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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.

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.

Landscape enhancements such as nest boxes can attract birds to agricultural areas, where they can provide ecosystem services such as pest reduction through their consumption of crop pests. However, there are large gaps in knowledge about how birds respond to enhancements. From 2014 to 2018 we installed American Kestrel (Falco sparverius; hereafter kestrel) nest boxes in a blueberry production region in western Michigan. From 2015 to 2018 we conducted surveys to monitor kestrel presence along 1.6-km transect segments (hereafter, sites) to estimate kestrel occupancy in areas with and without boxes. We also monitored box occupancy and reproductive success. Kestrel presence increased over time in the study area although there was some uncertainty in this trend. The presence of a box at a site did not increase kestrel presence there, but boxes in neighboring sites did increase presence. This indicated that enriching an area with boxes increases kestrel presence. Box occupancy rates were positively influenced by occupancy of the same box the previous year. Percent successful nests ranged from 75 to 100 percent, and mean number of fledglings produced was approximately 4 per nest box. Our results showed that nest boxes can serve as effective landscape enhancements to attract kestrels to agricultural landscapes, but the degree to which kestrels occupy boxes can vary geographically. Local-scale studies can provide information about the potential benefits and challenges of using nest boxes as a pest management tool. Las mejoras del paisaje, tales como la colocación de cajas nido, pueden atraer aves a las áreas agrícolas, donde pueden prestar servicios ecosistémicos como la reducción de plagas en cultivos. Sin embargo, existen grandes lagunas en el conocimiento sobre cómo responden las aves a estas mejoras. De 2014 a 2018 instalamos cajas nido para Falco sparverius en una región de producción de arándanos en el oeste de Michigan. De 2015 a 2018 realizamos censos para determinar la presencia de la especie a lo largo de transectos de 1.6 km (en adelante, sitios) y estimar la ocupación de F. sparverius en áreas con y sin cajas nido. También monitoreamos la ocupación de las cajas nido y el éxito reproductivo. La presencia de F. sparverius aumentó con el tiempo en el área de estudio, aunque hubo cierta incertidumbre en esta tendencia. La presencia de una caja nido en un sitio no aumentó la presencia de la especie allí, pero las cajas en lugares vecinos sí aumentaron la presencia. Esto indicó que enriquecer un área con cajas nido aumenta la presencia de F. sparverius. Las tasas de ocupación de cajas nido se vieron influidas positivamente por la ocupación de la misma caja el año anterior. El porcentaje de nidos exitosos varió del 75 al 100 por ciento, y el número medio de volantones producidos fue de aproximadamente 4 por caja nido. Nuestros resultados mostraron que las cajas nido pueden servir como mejoras efectivas del paisaje para atraer a F. sparverius a los paisajes agrícolas, pero el grado en que los individuos ocupan las cajas puede variar geográficamente. Los estudios a escala local pueden proporcionar información sobre los posibles beneficios y desafíos del uso de cajas nido como herramienta para el control de plagas. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

Pest birds cause substantial and costly damage to crops. Managing birds is complex because (1) they are highly mobile, (2) they habituate quickly to many deterrents, (3) some species provide benefits to farmers by deterring and consuming pest insects, rodents, and other birds, and (4) birds are highly valued by many people. Thus, farmers have many issues to consider when developing bird management strategies. Here I discuss recent work indicating that farmer adoption of sustainable agricultural practices is more likely when practices are effective, clear guidelines for implementation are available, implementation is relatively easy, and when practices are linked, in farmers' minds and logistically, with other farm management practices. This manuscript draws together information about these factors for common bird management tactics to ad in the development of sustainable bird management strategies by farmers and the development of education programs for farmers by extension personnel and researchers. Such strategies will necessarily involve combinations of tactics, following the framework of Integrated Pest Management. [ABSTRACT FROM AUTHOR]