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In 2001, Marin County, California, replaced its USDA Wildlife Services (WS) cooperative predator damage management program with a county-run program that emphasized non-lethal methods for preventing and controlling coyote predation on sheep. This new “Livestock Protection Program” cost-shared with livestock producers’ efforts to improve fencing, obtain and maintain guard animals, and other such non-lethal methods, and initially it compensated producers for documented losses to predators. We surveyed sheep producers in Marin County in an effort to review the program over the past 15 years, evaluating the program in relation to livestock production, economics, predation management, and other measures of producer satisfaction. Lack of standardized data collection during the current program complicates its evaluation; however, from available information, we conclude the number of sheep and lambs are being produced in Marin County has continued to decline; some producers left the sheep business and other who remain graze less acreage with smaller flocks; predation by coyotes remains a high concern to producers; and most producers are dissatisfied with the Livestock Protection Program.

Beginning with the developing pattern of urban and suburban coyotes attacking humans in southern California in the late 1970s, we have gathered information on such incidents in an effort to better understand the causes of such changes in coyote behavior, as well as to develop strategies that can reduce the incidence of such attacks. Here, we update information from our knowledge of conflicts between humans and coyotes occurring largely in urban and suburban environments in the United States and Canada during the past 30 years. This problem emerged in states beyond California and in Canadian provinces in the 1990s, and it appears to be growing. We have documented 367 attacks on humans by coyotes from 1977 through 2015, of which 165 occurred in California. Of 348 total victims of coyote attack, 209 (60%) were adults, and 139 (40%) were children (age ≤10 years). Children (especially toddlers) are at greater risk of serious injury. Attacks demonstrate a seasonal pattern, with more occurring during the coyote breeding and pup-rearing season (March through August) than September through February. We reiterate management recommendations that, when enacted, have been demonstrated to effectively reduce risk of coyote attack in urban and suburban environments, and we note limitations of non-injurious hazing programs. We note an apparent growing incidence of coyote attack on pets, an issue that we believe will drive coyote management policy at the local and state levels.

The book Prevention and Control of Wildlife Damage (PCWD) is the award-winning and leading reference in the field. Over 13,000 copies of the 4th edition were sold, and we conservatively estimate that it saves $210 million in resources and $220 million in labor annually. Emerging issues and changes in the field, however, have precipitated the need for a new 5th edition of PCWD. Six editors and over 120 authors are working to create the next edition, which will include 36 new and 77 revised chapters. We anticipate that the 5th edition of PCWD and derivative products will be available as a two-volume book, CD, website, e-book, and mobile app, starting in 2015.

Conflicts between urban coyotes and humans have increased in recent years, particularly in the West. These include aggression and attacks on children, adults, and on pets; and damage to drip irrigation systems, garden crops, and other resources. News reports and our contact with agencies have informed us of more than 110 incidents in California alone, most within the past decade, in which humans were bitten by coyotes. However, few data are available on incidents of pet loss or other human-coyote conflicts in urban habitats. We suspect many conflicts occur because of human behaviors that results in coyote habituation; we hypothesize that with informed management, most are preventable. We have developed a web site, http://www.CoyoteBytes.org, as a tool to provide science-based management recommendations to homeowners and municipal officials to reduce coyote conflicts in urban / suburban areas. In addition to providing information, the website allows individuals to voluntarily upload photos and video of urban coyotes, and to submit first-hand reports describing conflicts and encounters. The web site contains an incident map, an Internet-enabled Geographic Information Systems (webGIS) tool, allowing coyote incidents to be displayed via a dynamic mapping interface by type of incident and by progress through time. The website became functional in September 2007 and is being pilot-tested in San Diego, Orange, and Los Angeles counties, California. The information being collected concerning coyote encounters and incidents should, over time, provide a means for a more complete analysis of this problem, thereby improving our management recommendations. A better factual understanding of the dimensions of the problem, as well as impacts of various management strategies currently in use, should help reduce some of the polarized atmosphere surrounding cities’ and counties’ attempts to find appropriate solutions to these conflicts.

We field-tested the Coyote Lure Operative Device (CLOD), a bait delivery system for coyotes originally conceived by UC Davis researchers in the 1980s. Our objectives were to determine whether free-ranging coyotes would activate CLODs repeatedly when exposed to them over a 12-month period, and whether CLOD activations varied by season. We placed CLODs in pastures with a history of chronic sheep depredation at the UC Hopland Research and Extension Center in Mendocino County. Free-ranging coyotes activated the CLODs repeatedly, but more CLODs were activated during the winter months than at other times of the year. Our study suggests that the CLOD has the potential to become an important tool for managing coyote predation on livestock when used to deliver contraceptive or predacide baits.

