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Sexual success of males in lek breeding systems is often determined by display activities that require high energetic costs and may represent honest signals of male quality to females. In this context, manakins (Aves, Pipridae) evolved behavioral, morphological, and physiological adaptations that enable complex display maneuvers, and a high rate of fruit ingestion is needed to cope with the energetic costs of lekking activities. We examined the relationship between different displays (rolled-snaps, flights-down, and snap-jumps) and fruit consumption (a proxy for energy intake) by White-bearded Manakin males (Manacus manacus). We conducted a fruit supplementation experiment and recorded male displays in 23 arenas on 5 leks in southeastern Brazil. The flight-down was the display most related to fruit consumption (and energy refueling) by males of the While-bearded Manakin. This display seems to be decisive to the mating success of Manacus males; once inside a lek area, females are driven to display arenas by flights-down of males as an obligatory stage before copulation. This study opens a promising avenue for further field experiments designed to test how local food resources differentially impact display behavior among males in leks. Received 24 May 2017. Accepted 10 October 2017.Key words: frugivory, leks, male display, Manacus, sexual selection.O succsso sexual de machos no sistema reprodutivo de lek e frequentemente determinado por exibicoes que rcquerem um alto custo energetico e que podem representar sinais honestos de qualidade para as femeas. Neste contexto, os tangaras (Aves, Pipridae) evoluiram adaptacoes comportamentais, morfologicas e fisiologicas que permitem complexas manobras de exibicoes, e uma alta taxa de ingestao de frutos e necessaria para atingir os custos energeticos em suas atividades. Nos avaliamos a relacao entre diferentes atividades de exibicao (rolled-snaps, flights down e jump-snaps) e o consumo de frutos (e suposta energia ganha) de rendeiras machos (Manacus manacus). Nos conduzimos um experimento com oferecimento de frutos em arenas de exibicoes de 23 machos em cinco areas de lek no sudeste do Brasil. Flight-down e a manobra de exibicao mais plausivel relacionada ao consumo de frutos (e reabastecimento energetico) por machos de M. manacus. A importancia desta atividade de exibicao parece ser decisiva para o sucesso reprodutivo de machos: uma vez dentro da area de lek, as femeas sao direcionadas para arenas de exibicao com os voos direcionados (flights-down) de machos como uma etapa obrigatoria antes do acasalamento. Este estudo abre um campo promissor de experimentos desenhados para testar como recursos alimentares locais influcneiam diretamente exibicoes de machos em areas de lek.Palavras chavc: exibicao de machos, frugivoria, leks. Manacus. selecao sexual., In lekking species, elaborate courtship displays by males are common. Males are usually clumped spatially and compete among themselves to copulate with females, who actively choose mates (Hoglund and Alatalo [...]

Bird populations vary both spatially and temporally with consequences for patterns of species richness and community composition. Many species of birds have declined in abundance over the last 14 years at a site in lowland Ecuador. Here, we examine impacts of those declines on composition of bird assemblages on two 100-ha plots in lowland forest at Tiputini Biodiversity Station, eastern Ecuador. Birds were sampled with mist nets (2001-2014) and by direct observations (2003-2006, 2009, 2010, 2013, and 2014). Species accumulation curves were similar on both plots but varied among years; rates of accumulation were particularly low in 2013, following declines in abundance of many species. Community composition differed between the two study plots based on species and guild composition; annual changes at the community level reflected changes in abundance of many species, particularly insectivores. Overall, assemblages of birds at this site in lowland Ecuador showed substantial variation over time and. to a lesser degree, between plots. If bird populations eventually return to levels seen in the early years of this study, we might expect community composition to resemble that of earlier years as well. Results demonstrate the value of long-term (>10 years) studies on replicate plots to help understand dynamics of bird communities in lowland tropical forests. Received 29 June 2015. Accepted 10 December 2015. Key words: community composition, guild, long-term, lowland forest, species richness, tropical., Bird populations vary in abundance over time (Blake et al. 1994, Ballard et al. 2003, Jones et al. 2007, Stouffer et al. 2011, Shaw et al. 2013, Blake and Loiselle [...]

