacement, post-exposure prophylaxis, adverse medical reactions, and human death settlements, with substantial costs of adverse medical reactions and human deaths occurring infrequently but due to potential insurance or litigation claims. Empirical studies are needed to document the incidence of these factors during pre-epizootic, epizootic, and post-epizootic phases of wildlife rabies.

Economic uncertainty surrounds the distribution of Raboral V-RG7 as an oral rabies vaccine (ORV) bait for the containment or elimination of raccoon-variant rabies in the United States. This paper describes a costs-savings model of ORV. lt also describes Excel XP7 code that was prepared to compute potential net savings (NS) and benefit-cost ratios (BCRs) associated with Raboral V-RG7 bait distributions. Currently, baits and bait distributions are relatively expensive; individual baits are produced at a cost of $1.27 for federal use and typically dispensed at >75 baits/km2. Distribution is estimated at $8.62/km2, $15.80/km2, and $33.30/km2 for fixed-winged (FW), ground (Gnd), and rotary-winged (RW) applications, respectively. Although many assumptions are required, iterative runs of the code allow plotting NS and BCR response surfaces for diverse scenarios based on 6 ORV variables: area (km2), bait-price (US$/vaccine bait), bait-density (#/km2), application frequency (n), mode-of-delivery [$US for % fixed-winged (FW), % rotary-winged (RW), and % ground-dispensed (Gnd)], and effectiveness(% seropositive titer conversion). Using a raccoon-rabies-epizootic-containment scenario for parts of Pennsylvania and a modest epizootic cost estimate of $40 million, the greatest NS ($6.4 to 38.4 million) and BCR (2.85 to 25.76) indices occurred for a one-time bait distribution involving FW aircraft over a fourth of the state with a $0.90/bait price. As expected, greater reliance on the more expensive RW and Gnd modes of bait distribution compared to FW aircraft, coupled with higher bait prices and higher bait densities, decreased NS and BCR indices. The utility of the approach to economic forecasting and decision making of ORV effects are discussed.

Sterner (In press) described the use of a priori, theoretical analyses of crop/resource savings and benefit:cost ratios as a way of making intervention decisions in wildlife damage management. Iterative (1-variable-changed-at-a-time) calculations of these economic indices were computed for the use of zinc phosphide baits to control vole (Microtus spp.) populations in alfalfa (Medicago sativa). Results showed that indices displayed transitive effects -- greater net savings and benefit:cost ratios were related to larger field-size, crop-damage and bait-effectiveness variables, but smaller bait-application fees. Ratios varied between 0.40 and 6.45, with -5-10% vole-caused damage required to produce returns on investments equal to the costs of control (benefit:cost ratio = 1.0). This paper presents the detailed Lotus® 1-2-3®, 9.5 code used to derive the results of Sterner (In press). Adaptation of the code to the study of other wildlife damage management problems is straightforward.

Public and governmental concerns about the health, safety, and environmental impacts of pesticides have led to increased regulatory requirements to determine the hazards and risks associated with their manufacture, distribution, and use. Vertebrate pesticides are regulated by the U.S. Environmental Protection Agency (EPA) under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), as amended. Much of the data required for registration of these pesticides will be generated by commercial testing laboratories under contract to the product registrants or sponsors. In this paper, we address aspects of the contract research process including: 1) an overview of FIFRA requirements, 2) the nature of the contract research process, 3) guidelines for setting up and administering a contract for this type of work, and 4) several case studies to illustrate some of the "pitfalls" that may be encountered. The information presented is based on the collective experience of the authors' involvement with 49 contracted studies over a three-year period.

The U.S. Department of Agriculture (USDA), Animal Plant and Health Inspection Service (APHIS) maintains six federal registrations for zinc phosphide (Zn3P2); three of these address the control of eight rodent species using steam-rolled oats (SRO) or wheat grains in diverse applications. Optimal foraging theory (OFT) and "particle dose analysis" (PDA) afford predictions relevant to the efficacy, acceptance, bait shyness, and non-target hazards of these Zn3P2 baits. For PDA, numbers of SRO groats or whole wheat grains associated with acute oral median lethal (LD50) or approximate lethal (ALD) doses of Zn3P2 were compared among nine target rodent and eleven non-target avian species. Key outcomes were: 1) mean (±S.D.) SRO groats and wheat grains weighed 23 (±9) and 18 (±9) mg [assumed to carry ≈0.46 (2.0%) and ≈0.33 (1.82 %) mg Zn3P2, respectively; 2) published acute oral LD50 values for the target rodents ranged between 16.2 and 18.0 mg/kg, with a 42.0 mg/kg ALD cited for the white-footed mouse (Peromyscus maniculatus); 3) estimated minimum-maximum number of SRO groats and wheat grains needed for ingestion of the LD50/ALD doses by target species were 1.6 to 39.1 and 1.7 to 3.8, respectively; and 4) estimated minimum-maximum number of SRO groats and wheat grains associated with primary LD50/ALD hazards to nontarget avian species were 1.3 to 175.8 and 1.8 to 245.1, respectively. Theoretical implications of OFT and PDA to efficacy, acceptance, bait shyness, and specificity of Zn3P2 baits in rodent control are provided; the potential effects of food-handling time, bait-search time, predator density, social-dominance hierarchy, food-intake pattern, and bait-distribution pattern are discussed.

The use of LiCl-treated baits and carcasses has been advocated as a means of controlling coyote predation on sheep through a process known as "aversive conditioning or taste aversion." While some investigators have made well publicized claims of damage reduction through the use of LiCl on sheep ranges, other researchers have experienced difficulty establishing prey aversion in captive coyotes. The conflicting results suggest a need for extensive, carefully controlled research in both pen and field situations before valid conclusions can be reached regarding aversive conditioning as a depredations control method.