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In order to potentially reduce use of environmentally damaging rodenticides, integrated Pest Management (IPM) for rodents, or Ecologically Based Rodent Management (EBRM), proposes a more sustainable management approach using strategies informed by an increased understanding of rodent population and community ecology, including interactions with important predators, such as raptors. Nest boxes and perches can encourage raptor presence in agricultural areas and potentially enhance the regulatory ecosystem services provided by raptor predation of agricultural pests. To assess this idea, we studied American kestrels (widespread, generalist predators that readily use nest boxes) in a fruit-growing region of northwestern Michigan. The most common mammal prey in the diets of these kestrels from 2013 through 2016 were voles, which are considered the most important rodent pests in temperate fruit orchards. We utilized live trapping to measure small mammal abundances and activity during the summer at sites with and without active kestrel nest boxes; furthermore, we utilized camera trapping to measure small mammal presence during the winter, when damage to trees is most likely. As predicted, small mammal abundance and activity was lower at orchards with active kestrel boxes and at orchards that had been more recently mowed; however, these differences did not carry over as differences in winter presence in orchards. Our sampling demonstrated that voles were absent from orchards during both summer and winter, which suggests that orchards offer insufficient cover except under certain conditions, such as sustained snow cover. Instead, mice were the most abundant small mammals in most orchards during the summer and were also present during the winter. More evidence is therefore needed to determine the extent of orchard damage attributable to Peromyscus spp. and whether indirect effects of kestrels on Peromyscus spp. may reduce damage. We provide recommendations for future research on the effects of raptor predation in orchards.

Understanding distribution patterns and multitrophic interactions is critical for managing bat- and bird-mediated ecosystem services such as the suppression of pest and non-pest arthropods. Despite the ecological and economic importance of bats and birds in tropical forests, agroforestry systems, and agricultural systems mixed with natural forest, a systematic review of their impact is still missing. A growing number of bird and bat exclosure experiments has improved our knowledge allowing new conclusions regarding their roles in food webs and associated ecosystem services. Here, we review the distribution patterns of insectivorous birds and bats, their local and landscape drivers, and their effects on trophic cascades in tropical ecosystems. We report that for birds but not bats community composition and relative importance of functional groups changes conspicuously from forests to habitats including both agricultural areas and forests, here termed 'forest-agri' habitats, with reduced representation of insectivores in the latter. In contrast to previous theory regarding trophic cascade strength, we find that birds and bats reduce the density and biomass of arthropods in the tropics with effect sizes similar to those in temperate and boreal communities. The relative importance of birds versus bats in regulating pest abundances varies with season, geography and management. Birds and bats may even suppress tropical arthropod outbreaks, although positive effects on plant growth are not always reported. As both bats and birds are major agents of pest suppression, a better understanding of the local and landscape factors driving the variability of their impact is needed.

Understanding distribution patterns and multitrophic interactions is critical for managing bat- and bird-mediated ecosystem services such as the suppression of pest and non-pest arthropods. Despite the ecological and economic importance of bats and birds in tropical forests, agroforestry systems, and agricultural systems mixed with natural forest, a systematic review of their impact is still missing. A growing number of bird and bat exclosure experiments has improved our knowledge allowing new conclusions regarding their roles in food webs and associated ecosystem services. Here, we review the distribution patterns of insectivorous birds and bats, their local and landscape drivers, and their effects on trophic cascades in tropical ecosystems. We report that for birds but not bats community composition and relative importance of functional groups changes conspicuously from forests to habitats including both agricultural areas and forests, here termed 'forest-agri' habitats, with reduced representation of insectivores in the latter. In contrast to previous theory regarding trophic cascade strength, we find that birds and bats reduce the density and biomass of arthropods in the tropics with effect sizes similar to those in temperate and boreal communities. The relative importance of birds versus bats in regulating pest abundances varies with season, geography and management. Birds and bats may even suppress tropical arthropod outbreaks, although positive effects on plant growth are not always reported. As both bats and birds are major agents of pest suppression, a better understanding of the local and landscape factors driving the variability of their impact is needed.

Economic impacts, risk factors, and deterrent strategies related to fruit damage by birds were investigated in a four year study across North America. Here we focus primarily on bird management strategies tested in the Pacific Northwest, including visual deterrents such as hawk-kites, inflatable tube-men, and falconry. Fields protected by professional bird-abatement falconry showed less blueberry damage than non-falconry fields. Neither hawk kites nor kite-falconry combinations showed strong damage prevention. A pilot trial of inflatable tube-men in blueberries showed a potential deterrent effect in one of three blocks. Bird management strategies that are biodiversity-friendly, such as falconry and predator nest boxes, may also be useful in marketing fruit.

Fruit producers have identified bird damage as a critical issue that has received limited attention from researchers. A USDA study estimated that birds cost producers in seven states tens of millions of dollars through fruit loss and management efforts. Despite these costs, research has been uncoordinated and piecemeal, leaving producers with few, well-tested management options. We describe several objectives to strive for in order to achieve the goal of providing producers with region-specific, cost-effective, and environmentally sustainable bird management strategies. These objectives include 1) quantifying economic consequences of bird damage for producers, consumers, and regional economies, and determining costs and benefits of various management techniques; 2) identifying amounts of damage attributable to specific bird species across crops and regions; 3) determining how bird damage varies within and across spatial scales (orchard, landscape, region); 4) evaluating consumer responses to management strategies and potential effects on marketing; 5) integrating economic, biological, and consumer information, i.e. using a systems approach, to determine the management strategies that should be tested; and 6) testing management strategies for efficacy with replicated, well-controlled experimental designs. By focusing on these objectives and coordinating activities among researchers and extension personnel from different regions of the country and from different disciplines, we will maximize efficiency in addressing this issue on a national scale while providing individual producers with region-specific information to guide their bird management efforts. Communication among researchers, extension personnel, and producers will be critical to minimize the costs of bird damage.