Glyphorynchus spirurus (Wedge-billed Woodcreeper) is one of the most common birds in the understory of many tropical forests of Central and South America but few studies have focused on its abundance and distribution. We use data from mist nets and direct observations over a 10-year period to examine patterns of abundance and distribution on two 100-ha plots (Harpia, Puma), ~1.7 km apart in lowland forest of eastern Ecuador. Birds were captured in mist nets (96 nets/plot) that were open for ~6 hrs/day for 1 day each in January and February; direct observations were made along transects within each plot during February (7 yrs) and April (4 yrs). We recorded 861 captures (447 recaptures) on Harpia and 963 captures (540 recaptures) on Puma; capture rates (birds/100 mist-net hrs) were slightly higher on Puma, largely a result of the greater numbers of recaptures. Number of individuals captured per year did not differ between plots. Mean (± SE) recapture distance within a year was less on Harpia (94.5 ± 6.1 m) than on Puma (121.6 ± 7.3 m) but recapture distances between years did not differ between plots (108 and 97 m, respectively for Harpia and Puma). Number of captures had a clumped distribution with some nets capturing many more individuals than others; number of captures per net was not correlated with captures at nearby nets. We recorded 490 Glyphorynchus during observations on Harpia (Feb samples) and 384 on Puma. Number of observations was greater on Harpia during 6 of 7 years. Numbers of observations had clumped distribution patterns on both plots; significant autocorrelations likely reflected the difficulty of detecting individuals by voice when >50 m from a transect. Comparisons with published data from other sites in Central and South America indicate considerable spatial variation in abundance but reasons for geographic variation in abundance need further investigation. Received 5 February 2012. Accepted 6 May 2012., The Wedge-billed Woodcreeper (Glyphorynchus spirurus; Glyphorynchus hereafter) is the smallest of the woodcreepers (Furnariidae). It is widely distributed from southern Mexico to western Ecuador, northern Bolivia, and Amazonia to eastern [...]

We investigated species composition of the bat assemblage in continuous forest and natural forest islands in a savanna ecosystem in northern Bolivia. We captured 396 bats of 24 species. Five species accounted for almost 70% of the captures: Sturnira lilium, Artibeus obscurus, Carollia brevicauda, Carollia perspicillata, and Artibeus lituratus. Species composition of the bat assemblage differed between continuous forest and forest islands; Artibeus jamaicensis and S. lilium were captured more often in islands, whereas Platyrrhinus helleri and Mesophylla macconnelli were more common in the continuous forest. The distribution of species over the forest islands and the continuous forest revealed a nested distribution pattern, with the continuous forest having the highest number of species, and the smallest island having the fewest species. However, bats were almost 5-fold more abundant in forest islands than in continuous forest. Examination of recapture data indicated movements of bats among forest islands and between islands and continuous forest. Our results suggest that bat populations, especially in the fruit-eating guild, can persist in a naturally fragmented landscape. Key words: bats, Chiroptera, distribution, fragmentation, tropical savanna

Environmental correlates and geographic spacing of leks were compared for six species of manakins (Pipridae) on two 100-ha study plots in eastern Ecuador. The 'hotspot' hypothesis of lek evolution suggests that males should aggregate where females are most likely to be encountered. For ecologically similar species that co-occur at a site, leks are predicted to be clustered in space and, thus, to overlap in macroscale environmental characteristics. The geographic spacing and environmental characteristics of lek sites we observed were inconsistent with the hotspot hypothesis for lek evolution. In general, little geographic overlap occurred among leks, and geographic spacing of leks among heterospecifics more closely fit a regular than a clumped pattern. Further, environmental conditions of leks varied among species with respect to elevation and topography. Leks of some species were more likely to occur on hilltops or ridge tops (e.g., Machaeropterus regulus, Pipra erythrocephala), whereas others appeared to prefer highly dissected drainages (e.g., P. pipra), relatively flat terrain near streams (e.g., Chiroxiphia pareola), or seasonally inundated forests (e.g., P. filicauda). Using randomly placed leks, we found evidence that certain lek environments may be limited, which is consistent with observed levels of population abundances on the two plots. Such environmental limits may constrain lek placement and size. Further study is needed to determine the reproductive implications of placing leks in apparently suboptimal environments, though such compromises may reflect males making the best of a bad situation. Key words: behavior and ecology, habitat selection, lek mating system, manakins, tropical wet forest. RESUMEN.--Se compararon los correlatos ambientales y el espaciamiento geografico para seis especies de saltarines (Pipridae) en dos parcelas de estudio de 100 ha en el oriente de Ecuador. La hipotesis de los 'sitios calientes' para explicar la evolucion de las asambleas de cortejo ('leks') sugiere que los machos deberian agregarse en lugares en donde es mas pobable encontrar a las hembras. Para especies ecologicamente similares que coexisten en un lugar, se predice que las asambleas deberian estar agregadas en el espacio, por lo que deberian superponerse en cuanto a sus caracteristicas ambientales a una escala macro. El espaciamiento geografico y las caracteristicas ambientales de los sitios donde se ubicaron las asambleas que observamos fueron inconsistentes con lo esperado de acuerdo a la hipotesis de los puntos calientes. En general, existio poca superposicion geografica entre las asambleas, y el espaciamiento geografico de asambleas heteroespecificas se ajusto mas a un patron regular que a uno agregado. Ademas, las condiciones ambientales de los sitios de ubicacion de las asambleas variaron entre especies con respecto a la elevacion y la topografia. Las asambleas de algunas especies se encontraron mas en las cimas de colinas o en los filos (e.g., Machaeropterus regulus, Pipra erythrocephala), mientras que otras parecieron preferir cuencas fuertemente disectadas (e.g., P. pipra), terrenos relativamente planos cerca de quebradas (e.g., Chiroxiphia pareola) o bosques estacionalmente inundados (e.g., P. jilicauda). Utilizando asambleas ubicadas aleatoriamente, encontramos evidencia de que ciertos ambientes usados por las asambleas podrian estar limitados, lo que concuerda con los niveles de abundancia poblacional observados en las dos parcelas. Estas limitaciones ambientales podrian restringir la ubicacion y el tamano de las asambleas. Es necesario realizar mas estudios para determinar las implicaciones reproductivas de ubicar las asambleas en ambientes aparentemente suboptimos, aunque dichos compromisos podrian reflejar que los machos sacan el mejor provecho posible de situaciones desfavorables.

