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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.

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.

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]

Many studies investigating edge effects on forest-nesting birds have focused on nest success. Fewer have examined edge effects on other components of fitness. Nestling growth rates have been positively correlated with food availability, which may differ at edges compared to the forest interior. However, previous work has not examined growth as a function of distance to edge and edge type. We investigated whether edge type, distance to edge, hatching date, brood size, brood parasitism, year, and site influenced growth rates of wings, tarsi, and mass of nestling Wood Thrushes (Hylocichla mustelina) using regression tree analyses. Simultaneously, we examined edge effects on daily nest survival. We conducted our study in southwestern Michigan in 2002 and 2003. We located 175 nests and measured nestlings from 61 nests. Contrary to expectations, tarsal and mass growth rates were more rapid near edges than in the forest interior and tarsal growth rates were more rapid near gradual edge types than near abrupt edge types. Wing chord growth rates were more rapid in the forest interior than at edges. Mass and tarsal growth rates were more rapid later in the breeding season, when brood sizes were smaller. We found no effect of edge type or distance to edge on nest survival. The influence of edge on nestling growth rate but not nest survival suggests nestling growth rates may indicate edge-interior and edge type differences in habitat quality, even when high regional fragmentation levels overwhelm potential edge-interior differences in nest survival. Key words: distance to edge, edge effects, edge type, Hylocichla mustelina, nest survival, nestling growth rates, Wood Thrush. Muchos de los estudios que investigan los efectos de borde en las aves que nidifican en bosques se han enfocado en el exito de los nidos. Menos estudios han examinado los efectos de borde en otros componentes de la adecuacion biologica. Las tasas de crecimiento de los pichones han sido positivamente correlacionadas con la disponibilidad de alimentos, la cual puede diferir entre los bordes y el interior del bosque. Sin embargo, los trabajos previos no han examinado el crecimiento en funcion de la distancia al borde y del tipo de borde. Usando analisis de arboles de regresion, investigamos si el tipo de borde, la distancia al borde, la fecha de eclosion, el tamano de la nidada, el parasitismo de la nidada, el ano y el sitio influenciaron las tasas de crecimiento de las alas, el tarso y el peso de los pichones de Hylocichla mustelina. Simultaneamente, examinamos los efectos de borde en la supervivencia diaria de los nidos. Realizamos nuestro estudio en el sudoeste de Michigan en 2002 y 2003. Localizamos 175 nidos y medimos pichones provenientes de 61 nidos. Contrariamente a lo que esperabamos, las tasas de incremento del tarso y del peso fueron mayores cerca de los bordes que en el interior del bosque, y las tasas de incremento del tarso fueron mayores cerca de bordes de tipo gradual que cerca de bordes de tipo abrupto. Las tasas de incremento de la cuerda alar fueron mayores en el interior del bosque que en los bordes. Las tasas de incremento del peso y el tarso fueron mayores al final de la estacion reproductiva, cuando el tamano de la nidada fue mas pequeno. No encontramos un efecto del tipo de borde y de la distancia al borde en la supervivencia de los nidos. La influencia del borde en la tasa de crecimiento de los pichones, pero no en la supervivencia de los nidos, sugiere que la tasa de crecimiento de los pichones podria indicar diferencias en la calidad de habitat entre borde e interior y entre tipos de borde, aun cuando los altos niveles de fragmentacion regionales tengan efectos superiores a las diferencias potenciales en la supervivencia del nido entre borde e interior.

We used radiotelemetry to study behavior of White-throated Robins (Turdus assimilis) during the postfledging dependent period. The study was conducted in a mixed agricultural and forested landscape in southern Costa Rica from March through August of 2001 and 2002. A transmitter was attached to one fledgling per brood (n = 53). Each bird was located daily prior to dispersal. We compared survivorship, habitat use, and movements of fledglings from (1) nests in coffee plantations and (2) nests in cattle pastures. The probability of surviving the first three weeks out of the nest was 0.67 [+ or -] 0.07 (SE) for fledglings from nests in all habitats, 0.58 [+ or -] 0.10 for fledglings from nests in coffee, and 0.74 [+ or -] 0.26 for fledglings from nests in pasture. Fledglings from nests in pasture left their nesting habitat at younger ages than did those from nests in coffee, and most birds from both habitats moved into forest when they left their nesting habitat. Pasture was rarely used during the postfledging period, whereas coffee plantations were used extensively. Fledglings that remained in agricultural habitats (coffee or pasture) were less likely to survive until dispersal than were those that moved into forested areas. Average daily distances from the nest gradually increased until fledglings dispersed away from the natal area, always into forest, and were not different for birds from pasture or coffee. White-throated Robins can nest successfully in agricultural habitats, but use of forest positively influenced survivorship of young during the postfledging dependent period.

We document characteristics of the previously undescribed nest, nest site, and eggs of the Ochre-breasted Antpitta (Grallaricula flavirostris). We found three nests in 1999 and 2000 in the Talamanca Mountains of southern Costa Rica. The nests were cup shaped and constructed primarily of green moss with linings of thin sticks and black rhizomorphs. Mean nest height above the ground was 3.1 m. Nests were located in the forks of slim saplings in two eases and, in one case, in a larger tree at a point where several smaller branches left the trunk. We observed clutches of one and two eggs. Eggs appeared pale reddish brown with some darker spotting. The incubation period was 17-21 d and we estimate the nestling period lasts 14-16 d., Many aspects of the biology of most antpittas (Formicariidae) are not well understood because the birds are easily overlooked and relatively difficult to observe (Robbins et al. 1994), with new [...]