Rain Forest Structure at Forest-Pasture Edges in Northeastern Costa Rica

Land-use change in the Sarapiquí region of Costa Rica has resulted in a fragmented forest landscape with abrupt edges between forest and pasture. Forest responses to edge effects vary widely and can significantly affect ecosystem integrity. Our objective was to examine forest structure at 20+ yr old forest-pasture edges in Sarapiquí. Three transects with 0.095-ha plots at seven distances from forest edges were established in each of six forest patches. Stem density, basal area, and aboveground biomass in trees and palms ≥ 10-cm diameter at breast height were measured in all plots. In addition, hemispherical photographs were taken to determine leaf area index, understory light availability, and percent canopy openness. Linear mixed-effects models showed significantly higher tree stem density at forest edges, relative to interiors, a pattern reflected by increased stem density, basal area, and aboveground biomass in small diameter trees (≤ 20 cm) growing near edges. No differences in total tree basal area, aboveground biomass, or hemispherical photograph-derived parameters were detected across the forest edge to interior gradient. The recruitment of small diameter trees following edge creation has contributed to the development of dense vegetation at the forest edge and has aided in the maintenance of similar tree basal area and aboveground biomass between edge and interior environments. These data reflect on the robustness of forest edges in Sarapiquí, a characteristic that will likely minimize future detrimental edge effects and promote a number of high-value environmental services in these forests.     

Forest Restoration Treatment Effects on the Nesting Success of Western Bluebirds (Sialia mexicana)

We examined the effects of presettlement forest restoration treatments on the nesting success of Western Bluebirds in ponderosa pine forests of northwestern Arizona, U.S.A. From 1998 to 2001 we monitored 97 active Western Bluebird nests, 41 in current‐condition untreated forest and 56 in restoration‐treated forest. We found no effect of restoration treatments on clutch size and little effect on the number of nestlings per nest. However, in treated forest stands number of fledglings per nest averaged 1.6 times greater, and probability of a nest surviving to successfully fledge at least one young was up to 4.2 times greater than in untreated forest. Probability of a nest succeeding averaged 0.39 ± 0.11 (SE) and 0.75 ± 0.06 from 1999 to 2001 in untreated and treated forests, respectively. In addition, in treated forest, average number of nests infested with the blowfly parasite Protocalliphora sialia was up to 4.3 times greater, and number of parasites per fledgling was up to 10.7 times greater than in untreated forest. Overall, the data suggest that in treated forest Western Bluebirds have a higher probability of successfully fledging young, but they are at greater risk of parasitic infestations, of which the ultimate effects on post‐fledging survival are unknown.     

Landscape-Scale Environmental and Floristic Variation in Costa Rican Old-Growth Rain Forest Remnants

Studies of tropical rain forest beta-diversity debate environmental determinism versus dispersal limitation as principal mechanisms underlying floristic variation. We examined the relationship between soil characteristics, terrain, climate variation, and rain forest composition across a 3000 km² area in northeastern Costa Rica. Canopy tree and arboreal palm species abundance and soils were measured from 127 0.25-ha plots across Caribbean lowlands and foothills. Plot elevation, slope, temperature, and precipitation variation were taken from digital grids. Ordination of forest data yielded three floristic groups with strong affinities to foothills and differing lowland environments. Variation in floristics, soil texture, and climate conditions showed parallel patterns of significantly positive spatial autocorrelation up to 13 km and significantly negative correlation beyond 40 km. Partial Mantel tests resulted in a significant correlation between floristic distance and terrain, climate and soil textural variables controlling the effect of geographical distance. Separate comparisons for palm species showed significant correlation with Mg and Ca concentrations among other soil factors. Arboreal palm species demonstrated a stronger relationship with soil factors than did canopy trees. Correlation between floristic data and geographical distance, related to seed dispersal or unmeasured variables, was not significant after controlling for soil characteristics and elevation. Canopy trees and palms showed differing relationships to soil and other environmental factors, but lend greater support for a niche-assembly hypothesis than to a major role for dispersal limitation in determining species turnover for this landscape.     