Over the past decade, the field of molecular genetics has revolutionized our understanding of avian mating systems, by demonstrating that social bonds might not accurately reflect parentage because of unknown levels of cryptic mating (e.g., extra-pair copulations). Use of molecular genetics tools for paternity analysis requires genetic material from putative parents and nestlings. Unfortunately, high nest predation rates often preclude detailed genetic studies of tropical taxa. Here, we describe a nondestructive method that increases the efficiency of obtaining genetic material from offspring for a group of tropical passerines (Pipridae). The method entails replacing eggs with plaster replicas, incubating eggs artificially, and returning hatchlings to their original nests for further development. This method greatly improved our ability to sample offspring, as we collected genetic material from 100% of manipulated nests, compared to 52% of unmanipulated nests. Key words: ex situ incubation, manakin, nest predation, Pipridae, plaster eggs. Durante la ultima decada, el campo de la genetica molecular ha revolucionado el entendimiento de los sistemas de apareamiento de las aves, demostrando que los lazos sociales observados pueden no reflejar paternidad con precision, debido a niveles desconocidos de apareamiento criptico (e.g., copulaciones extra-pareja). El uso de herramientas de genetica molecular para el analisis de paternidad requiere material genetico de padres putativos y polluelos. Desafortunadamente, la alta tasa de depredacion de nidos en especies tropicales usualmente impide la realizacion de estudios geneticos detallados. Aqui se describe un metodo no destructivo que incrementa la eficacia para obtener material genetico de polluelos de un grupo de aves paseriformes tropicales (Pipridae). El metodo consiste en reemplazar huevos con replicas de yeso, incubar los huevos artificialmente y devolver los polluelos a los nidos originales para su posterior desarrollo. Este metodo incremental significativamente nuestra habilidad de muestrear polluelos, pudiendo colectar material genetico del 100% de los nidos manipulados, comparado con una colecta de material genetico de solo el 52% de los nidos no manipulados.

