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Recovery of the endangered Mount Graham red squirrel (MGRS) will likely be long and challenging. Its limited habitat, isolation to Pinaleño Mountain range, and demographic characteristics restrict its ability to rebound quickly from threats that impact both the squirrel and its habitat. Currently, threats to the MGRS include habitat degradation and loss through high-severity wildfire, fire suppression activities, insect outbreaks, climate change, and human development, and predation, as well as competition with Abert’s squirrels. The most recent wildfire in 2017 impacted over 48,000 acres of already reduced habitat. A critical first step is to protect and manage the remaining population of the MGRS and its habitat. Management includes but is not limited to maintaining and improving the spruce-fir and mixed conifer biomes, while balancing the need to reduce risk of catastrophic wildfire with the needs of the squirrel. The U.S. Department of Agriculture, Animal and Plant Health Inspection Service Wildlife Services is conducting an Abert’s Squirrel Removal Project at the request of the Arizona Game and Fish Department and the U.S. Fish and Wildlife Service (USFWS), in collaboration with a team of Mount Graham red squirrel experts and managers, to reduce the number of Abert’s squirrels in historical MGRS habitat throughout the Pinaleño Mountains to assist in meeting the needs of the USFWS’ 2011 MGRS draft recovery plan. Abert’s squirrel removals are conducted monthly to minimize competition with MGRS.

Wildlife-aircraft collisions pose a serious risk to aircraft and cost civil aviation over US$1 billion worldwide annually. Habitat management within airport environments is the most important long-term component of an integrated approach to reduce the use of airfields by hazardous wildlife. Recent research has demonstrated that Canada geese avoid foraging on endophyte-infected tall fescue; consequently, this turfgrass might be useful in airfield revegetation and seeding projects. Although some research evaluating commercially available tall fescue cultivars on airfields has been conducted, additional information is needed to determine if tall fescue cultivars might be viable for airfields in various regions of the U.S. In 2007, a study was initiated to examine the establishment of currently available high-endophyte �‘turf-type’ tall fescue grasses at 9 airfields. The objectives were to: 1) determine if selected tall fescue cultivars establish on airfields across the U.S. and 2) provide airport-specific recommendations for tall fescue cultivar selection. At each airfield, 12 tall fescue cultivars were seeded into 3 replicate experimental plots in either fall of 2007 or spring of 2008. Although tall fescue cover varied among airports, most cultivars resulted in similar amounts of tall fescue cover after one or two growing seasons. This study demonstrates and identifies tall fescue cultivars that will grow successfully in the environmental conditions found on these airfields while providing airfield vegetation that is minimally attractive to wildlife hazardous to aviation.

Wildlife-aircraft collisions (wildlife strikes) pose safety risks to aircraft and cost civil aviation over $390 million annually in the USA. We reviewed published studies to summarize findings on habitat management techniques that have shown potential for wildlife strike reduction. Habitat components that may attract wildlife to airports include food, cover, water, and loafing areas. Although maintaining tall herbaceous vegetation on airfields may reduce the attractiveness of loafing and feeding sites for some species of birds such as gulls, this strategy may also increase cover and food resources for other hazardous species. Thus, optimum vegetation height management strategies require further research and may be site-specific. Replacing attractive vegetation with less palatable vegetation has also been recommended, but studies with widespread application are lacking. Removal of ornamental trees and shrubs reduces cover for deer and small mammals and nesting sites for birds while also reducing availability of perches. However, exclusion techniques are also needed for reducing the availability of artificial perches and water. Despite more than 30 years of substantive discussion on the importance of these habitat management techniques, few reliable studies of the effectiveness of these techniques have been conducted under operational airport conditions.

We evaluated bird and small mammal use of two mowed (15 to 25 cm height) and two unmowed vegetation plots (40 to 88 ha) at John F. Kennedy International Airport (JFKIA), New York, in 1998 to 1999 to determine which management strategy would best reduce wildlife use of the airport. We counted more birds per 5- minute observation period in unmowed plots than mowed plots in both 1998 (9.0 versus 7.9) and 1999 (11.7 versus 8.6). Maximum vegetation height was greater (P

During 1995 to 1997, the efficacy of early tactical management of mouse populations in a project based on grain-growing farms in Victoria, Australia was examined. Farmers modified their management practices of crops (at sowing, harvest, and land preparation), and managed habitats on the boundary of cropped land (such as fencelines) and around farm buildings. One management practice examined was the effect on mouse populations of controlling weeds along margins of crops. On sites where farmers slashed or sprayed weeds in early spring, there was a comparative reduction in the abundance of mice in late summer compared to untreated sites.