Down by the riverside: Riparian edge effects on three monkey species in a fragmented Costa Rican forest

Rivers represent natural edges in forests, serving as transition zones between landscapes. Natural edge effects are important to study to understand how intrinsic habitat variations affect wildlife as well as the impact of human-induced forest fragmentation. We examined the influence of riparian and anthropogenic edge on mantled howler, white-faced capuchin, Central American spider monkeys, and vegetation structure at La Suerte Biological Research Station (abbreviated as LSBRS), Costa Rica. We predicted lower monkey encounter rate, tree species richness, and median dbh at both edge types compared to interior and that monkeys would show species-specific responses to edge based on size and diet. We expected large, folivorous–frugivorous howler monkeys and small, generalist capuchins would be found at increased density in forest edge, while large, frugivorous spider monkeys would be found at decreased density in forest edge. We conducted population and vegetation surveys along interior, riparian, and anthropogenic edge transects at LSBRS and used GLMM to compare vegetation and monkey encounter rate. Tree species richness and median dbh were higher in forest interior than anthropogenic edge zones. Although spider monkey encounter rate did not vary between forest edges and interior, howler monkeys were encountered at highest density in riparian edge, while capuchins were encountered at highest density in anthropogenic edge. Our results indicate that diverse forest edges have varying effects on biota. Vegetation was negatively affected by forest edges, while monkey species showed species-specific edge preferences. Our findings suggest that riparian zones should be prioritized for conservation in Neotropical forests.     

Influence of Edge Exposure on Tree Seedling Species Recruitment in Tropical Rain Forest Fragments1

Edge creation has a pronounced influence on the understory vegetation, but the effects of edges on seedling species recruitment are still poorly understood. In Central Amazonia, 9–19 years after fragmentation, we recorded species richness and net seedling recruitment rate in 1 ha blocks exposed to none, one, or multiple edges within forest fragments. One‐hectare blocks were located in the center (no edge), the edge (one edge), the corners (two edges) of 10 and 100 ha fragments, and in a 1 ha fragment (four edges). In 1991, we counted all tree seedlings 5–100 cm tall found within permanent 1 m² plots located within the 1 ha blocks. In May 1993, we manually removed all seedlings that were smaller than 1 m tall from the permanent plots. Six years and five months later (October 1999), all new seedlings recruited into the plots were counted and classified into distinct morphospecies. Species richness of recruited seedlings, scaled by total seedling density, declined from the center to the edge, the corner blocks, and then to the 1 ha fragment. Overall, the four‐edged, 1 ha fragment had the poorest species richness and the non‐edged 100 ha central block the highest. The total number of recruited individuals was 40 percent less than that previously present, with the 100 ha corner having the lowest recruitment. Pairwise comparisons showed that species similarity was related to edge number for the 100 and 1 ha fragments. Species rank/abundance curves showed that a subset of species was common in all blocks within the fragments, and that the 100 ha center held more rare species than any other 1 ha block. This study demonstrated that, in a given fragment patch, the number of tree seedling species recruited varied inversely with the number of edges.     

Positive roadside edge effects on artificial nest survival in a lowland Atlantic Forest

Road construction is considered to be one of the primary causes of forest fragmentation, and little is known about how roads affect bird reproductive success. The objective of this study was to assess the survival rate of artificial nests along an edge associated with a highway and in the interior of a tabuleiro forest. The study was performed at the Sooretama Biological Reserve, on the margins of federal highway BR‐101, between September and October 2015. A total of 168 artificial nests with a Common quail (Coturnix coturnix) egg in each nest were placed along six sampling transects, at distances of 2, 25, 50, 100, 200, 400, and 800 m from the highway toward the forest interior. We used logistic regression and estimated daily survival rate (DSR) using the “Nest Survival” function in the program MARK to estimate artificial nest survival and assessed the effect of the distance from the highway. The artificial nest survival rate was significantly higher on the highway margins than at other distances. The results show that artificial nests located up to 25 m from the highway have a greater success probability (over 95%) and a significant decrease in success probability more than 50 m from the highway. Although we cannot rule out other nonroad‐specific edge effects on artificial nest predation, our results suggest that the impacts of the highway (e.g., noise, vibration, visual stimuli) cause predators to avoid the road's surroundings (up to 25 m into the forest) when selecting their feeding sites, which partially supports the predation release hypothesis.     