Lekking is classified as a form of male-dominance polygyny in which males lack control of resources essential for the acquisition of females. Of particular interest to behavioral ecologists has been the mechanistic basis of male spatial aggregation and the maintenance of site fidelity over time. The 'hotspot' hypothesis has been proposed as both an ultimate and proximate mechanism by which males aggregate in locations where females are likely to be encountered. The hypothesis has been extended to include areas of the environment that act to constrain females' use of space. Here, we test a prediction of this hypothesis for three species of manakins (Pipridae): that leks are located in places where fruit, the main food for these frugivorous birds, is plentiful. We compared four lek sites with four non-lek control sites of Golden-headed (Pipra erythrocephala), Wire-tailed (P. filicauda), and White-crowned (P. pipra) manakins in an Amazonian forest in Ecuador. Our results show that lek sites had higher fruit biomass than control sites. Moreover, lek sites had more plants bearing ripe fruit as well as a higher fruit biomass per plant than control sites. Thus, our results support the environmental hotspot hypothesis as an explanation for current lek site occupancy and suggest that fruit availability may also explain the placement of traditional manakin lekking sites. We also discuss a potential direct benefit for subordinate male manakins derived from the notion of central-place foraging and public information-sharing. Received 7 June 2004, accepted 2 July 2005. Key words: hotspot hypothesis, lek placement, male aggregation, manakins, Pipridae. Resumen.--El apareamiento en asambleas de cortejo esta clasificado como un tipo de poliginia basada en la dominancia de los machos, en la que estos carecen de control sobre recursos esenciales para la adquisicion de hembras. Los mecanismos que subyacen a la agregacion espacial de los machos y al mantenimiento de la fidelidad a los sitios han sido de particular interes para los ecologos del comportamiento. La hipotesis de los 'puntos calientes' (lugares en los que se concentran recursos) ha sido propuesta como un mecanismo tanto filtimo como proximo para explicar por que los machos se agregan en lugares donde es altamente probable que se encuentren hembras. Esta hipotesis ha sido extendida para incluir a las areas del ambiente que actuan limitando el uso del espacio por parte de las hembras. En este estudio ponemos a prueba una prediccion de esta hipotesis para tres especies de saltarines (Pipridae): las asambleas de cortejo deben estar ubicadas en lugares donde los frutos, la principal fuente de alimento de estas aves frugivoras, son abundantes. Comparamos cuatro sitios con asambleas de cortejo con cuatro sitios control sin estas para Pipra erythrocephala, P. filicauda y P. pipra en un bosque amazonico en Ecuador. Nuestros resultados indicaron que los lugares en que estaban ubicadas las asambleas de cortejo presentaron una mayor biomasa de frutos que los sitios control. Ademas, los sitios de cortejo presentaron mas plantas con frutos maduros y una mayor biomasa de frutos por planta que los sitios control. Pot lo tanto, nuestros resultados apoyan la hipotesis de los 'puntos calientes' de concentracion de recursos como una explicacion para la ocupacion actual de los sitios por las asambleas de cortejo, y sugieren que la disponibilidad de frutos podria igualmente explicar las ubicaciones tradicionales de estas asambleas en los saltarines. Tambien discutimos un beneficio directo potencial para los machos subordinados derivado de los conceptos de forrajeo alrededor de un lugar central y de compartir informacion publica.

We used capture and recapture data (1985 to 1994) to examine seasonal variation in habitat use, movements within and among habitats, and survival rates of manakins (Manacus candei, Corapipo altera, Pipra mentalis, P. pipra) in northeastern Costa Rica. Manakins were captured in young and old second-growth woodlands in the lowlands and in old-growth forest at approximately 50, 500, and 1,000 m. Manakin species differed in their use of habitats, with old-growth forest species showing large and predictable seasonal variation in capture rates. Corapipo capture rates in lowland (nonbreeding) habitats were greater during the wet season than during the dry season and were greater in old-growth forest than in second growth. Capture rates at 500 m were higher in the dry season. Pipra mentalis capture rates were high in second growth and old growth. Capture rates were higher in the wet season and were correlated with capture rates of Corapipo, indicating that at least some individual P. mentalis migrate along the elevational gradient. P. pipra capture rates were highest at 1,000 m; few individuals descended to lowlands in the wet season. Manacus capture rates were highest in young second growth and did not vary between wet and dry seasons. Use of second-growth habitats by species typically associated with old-growth forests illustrates the value of maintaining a mosaic of habitats to accommodate seasonal changes in use of habitats. Contrary to expectations based on lek mating systems, there was little evidence that movements within habitats (i.e. recapture distances) varied between sexes. Yet, recapture percentages were higher in all species for adult females than males. Adult survival rates were ~0.75 for Manacus in young second growth, 0.62 for Corapipo in old-growth forest at 50 m and 0.66 at 500 m, and 0.70 for Pipra mentalis in lowland old-growth forest. Results support the suggestion that geographic variation in survival rates may be common in the tropics and illustrate the need for examining survival rates separately by age and sex. Received 29 June 2000, accepted 8 October 2001.