Coyote attacks on humans and pets have increased within the past 5 years in California. We discuss documented occurrences of coyote aggression and attacks on people, using data from USDA Wildlife Services, the California Department of Fish & Game, and other sources. Forty-eight such attacks on children and adults were verified from 1998 through 2003, compared to 41 attacks during the period 1988 through 1997; most incidents occurred in Southern California near the suburban-wildland interface. Attack incidents are typically preceded by a sequence of increasingly bold coyote behaviors, including: nighttime coyote attacks on pets; sightings of coyotes in neighborhoods at night; sightings of coyotes in morning and evening; attacks on pets during daylight hours; attacks on pets on leashes and chasing of joggers and bicyclists; and finally, mid-day sightings of coyotes in and around children’s play areas. In suburban areas, coyotes can lose their fear of humans as a result of coming to rely on ample food resources including increased numbers of rabbits and rodents, household refuse, pet food, available water from ponds and landscape irrigation run-off, and even intentional feeding of coyotes by residents. The safe environment provided by a wildlife-loving general public, who rarely display aggression toward coyotes, is also thought to be a major contributing factor. The termination or reduction of predator management programs adjacent to some urban areas has also served to contribute to coyotes’ loss of fear of humans and to a dependency on resources in the suburban environment. Corrective action can be effective if implemented before coyote attacks on pets become common. However, if environmental modification and changes in human behavior toward coyotes are delayed, then removal of offending predators by traps or shooting is required in order to resolve the threat to human safety. We note the failure of various non-lethal harassment techniques to correct the problem in situations where coyotes have become habituated to human-provided food resources. Coyote attacks on humans in suburbia are preventable, but the long-term solution of this conflict requires public education, changes in residents’ behavior, and in some situations, the means to effectively remove individual offending animals.

The Coyote Lure Operative Device (CLOD) is designed to deliver a variety of substances to coyotes. Field evaluations have demonstrated free-ranging coyotes will activate CLODs, but little is known about coyote behavior when encountering the device in familiar or unfamiliar environments, an essential consideration. Captive coyotes show neophobic behaviors toward novel objects in familiar territory, while responses to scent stations in similar scenarios have been mixed. Free-ranging coyotes are more likely to investigate novel items and are more vulnerable to capture while trespassing in adjacent territories than when “at home”. We examined responses of captive coyotes toward CLODs in familiar and unfamiliar settings. We found no significant neophobic response toward CLODs with respect to territory familiarity, although captive coyotes spent significantly more time within 1 m of the device in a familiar environment. Relatively small sample sizes make broad inferences difficult, but our data suggest that territory familiarity might not be a strong factor in responses to the CLOD. However, more research is necessary.

In 1990, the California Legislature passed a law to collect a $0.50 per pound surcharge on all vertebrate pest control materials sold by county agricultural commissioners throughout the state. These monies were to be used to fund research required to maintain the state’s current vertebrate pesticide registrations, to improve existing rodenticides, and to find new materials and methods to solve California’s vertebrate pest problems. An external advisory committee, the Vertebrate Pest Control Research Advisory Committee, was established to set research priorities and recommend expenditures from this fund. To date, this program has raised more than $6.5 million to meet its objectives. We summarize the history and operation of the surcharge fund as well as the accomplishments of the program. Data on rodenticide sales throughout this program’s operation are presented. We describe the types of research funded to date, as well summarizing results of selected studies supported by this program. We also review accomplishments in education and outreach supported by this fund.

We conducted a comprehensive economic analysis of rodent control in swine production facilities. An interdisciplinary working group was assembled to identify all necessary input variables and values associated with rodent damage and control. We incorporated data from production models, scientific literature, product literature, producers and personal experience into an interactive STELLA systems model. The model generates cost-benefit analyses and predicts outcomes of various levels of control of house mice for site-specific swine confinement facilities. We developed a website on rodent control (http://rodent.swine.unl.edu/) to promote use of the model, increase producer awareness of the costs associated with house mouse damage, and provide information on integrated strategies for managing rodents. Although the model is relatively robust and comprehensive, we noted important gaps in research-based information, particularly associated with the economic impacts of rodents in disease transmission, feed contamination, food safety, quality assurance, and human dimensions. We will continue to improve the model and website as new information becomes available.

Coyote predation on the UC Hopland Research and Extension Center's research sheep has increased substantially during the last several decades, as it did for commercial sheep producers in the North Coast region. The center has evaluated a variety of lethal and nonlethal predator-control methods in an effort to find a strategy that is cost effective and practical for other producers. The most promising strategy tested was selective removal of only sheep-killing coyotes by use of the livestock protection collar, a tool that was banned in California by Proposition 4, a November 1998 ballot initiative.

An apparent increase in coyote-human conflicts, notably attacks on humans, demonstrates that such incidents are not rare in California. The authors discuss coyote attacks on 53 humans, resulting in 21 instances of human injury, over the last decade. These illustrate repeated, predictable pre-attack coyote behavior patterns. Specific changes in human environments and in human behavior that have contributed to coyote attacks are discussed. Case histories of attacks reveal contributing factors and suggest appropriate corrective and preventive actions. Padded leghold traps have been the most effective and efficient tool in removing problem coyotes and changing the behavior of coyotes to fear humans and the urban environment. Long-term solutions will require changes in human behavior. Humans must come to view large mammalian predators as a potential hazard. Increased public education is needed to improve methods of landscape management, refuse disposal, care of pets, and recognition of the need for predator management.

People encounter a great diversity of damage problems caused by wildlife, for which they need effective and timely solutions. Published materials or sources of help often are scattered, difficult to locate, and often members of the public struggle to find help in dealing with problem wildlife. The author describes three fictional scenarios, based on his experience in helping people find reputable information on solutions to wildlife damage problems. The article lists federal, state, and local agencies within California that can provide assistance and information concerning vertebrate pests; lists recent publications that are helpful sources of information; and lists organizations and professional associations that facilitate knowledge and training regarding wildlife damage management.