Changes in Habitat Use at Rain Forest Edges Through Succession: a Case Study of Understory Birds in the Brazilian Amazon

Primary tropical rain forests are being rapidly perforated with new edges via roads, logging, and pastures, and vast areas of secondary forest accumulate following abandonment of agricultural lands. To determine how insectivorous Amazonian understory birds respond to edges between primary rain forest and three age classes of secondary forest, we radio‐tracked two woodcreepers (Glyphorynchus spirurus, N = 17; Xiphorhynchus pardalotus, N = 18) and a terrestrial antthrush (Formicarius colma, N = 19). We modeled species‐specific response to distance to forest edge (a continuous variable) based on observations at varying distances from the primary‐secondary forest interface. All species avoided 8–14‐yr‐old secondary forest. Glyphorynchus spirurus and F. colma mostly remained within primary forest <100 m from the young edge. Young F. colma rarely penetrated >100 m into secondary forest 27–31 yr old. Young Formicarius colma and most G. spirurus showed a unimodal response to 8–14‐yr‐old secondary forest, with relative activity concentrated just inside primary forest. After land abandonment, G. spirurus was the first to recover to the point where there was no detectable edge response (after 11–14 yr), whereas X. pardalotus was intermediate (15–20 yr), and F. colma last (28–30 yr +). Given the relatively quick recovery by our woodcreeper species, new legislation on protection of secondary forests > 20‐yr old in Brazil's Pará state may represent a new opportunity for conservation and management; however, secondary forest must mature to at least 30 yr before the full compliment of rain forest‐dependent species can use secondary forest without adverse edge effects.     

Pollinators of Syntopic Marcgravia Species in Costa Rican Lowland Rain Forest: Bats and Opossums

Abstract: The visitors of four syntopically occurring species of Marcgravia (M. nervosa, M. serrae, M. mexicana , and M. nepen-thoides ) in the Atlantic lowland rain forest at La Selva Biological Station in Costa Rica were observed. The four species differed in flowering phenology and morphology of inflorescences. Flowers of all species opened during the night and the stamens dropped before dawn. All species were visited by small nectar-feeding bats (Phyllostomidae: Glossophaginae). Marcgrovia nepen-thoides , with much larger nectaries, additionally attracted two species of opossums, Caluromys derbianus and Didelphis marsu-pious . Judging from the large distance between nectaries and flowers, glossophagine bats probably are inefficient pollinators of this species, and merely exploit a non-flying mammal pollination system.     

Nest survival in year‐round breeding tropical red‐capped larks Calandrella cinerea increases with higher nest abundance but decreases with higher invertebrate availability and rainfall

Nest survival is critical to breeding in birds and plays an important role in life‐history evolution and population dynamics. Studies evaluating the proximate factors involved in explaining nest survival and the resulting temporal patterns are biased in favor of temperate regions. Yet, such studies are especially pertinent to the tropics, where nest predation rates are typically high and environmental conditions often allow for year‐round breeding. To tease apart the effects of calendar month and year, population‐level breeding activity and environmental conditions, we studied nest survival over a 64‐month period in equatorial, year‐round breeding red‐capped larks Calandrella cinerea in Kenya. We show that daily nest survival rates varied with time, but not in a predictable seasonal fashion among months or consistently among years. We found negative influences of flying invertebrate biomass and rain on nest survival and higher survival of nests when nests were more abundant, which suggests that nest predation resulted from incidental predation. Although an increase in nest predation is often attributed to an increase in nest predators, we suggest that in our study, it may be caused by altered predator activity resulting from increased activity of the primary prey, invertebrates, rather than activity of the red‐capped larks. Our results emphasize the need to conduct more studies in Afro‐tropical regions because proximate mechanisms explaining nest predation can be different in the unpredictable and highly variable environments of the tropics compared with the relatively predictable seasonal changes found in temperate regions. Such studies will aid in better understanding of the environmental influences on life‐history variation and population dynamics in birds.     

Phenology and Stem Diameter Increment Seasonality in a Costa Rican Wet Tropical Forest

The relationship between phenology and tree stem diameter increment is largely unexplored in tropical species, especially in wet tropical forests. To explore links between these phenomena, we measured stem diameter increment and phenology of ten canopy tree species from a range of functional types in the Atlantic lowlands of Costa Rica to test for seasonal and interannual patterns. We measured stem diameter increment using band dendrometers and visually assessed leaf and reproductive phenology monthly from 1997 to 2000. We categorized the species into groups based on patterns of leaf exchange and reproduction. Species were either deciduous with synchronous or asynchronous leaf drop, or evergreen with continuous or seasonal leaf flushing. Flowering occurred supra-annually, annually, or continuously. Of the ten species studied, four species, Cecropia insignis, Dipteryx panamensis, Lecythis ampla, and Simarouba amara , had consistent seasonal stem diameter increment patterns in both years. Dipteryx panamensis and L. ampla were deciduous with synchronized leaf drop . Cecropia insignis was evergreen and produced new leaves continuously. Simarouba amara , also evergreen, exchanged leaves over a brief period once a year. We tested whether stem diameter increment was correlated to phenology using logistic regression. Leaflessness significantly explained patterns in stem diameter increment but reproductive phenology did not. Deciduous trees were 2.6–9.3 times more likely to grow less than average the month following leaffall than in months when trees had full crowns.     