Southern California bas experienced rapid human population growth during the past 50 years. As housing continues to encroach into and abut previously undeveloped areas containing wildlife communities, conflicts between homeowners and predators have become common. Traditional methods of control (removal) of problem animals are often infeasible due to legislative constraints, local ordinances, public opinion, and environmental considerations. This necessitates developing alternative approaches to facilitate coexistence and diminish the opportunities for negative interactions. In the Defensible Space program, people are educated about local wildlife and provided animal behavior-based methods to respond to animal incursions. Though the system is not always 100% effective, it has diminished the overall number of complaints received and reduced most of the remaining complaints from panic-based to knowledge-based.

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.

Wildlife damage management has often emphasized density reduction through lethal means. In addition to facing increasing regulatory and social restrictions, this approach also faces ecological problems; density reduction without a concomitant decrease in carrying capacity may only stimulate density-dependent responses that quickly return population densities to pre-control levels. Consequently, habitat manipulation, either to reduce pest density or to divert the pest away from the commodity, has been pursued as an alternative. Habitat manipulation has proven effective in some circumstances and appears promising in others, but the approach is limited by our ability to identify limiting resources or highly preferred foods that can be manipulated economically and with the desired effect. Further, habitat manipulation is not always a long-term solution, may have unwanted effects on non-target species, and may be ineffective if not viewed on a regional scale. Nonetheless, the approach is promising in certain situations. Further research is needed.

Fifty-four landscaped areas in downtown Boston were surveyed for Norway rat (Rattus norvegicus) activity. Each location also was characterized based on size, types of plantings, density of plantings, type of mulch, and sanitary and maintenance conditions. Factors most associated with the presence of rats were dense contiguous stands of shrubbery (e.g., needled evergreens) and refuse/litter availability on the ground. Design criteria should include effective spacing of shrubbery, limiting mass plantings of dense shrubs, selection of plant varieties that grow with openness underneath, strategically-placed and rodent-proof refuse containers, and use of crushed-stone inspection strips. Rodent control should be considered when landscapes arc designed, and proper maintenance of landscaped areas should be part of urban rodent control programs.

Mountain beavers (Aplodontia rufa) cause considerable damage to forest trees in the Pacific Northwest. Feeding injuries result in mortality, growth losses. deformity of trees, and understocked plantations. Losses are most severe in new plantations with significant damage problems also occurring in sapling stands. Trapping, and placing physical barriers around individual trees, are the most common methods of control. Both methods are costly but effective in reducing damage.

Extensive, urban development of hillside areas in Los Angeles County has created an undesirable human interface with coyotes (Canis latrans). Plentiful, readily available household garbage, pet foods, and water have spawned abnormal numbers of bold coyotes that have adopted residential properties and the human environment as ideal habitat. Consequently, at least six persons have been attacked, including the death of a three-year old child, during the past three years. Selective use of padded steel traps, shooting, and public education are presently being used in problem areas by the Agricultural Commissioner in an attempt to reindoctrinate these predators into returning to their natural habits.

There are five species of meadow voles found in California. The two that are most economically important are Microtus californicus and Microtus montanus. Meadow vole populations are extremely cyclic, reaching a peak every four to six years. During these periods when the vole population is increasing in numbers, damage to crops like alfalfa, artichokes, potatoes, and sugar beets can occur. The best time to survey for vole activity is before the crop is planted. The grower or farm operator should look for vole activity in grassy borders around the crop or along roadsides and ditch bank areas. Snap-trapping may also be used to confirm the presence of voles. Clean cultivation and weed control on grassy borders adjacent to crops will help reduce potential harborage for voles. A small or localized vole population on a crop border is much easier to control than if the voles become established in the crop. Rodenticide-treated baits are very effective in reducing vole populations. Bait distribution may be done by spot-baiting, placing bait by hand, or by broadcasting, scattering bait over the entire infested area.

A program to control roof rats (Rattus rattus) has been conducted by the Orange County (CA) Vector Control District since 1975. Located in southern California just south of Los Angeles, urbanization takes up about ½ the total area of the county, and it is mainly a semi-desert situation with

During the summer months of 1979, public agencies in Ventura County, CA, received complaints which pointed to a rodent infestation of campground areas along the north coastal strip. Investigations revealed a widespread infestation of oceanfront riprap by roof rats (Rattus rattus). Visual surveillance, trapping, baiting and population-estimating techniques and results are described and discussed. Implementation of integrated pest management practices resulted in the reduction of rat populations to a no-complaint level and provided a framework for a long-term maintenance program.