Species diversity and community composition of birds change rapidly along elevational gradients in Costa Rica. Such changes are of interest ecologically and illustrate the value of protecting continuous gradients of forest. We used mist nets and point counts to sample birds along an elevational gradient on the northeastern Caribbean slope of the Cordillera Central in Costa Rica. Sites included mature tropical wet forest (50 m); tropical wet, cool transition forest (500 m); tropical premontane rain forest (1,000 m); and tropical lower montane rain forest (1,500 and 2,000 m). We recorded 261 species from 40 families, including 168 species captured in mist nets (7,312 captures) and 226 detected during point counts (17,071 observations). The sample included 40 threatened species, 56 elevational migrants, and 22 latitudinal migrants. Species richness (based on rarefaction analyses) changed little from 50 to 1,000 m but was lower at 1,500 and 2,000 m. Mist nets and point counts often provided similar views of community structure among sites based on relative importance of difference categories of species (e.g. migrant status, trophic status). Nonetheless, important differences existed in numbers and types of species represented by the two methods. Ninety-three species were detected on point counts only and 35 were captured only. Ten families, including ecologically important ones such as Psittacidae and Cotingidae, were not represented by captures. Elevational migrants and threatened species occurred throughout the gradient, illustrating the need to protect forest at all elevations. A comparable study from the Cordillera de Tilaran (Young et al. 1998) demonstrated similar patterns of species change along an elevational gradient. Comparisons with that study illustrated that point counts are a valuable complement to mist-net studies. Both studies indicated the diverse nature of the avifauna along elevational gradients in Costa Rica.

Birds directly affect seed dispersal through (1) the number of seeds they remove and (2) where and in what condition those seeds are deposited. Dispersal effectiveness is a composite of these quality and quantity components of seed dispersal. In this study, number of seeds removed and patterns of seed deposition by six bird species were determined for four shrubs in the Melastomataceae. Bird species differed in both quantity and quality components of seed dispersal. Bird species that contributed most to the quantity component of seed dispersal were not always the same as those that contributed most to the quality component. Thus, to evaluate the ecological roles of frugivores and their effectiveness as seed dispersers requires integration across various processes involved in seed dispersal (removal, deposition, etc.). In contrast to canopy trees, shrubs apparently have a relatively small set of seed dispersers, which makes them more vulnerable to the extinction of a seed disperser. Key words: birds, impact on plants; diets of understory frugivores; frugivory; habitat selection; La Selva, Costa Rica; Melastomataceae; seed dispersal by birds; tropical wet forest., INTRODUCTION Animals disperse the seeds of most plant species in Neotropical wet forests, especially in the understory where about 98% of treelet and shrub species have fleshy fruits (e.g., Gentry [...]

A study of the influence of successional variation in vegetation on bird species living in young second-growth woodlands in Costa Rica revealed significant changes in vegetation structure and composition, with increase in trees and woody shrubs and a decline in herbaceous shrubs. The appearance of forest-habit birds in second-growth woodland and the complete disappearance of birds dependent on successional habitats occurred. Adaptive diet changes in fruit-eating birds suggested rapid change in plant and bird populations in second-growth woodlands.

Models of gap-phase regeneration in tropical wet forests are based primarily on studies of canopy trees. These paradigms are derived from studies of a small number of species whose life history traits place them easily into 'pioneer' or 'climax' species. Woody plants of the forest understory, subcanopy trees and shrubs, are known to affect significantly regeneration dynamics in treefall gaps, yet we lack fundamental information on life history characteristics of understory plants that could permit their incorporation into gap regeneration models. We investigated intra- and interspecific variability in early life history characteristics of understory Melastomataceae species of different growth forms and adult distributions from the lowland tropical rain forest at La Selva Biological Station, Costa Rica. We examined germination patterns in vitro (22 species), effects on germination of passage through birds (5 species), seedling establishment in the field (3 species), and growth in different light environments (8 species). Established seedlings were significantly more abundant in gaps than in nearby understory sites. This pattern was generally applicable to all melastomes studied, regardless of the habitat where adults were normally most abundant. Seedlings were more common in the root pits and on the root mounds of uprooted trees, even though there was less light available to the seedlings in these microsites than elsewhere in the gaps. In a series of germination trials in vitro, most seeds germinated readily within 1-2 wk. Comparisons of germination rates between seeds collected from bird droppings and seeds extracted from fruits by hand gave varied results. With one exception, seeds of shade-tolerant species germinated more slowly following passage through birds, while seeds from high-light-demanding species germinated more rapidly after passing through birds. Seeds of three common species were sown directly into different microsites within gaps and understory control sites. In contrast to the germination trials, emergence percentages in the field ranged from 4% in understory sites to 21% in gap centers. Survival after 1 yr was low (0.1%-0.4%). After 1 yr, these seedlings were small (

Bird communities in tropical forest are tremendously diverse relative to those in temperate forests; more species have been reported from Costa Rica than from all of North America (Stiles et [...]