High density of white-faced capuchins (Cebus capucinus) and habitat quality in the Taboga Forest of Costa Rica

Across the globe, primates are threatened by human activities. This is especially true for species found in tropical dry forests, which remain largely unprotected. Our ability to predict primate abundance in the face of human activity depends on different species' sensitivities as well as on the characteristics of the forest itself. We studied plant and primate distribution and abundance in the Taboga Forest, a 516-ha tropical dry forest surrounded by agricultural fields in northwestern Costa Rica. We found that the density of white-faced capuchins (Cebus capucinus) at Taboga is 2–6 times higher than reported for other long-term white-faced capuchin sites. Using plant transects, we also found relatively high species richness, diversity, and equitability compared with other tropical dry forests. Edge transects (i.e., within 100 m from the forest boundary) differed from interior transects in two ways: (a) tree species associated with dry forest succession were well-established in the edge and (b) canopy cover in the edge was maintained year-round, while the interior forest was deciduous. Sighting rates for capuchins were higher near water sources but did not vary between the edge and interior forest. For comparison, we also found the same to be true for the only other primate in the Taboga Forest, mantled howler monkeys (Alouatta palliata). Year-round access to water might explain why some primate species can flourish even alongside anthropogenic disturbance. Forest fragments like Taboga may support high densities of some species because they provide a mosaic of habitats and key resources that buffer adverse ecological conditions.     

广东常见森林鸟类的繁殖习性记述

2016和2017年,在广东鼎湖山国家级自然保护区及广东同乐大山省级自然保护区,用行为观察法和微型摄像机记录了淡眉雀鹛（Alcippehueti）、红嘴相思鸟（Leiothrixlutea）、栗颈凤鹛（Staphida torqueola）和褐顶雀鹛（Schoeniparus brunneus）等12种鸟类的繁殖习性。描述了它们的巢特征、卵重、卵大小、窝卵数及育雏等繁殖参数。研究发现：1）与历史数据相比,经过近30年的时间,在广东鼎湖山的淡眉雀鹛筑巢高度增加;2）与国内其他地区相比,红嘴相思鸟的筑巢高度也增加;3）发现乌鹃（Surniculus lugubris）和棕腹鹰鹃（Hierococcyx nisicolor）将淡眉雀鹛巢中的淡眉雀鹛雏鸟移出巢外;4）发现淡眉雀鹛亲鸟将其巢中的鸟卵和雏鸟移出巢外。     

Edge Effects of Linear Canopy Openings on Tropical Rain Forest Understory Microclimate

We investigated microclimatic edge gradients associated with grassy powerlines, paved highways and perennial creeks in wet tropical forest in northeastern Australia during wet and dry seasons. Photosynthetically active radiation, air temperature and vapor pressure deficit, soil temperature, canopy temperature, soil moisture, and air speed in the rain forest understory were measured during traverses perpendicular to the forest edge. Light intensity was elevated near the edges of powerlines, highways, and creeks, but this effect was strongest for creek edges. Air temperature and vapor pressure deficit were elevated near powerline edges in the dry season and highway edges in both wet and dry seasons but were not elevated near creek edges in either season. In contrast, soil moisture was lowered near creek edges but not near either powerline or highway edges. No edge gradients were detected for air speed. Canopy temperature was elevated near highway edges and lowered near powerline edges in the wet season but no edge gradients in canopy temperature were detected near creek edges in either the wet or the dry season. We suggest that these different edge gradients may be largely the result of differences in the fluxes of latent and sensible heat within each type of linear canopy opening, with periodic flood disturbance assisting by maintaining a more open canopy near creek edges. Our data indicate that the nature of the linear canopy opening is at least as important as the width in determining the nature and severity of microclimatic edge effects, analogous to the "matrix effect" of traditional fragmentation studies.     