Manipulation or alteration of habitat vegetation is used frequently with integrated pest management of certain vertebrate pest species. However, it has been less than satisfactory with ground squirrel species in many situations. Special plantings of tall grasses and broadleaf species were experimentally explored in an effort to make levee habitat less suitable for the California ground squirrel in the Sacramento Valley. The experimental plantings failed to achieve that objective for a variety of apparent or suspected reasons and, in fact, in some grass plots the number of ground squirrels increased over what was present prior to planting. Other problems associated with these experimental plantings, including aggressive tendencies of some species, are discussed.

The Formosan red-bellied tree squirrel (Callosciurus erythraeus) is a pest animal that causes serious damage to many conifer plantations in Taiwan. Poisoning has been the major means to control the damage. The feasibility of forestry control through habitat manipulation has been evaluated during the past 5 years. The objective of this study was to investigate the effects of forest-tending operations on the activity and damage by squirrels. Forest-tending conducted included weeding and thinning. Test sites were at three Japanese cedar (Cryptomeria japonica) plantations located in Chitou. The results of this study revealed that squirrel activity in the treated plots was greatly reduced. It was found that new damage done by the squirrels in treated areas was also reduced. This was particularly significant during an abnormal weather period when there was a continual rainstorm lasting for about 3 months. The treatments of weeding and thinning showed more significant effects on the reduction of squirrel activity than the reduction in the occurrence of new damages.

In addition to welcoming Conference participants, the author expresses his philosophy of the need for vertebrate pest control activities. Too few people understand that a highly stable animal-plant-soil equilibrium exists where man has not markedly altered the environment. In temperate regions, the balance of nature in natural habitats is little affected even when a large number of individuals of any one or several species of vertebrates are removed by man. The naturally evolved species that are present have acquired great resilience to offset various climatic and other catastrophes. In contrast, the type of habitat modification done by homeowners, farmers, and the like nearly always causes some vertebrates to become pests. Some conservationists, through protectionist zeal founded on ignorance of the population dynamics of vertebrates in altered environments, indirectly force many farmers to practice an undesirable form of biological control of vertebrate pests--clean farming. The farmers cannot afford to keep hedge rows and riparian vegetation because they will foster serious pest problems unless some other control is practiced. At this Conference the speakers will illustrate how they are seeking the most ecologically desirable protection of mankind's food, fiber, and other resources, including wildlife in general. All of the papers will shed light on the role that vertebrate pest control is playing in managing modified environments in perpetuity in a healthy manner.

Principal methods being used to alleviate browsing damage to Douglas-fir (Pseudotsuga menziesii) seedlings by black-tailed deer (Odocoileus hemionus columbianus) in the Pacific Northwest are animal repellents applied to foliage and plastic mesh cylinders around individual seedlings. As an alternate method, we demonstrated that prompt establishment of highly palatable native forbs reduced summer browsing on planted seedlings to the point that black-tailed deer were no longer a factor limiting Douglas-fir regeneration. We believe that establishing native forbs is a sound ecological approach to deer-reforestation problems; furthermore, it should have wide utility because it integrates forest- and wildlife-management objectives by promoting prompt regeneration of conifers and enhancing wildlife habitat.

Highly effective controls for the pine mouse (Pitymys pinetorum) were obtained for three years in apple orchards by means of herbaceous ground cover sprays of [(chloro 4 phenyl) 1 phenyl] acetyl 2 dioxo 1-3 indane at a rate of 0.2 lb. per acre of actual orchard. This toxicant from Europe is designated there as chlorophacinone. The spray residue persists for a maximum of about 30 days and was not found to be translocated to fruits nor was it detected in runoff water. Ingestion of the lethal agent is markedly enhanced by an adequate presence of forbs in the treated greenery. Too little attention has been directed to the basic differences in control between herbaceous type feeders and the seed consumers. CPN is now reported to give excellent results from large-scale applications by growers.

Methods for the control of problem opossums, bats, raccoons, and skunks are discussed. Basic biology of these animal species is provided. For the opossum, control methods include trapping, physical capture at night, or use of a strychnine formulation injected into eggs. The presence of bats in homes or other structures is a concern due to their potential infection with rabies. Bat biology and behavior is summarized, and bat-proofing of structures is recommended as a technique. Bats repellents for use in attics or other closed spaces are discussed. In some situations, professional fumigation of a structure to kill bats is needed, but it has several disadvantages and does not provide a permanent solution. Raccoon biology is summarized. When numerous, they can cause economic damage to gardens and crops and are especially destructive to corn fields. Raccoon trapping using a variety of traps and types of trap sets is described in detail. Exclusion of raccoons is possible by adding a single wire strand electrified by a fence charger to an existing fence. Where raccoons cause extensive damage to crops, they can be controlled using strychnine baits; formulas and instruction for strychnine-egg baits and strychnine-corn baits are provided. Skunk biology and behavior is summarized. Preventing their entry into structures is preferred over skunk destruction, as they have beneficial aspects by eating mice and insects. Techniques for excluding skunks are described in detail, including exclusionary methods to keep them out of poultry houses. Insecticides properly applied to lawns will reduce skunk damage to turf by eliminating insect and grub food sources. Methods to trap skunks are described, as are techniques and a formula for making strychnine-egg baits to kill skunks.