We studied temporal fluctuations in fruit production by plants and in populations of understory fruit-eating birds at three elevations (50, 500, and 1000 m) in Costa Rican wet forests over a 12-16 mo period to investigate effects of resource variation on bird movements and community structure. We used mist nets to monitor changes in frugivore abundance, migration patterns, and breeding and molting cycles. We sampled understory fruits of each forest concurrent with studies of frugivores. Both frugivores and fruit exhibited considerable seasonal variation in abundance. Peak frugivore capture rates occurred during peak periods of ripe fruit abundance. Altitudinal migrants left lower montane (1000 m) forest during periods of fruit scarcity and were present in lowland (50 m) and foothill (500 m) forest when ripe fruit was abundant. Migrants, both altitudinal and temperate, accumulated fat before migration, and perhaps (for altitudinal migrants) in anticipation of breeding. Some residents also put on fat before breeding. Breeding was seasonal at all forests and occurred when ripe fruit abundance was low. Results of this study indicate that birds may track changes in resource abundance. Thus, variation in resource abundance influences dynamics of bird communities, both in terms of species composition and abundance. Further, results illustrate the importance of viewing communities from different scales; dynamics at a local scale (e.g., one elevation) can be influenced by changes in conditions (e.g., fruit abundance) elsewhere. That some species regularly move along elevational gradients implies that preservation of many species and of the biotic integrity of entire systems may require conservation of large, n connected blocks of suitable habitat.

The article evaluates five different nature conservation models, applied to 11 Brazilian forest bird species. Models were found to differ significantly in reserve network flexibility and scope, indicating caution should be used to prevent overestimation of species occurrences.

Second growth has replaced lowland forest in many parts of the Neotropics, providing valuable habitat for many resident and migrant bird species. Given the prevalence of such habitats and the potential benefit for conservation of biodiversity, it is important to understand patterns of diversity in second growth and old growth. Descriptions of species-distribution patterns may depend, however, on method(s) used to sample birds. We used data from mist nets and point counts to (1) describe species diversity and community composition in second-growth (young and old) and old-growth forests at La Selva Biological Station, Costa Rica; and (2) to evaluate perspectives on community composition provided by the two methods. We recorded 249 species from 39 families, including 196 species captured in mist nets (10,019 captures) and 215 recorded during point counts (15,577 observations), which represents ~78% of the terrestrial avifauna known from La Selva (excluding accidentals and birds characteristic of aquatic or aerial habitats). There were 32 threatened species, 22 elevational migrants, and 40 latitudinal migrants. Species richness (based on rarefaction analyses of capture and count data) was greatest in the youngest site. Latitudinal migrants were particularly common in second growth; elevational migrants were present in both young and old forest, but were more important in old-growth forest. Several threatened species common in second growth were not found in old-growth forests. Trophic composition varied less among sites than did species composition. Mist nets and point counts differed in numbers and types of species detected. Counts detected more species than nets in old-growth forest, but not in young second growth. Mist nets detected 62% of the terrestrial avifauna, and point counts detected 68%. Fifty-three species were observed but not captured, and 34 species were captured but not observed. Six families were not represented by mist-net captures. Data from mist nets and point counts both support the conclusion that second-growth vegetation provides habitat for many species. Received 28 January 2000, accepted 16 September 2000.

Jorge Servin (1,4) Susan Lyndaker Lindsey (2) Bette A. Loiselle (3) ABSTRACT.--An observation of opportunistic scavenging by a female Pileated Woodpecker (Dryocopus pileatus) in Missouri is reported. The bird visited [...]

Ornithological journals are perceived as prestigious and of good quality depending on their names. Bird-named journals such as Auk, Condor, Emu and Forktail are usually ranked lower compared to such periodicals as Journal of Avian Biology and Journal of Field Ornithology, mainly because their names are misleading as to their content. American Ornithologists' Union members should reevaluate the packaging of the Auk, to ensure that it continues its tradition as an outstanding international journal and to promote contemporary ornithology.

These two books are the newest additions to a growing number of conservation biology textbooks. The late 1980's and early 1990's have seen the emergence of conservation biology programs on [...]