Forest Succession and Distance from Forest Edge in an Afro‐Tropical Grassland1

Forest succession on degraded tropical lands often is slowed by impoverished seed banks and low rates of seed dispersal. Within degraded landscapes, remnant forests are potential seed sources that could enhance nearby forest succession. The spatial extent that forest can influence succession, however, remains largely unstudied. In abandoned agricultural lands in Kibale National Park, Uganda, recurrent fires have helped perpetuate the dominance of tall (2–3 m) grasses. We examined the effects of distance from forest and grassland vegetation structure on succession in a grassland having several years of fire exclusion. At 10 and 25 m from forest edge, we quantified vegetation patterns, seed predation, and survival of planted tree seedlings. Natural vegetation was similar at both distances, as was seed (eight species) and seedling (six species) survival; however, distance may be important at spatial or temporal scales not examined in this study. Our results offer insight into forest succession on degraded tropical grasslands following fire exclusion. Naturally recruited trees and tree seedlings were scarce, and seed survival was low (20% after 7 mo). While seedling survival was high (95% after 6 to 8 mo), seedling shoot growth was very slow (x?= 0.5 cm/100 d), suggesting that survivorship eventually may decline. Recurrent fires often impede forest succession in degraded tropical grasslands; however, even with fire exclusion, our study suggests that forest succession can be very slow, even in close proximity to forest.     

Seed Dispersal by Birds and Bats in Lowland Philippine Forest Successional Area

In the tropical forests of SE Asia, only a few studies have dealt with the role animal dispersal plays in early forest succession and rehabilitation, and a comparison of bird and bat dispersal is even rarer. We investigated seed dispersal by birds and bats in a successional area in the lowland dipterocarp forest of the Subic Watershed Forest Reserve (SWFR) in Luzon Island, Philippines. Using pairs of day and night traps, we collected seeds during 3 mo of wet season and 3 mo of dry season in a 1.2-ha study site. Bird-dispersed seeds predominated over those dispersed by bats in terms of both seed abundance and number of seed species. The most abundant endozoochorous seed species were significantly biased toward either bird or bat dispersal. Birds and bats appeared to compete more strongly for fruit resources during the dry season than during the wet season, and bats responded more to changes in the seasons than birds did. GLM analyses showed that the factor that had the strongest influence on overall seed distribution was the number of fleshy-fruited trees surrounding the traps, and that the distribution pattern of day-dispersed seeds was affected by more physical factors (number of trees, size of trees, presence of fleshy-fruited and conspecific trees) in the study site than the pattern of night-dispersed seeds were. Given that birds are the more important dispersers in the study site, restoration efforts in SWFR might benefit by focusing on attracting these dispersers into its degraded habitats.     

Variation in Seedling Density and Seed Predation Indicators for the Emergent Tree Dipteryx panamensis in Continuous and Fragmented Rain Forest1

Seedling density and the condition of stony endocarps of the tree Dipteryx panamensis were assessed in protected continuous forest and two forest fragments exposed to hunting and selective logging. Seedling density was higher in forest fragments than in continuous forest, while more whole endocarps and fewer chewed and half endocarps were found in fragments, indicating lower seed predation at fragment sites. These findings appear to contradict two earlier D. panamensis studies and we discuss methodological differences that could account for our disparate results. Hunting and fragmentation effects on mammal populations are suggested as a cause for the altered recruitment pattern in fragments.     

Arthropod Assemblages in Epiphyte Mats of Costa Rican Cloud Forests

Tropical cloud forests are functionally important ecosystems, but are severely threatened due to deforestation and fragmentation. Epiphyte mats, accumulations of live vegetation and dead organic matter on tree trunks and branches, are a conspicuous component of cloud forests and harbor diverse assemblages of meso- and microarthropods. We compared the morphospecies richness, composition, and abundance of arthropods in epiphyte mats between primary and secondary forests of Monteverde, Costa Rica, and at two nearby replicate sites. Epiphyte mats were thinner and less structurally diverse in secondary forest. We collected ca 36,000 micro- and mesoarthropods from epiphyte mats in the 2-yr study. Whereas arthropod morphospecies richness did not differ among forest types, arthropod abundance was significantly higher in secondary forest due to larger numbers of ants, especially Solenopsis spp. Arthropod assemblages showed a high degree of taxonomic overlap both within and between primary and secondary forests (Jaccard abundance-based similarity = 0.93–0.96). Although characteristics of the arthropod fauna proved to be similar among sites and between forest types, there was a significant temporal effect: arthropod morphospecies richness in epiphyte mats generally was lower in the dry season (February–May), when many taxa probably became dormant or sought shelter against desiccation in deeper portions of mats.     