Muskrats, originally native to only two small areas of California, are now widespread in their distribution, where they can cause damage to some crops, but are of particular concern because of their burrowing in structures of irrigation canals and ditchbanks, waterways, and levees. Methods of canal and waterway construction can reduce or prevent damage, as can use of materials that exclude muskrat burrowing. Some materials have been shown to be repellent to muskrat burrowing when used to treat the soil near waterways. Reduction or elimination of weedy plant growth can be a deterrent in situations where no other food sources are nearby. Muskrat populations can be reduced or controlled by use of traps, burrow fumigants, shooting, or use of toxic bait; details of recommendations for use of these methods are included.

Damage to orchard crops and field crops in California by several species of native birds is described, covering biology, behavior, and typical damage caused by linnets (house finches), horned larks, crowned sparrows, and woodpeckers. The legal status of this birds is unique in California, as these migratory birds may be controlled under the authority of the California Department of Agriculture and their associated County Agricultural Commissioners. Bird exclusion, frightening, or other deterrent techniques should be tried first, and only when these are ineffective or impractical should lethal methods be used. Specific bait formulas and toxicants for bird control are under the authority of the state and are not provided here. Control of house finches in agricultural crops typically involved use of prebait followed by toxic bait exposed in orchards in bait troughs; trough design, placement, and use are discussed. For horned larks, lethal control is best accomplished by closely observing feeding behavior, and then exposing prebait followed by toxic bait in furrows, trails, or other similar depressions in the soil within crop fields. Frightening has also worked well, using carbide exploders, the “stake and flag” method, or “continuous string flagging,” especially when these scare tactics are installed in advance of or at the first sign of horned lark damage. Crowned sparrows prefer dense vegetation, so habitat management to remove such cover (including weedy borders along fields or fence rows) near crops or orchards can entirely prevent damage. In smaller plantings, wire frames to exclude crowned sparrows or dense flagging can prevent damage. Where lethal control is needed, prebait and then toxic bait is exposed in shallow v-shaped troughs 2 to 3 feet above ground level, alternately throughout the period of crop damage. Woodpecker damage can be a serious problem in walnut and almond orchards, or they can damage wooden structures. Selective shooting can be effective, as can application of chemical repellent materials on areas that are being damaged or adjacent ledges. Occasionally, woodpeckers have been successfully removed by use of Victor rat traps, or use of toxic baits in holes where woodpeckers store acorns.

Methods of controlling domestic pigeons, European starlings, and house sparrows are discussed in detail, with emphasis on urban bird problems. Trapping, exclusion, and roost dispersal by means of frightening devices (pyrotechnic tools such as cracker shells and fuse ropes, in particular) and roost sprays are described in detail. For capture of pigeons, both cage traps and cannon nets are described, with illustrations provided. Case studies are provided of successful dispersal of starling roosts by use of sprays formulated with aqueous ammonia and a wetting agent. Brief mention of use of avicides is included.

Recent research efforts to control blackbird damage to corn in South Dakota are described. The primary species responsible is the red-winged blackbird, but other associated species include yellow-headed and Brewers blackbirds, common grackles, and brown-headed cowbirds. The birds’ biology and behavior are described, as is damage assessment in corn fields. Bird banding efforts have revealed typical bird migration patterns and movement. Trapping with Miller-type cannon nets and with modified Australian crow traps have shown success. Other damage control techniques considered, investigated, and/or evaluated include bird-resistant variety of crops, habitat management, use of frightening devices, roost sprays with the organophosphate DRC-632, and baiting with the fright-producing chemical DRC-1327.

Northern Santa Clara County, California, has changed from an agricultural to an industrial-residential community in the past 10 to 15 years. Maturing shrubbery and fruit bearing trees in residential areas have provided ideal habitat for increased populations of roof rats. Advisory or educational control measures only met with partial response and little success in actually exterminating rats. It took an actual organized health department effort with diphacinone bait blocks to achieve adequate control in a given area of 400+ homes. An interesting legal complication is described as related to public rodent control on private property.