Consequences of Fragmentation of Tropical Moist Forest for Birds and Their Role in Predation of Herbivorous Insects

The consequences of habitat alteration on the role of understory insectivorous birds as predators of herbivorous insects in tropical forests are poorly understood. To examine whether fragmentation may affect the top–down controls of herbivory, we compared the number of species, individuals, and the community structure of insectivorous birds between fragments and continuous tropical moist forest in Mexico. We also registered insect herbivore abundances and conducted a larvae predation experiment to evaluate the potential role of insectivorous birds as predators of herbivorous insects. We recorded 63 bird species from 22 families, 43 percent of which were insectivorous birds. Species richness, abundance, and diversity of the avian community were higher in continuous forest compared with forest fragments. For insectivorous birds in particular, there was low similarity in avian insectivore communities between forest types, and forest fragments had more heavily dominated communities of avian insectivores. During the dry season, forest fragments presented significantly higher predation rates on artificial caterpillars, and lower abundance of herbivorous Lepidoptera larvae, compared with continuous forest. Furthermore, there was a significant negative correlation between artificial caterpillar predation rate and larval Lepidoptera abundance, with higher rates of predation in sample sites of low Lepidoptera abundance. Hence, the potentially greater light in the dry season combined with a more dominated avian insectivore community in forest fragments may facilitate increased predation by avian insectivores, resulting in a decline in abundance of larval Lepidoptera, with implications for the process of insect‐driven herbivory in forest fragments.     

Estimates of Apparent Survival Rates for Forest Birds in Eastern Ecuador

Knowledge of survival rates of Neotropical landbirds remains limited, with estimates of apparent survival available from relatively few sites and species. We used capture–mark–recapture models to estimate apparent survival of 31 species from eastern Ecuador based on data collected from 2001 to 2006. Models assuming constant survival had highest support for 27 species; models incorporating effects of transients were highest for four. Average apparent survival across 30 species of passerines was 0.58 (± 0.02 SE); apparent survival was lower during the first interval after initial capture (φ₁: mean = 0.49 ± 0.03) than during subsequent intervals (φ₂: mean = 0.60 ± 0.02). Apparent survival was similar among three families represented by at least four species (Thamnophilidae: 0.57 ± 0.03, N = 10; Furnariidae: 0.59 ± 0.03, N = 5; Pipridae: 0.56 ± 0.02, N = 4). There was no indication that species that occur in flocks had higher survival than nonflocking species (obligate flock members: 0.57 ± 0.03, N = 10; facultative flock members: 0.56 ± 0.04, N = 5; nonflocking: 0.59 ± 0.03, N = 15). Comparisons of published estimates of apparent survival of tropical species demonstrated substantial differences among species and, in some cases, within species across different sites in the Neotropics. Our results support previous studies that concluded that early estimates of high (> 85%) survival in tropical birds may not be representative of all tropical species. Future studies should focus on understanding factors ( e.g. , life-history traits) that promote differences in survival among species within tropical forests.     

Short‐Term Responses of Birds to Forest Gaps and Understory: An Assessment of Reduced‐Impact Logging in a Lowland Amazon Forest1

We studied physiognomy‐specific (i.e., gaps vs. understory) responses of birds to low harvest (18.7 m³/ha), reduced‐impact logging by comparing 3500 mist net captures in control and cut blocks of an Amazonian terra firme forest in Brazil at 20–42 mo postharvest. Species richness did not differ significantly between control (92 species) and cut (85) forest based on rarefaction to 1200 captures. Fifty‐six percent of all species were shared between control and cut forest, compared to the 64 percent shared between control blocks. Higher captures of nectarivores and frugivores in cut forest likely occurred as a consequence of postharvest resource blooms. Higher captures of some insectivores in cut as compared to control forest were unexpected, attributable to increased wandering or shifts from association with midstory to understory as a consequence of habitat alteration. Logging influenced capture rates for 21 species, either consistently, or via positive interaction with physiognomy or time (13 species higher in cut forest and 8 species higher in control forest). Cut understory sites had lower diversity (H′) and scaled dominance than understory and gap sites in control forest. Temporal changes in captures may have resulted from successional dynamics in cut forest: two guilds and three species increased in abundance. Increases in abundances of guilds and particular species were more prevalent in control than in cut forest, suggesting that logging displaced birds to control forest. In general, the effects of logging were relatively minor; low harvest rates and reduced‐impact methods may help to retain aspects of avian biodiversity in Amazon forest understories.