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Most studies of cooperatively breeding species have revealed that indirect fitness gains from helping are lower than benefits gained from direct reproduction. Exceptions to this 'best of a bad job' strategy are rare. Brown Jays (Cyanocorax morio) in Monteverde, Costa Rica, live in large groups (mean = 10 individuals) and have never been observed to breed as unaided pairs. Helpers provide a substantial percentage (70%) of all nestling feedings. Together, these observations suggest that helping may be crucial for reproductive success in this population. We used multivariate models to examine the effect of helpers on offspring production using a long-term data set. Data on nest-site success and brood reduction suggested that predation was the major cause of nesting failure. Nesting in an isolated tree was the major determinant of successful nestling production, and our data indicate that small groups (less than 9 individuals) may not be able to acquire or defend territories that contain suitable nesting sites. The number of juveniles (young surviving 30 days after leaving the nest) and yearlings was positively related to group size, even after removing groups that nested only in non-isolated trees. Small groups were also more likely than large groups to have total reproductive failure in a season. Helpers may increase juvenile survival by reducing predation, increasing juvenile condition, or providing learning opportunities for foraging and antipredator behaviors. Helpers on their natal territories receive some indirect benefits, though these are low compared with independent breeding. Immigrant male helpers may benefit primarily by gaining future breeding opportunities. Delayed benefits related to territory inheritance and dispersal coalitions may be the best explanation for helping in this population. Key words: Brown Jay, cooperative breeding, Cyanocorax morio, helpers, New World jays, reproductive success. La mayoria de los estudios sobre especies que presentan cria cooperativa hart revelado que las ganancias indirectas sobre la adecuacion por la presencia de ayudantes son menores que los beneficios ganados por la reproduccion directa. Las excepciones a esta estrategia de 'lo mejor de un mal trabajo' son raras. En Monteverde, Costa Rica, los individuos de Cyanocorax morio viven en grupos de gran tamano (media = 10 individuos) y nunca han sido observados reproduciendose en parejas sin ayudantes. Los ayudantes proporcionan un porcentaje substancial (70%) del total de la alimentacion de los polluelos en el nido. En conjunto, estas observaciones sugieren que la ayuda puede ser crucial para el exito reproductivo en esta poblacion. Usamos modelos multivariados para examinar el efecto de los ayudantes sobre la produccion de progenie utilizando una base de datos de largo plazo. Los datos sobre el exito de sitios de nidificacion y reduccion de la nidada sugieren que la depredaci6n es la principal causa de fracaso en la nidificacion. La nidificacion en un arbol aislado fue la principal determinante de una produccion exitosa de polluelos, y nuestros datos indican que los grupos pequenos (de menos de 9 individuos) pueden no ser capaces de adquirir o defender territorios que contengan sitios de nidificacion adecuados. El numero de juveniles (polluelos que sobreviven mas de 30 dias luego de abandonar el nido) y de individuos de un ano de edad se relacionaron positivamente con el tamano del grupo, incluso despues de eliminar del analisis a los grupos que anidaron solo en arboles no aislados. Ademas, los grupos pequenos tuvieron una mayor probabilidad de tener un fracaso total de nidificacion en una estacion reproductiva que los grupos de mayor tamano. Los ayudantes pueden aumentar la supervivencia de los juveniles al reducir la depredacion, aumentar la condicion de los juveniles o al proveer oportunidades de aprendizaje de comportamientos de forrajeo o de comportamientos para evitar la depredacion. Aunque los individuos que se quedan como ayudantes en sus territorios natales reciben algunos beneficios indirectos, estos son bajos en comparacion con los de la reproduccion directa. Los ayudantes machos inmigrantes pueden beneficiarse principalmente al obtener oportunidades reproductivas futuras. Los beneficios futuros relacionados con la herencia de territorios y con coaliciones de dispersion podrian ser las mejores explicaciones para la presencia de ayudantes en esta poblacion.

I used playbacks of recorded group song to survey and capture Black-breasted Wood-Quail (Odontophorus leucolaemus), a cloud forest endemic, in Monteverde, Costa Rica. This species is abundant in the dense understory of large windbreaks, forest fragments, and continuous forest of the Monteverde Reserve Complex. Mean covey size was four adults (range = 2-9 adults) and mean density, which did not differ between fragmented and continuous forest, was one covey per 3.3 ha. Wood-Quail defended all-purpose group territories and coveys persisted from one year to the next, indicating a group structure that is very different from what is found in most New World quail. A peak in breeding activity occurred at the transition from the wet to the dry season and larger groups produced significantly more juveniles than smaller groups in this population. Playbacks were a useful technique for detecting Black-breasted Wood-Quail; coveys responded to 65% of survey attempts by chorus and approach. By repeating the survey just three times, I was able to detect 91% [+ or -] 5% of all coveys that were known from extensive searches to occur in the remnant forest patches of the Monteverde community. The year-round sociality that is seen in this species is due in part to the retention of young on the natal territory beyond the age of sexual maturity. The intriguing relationship between group size and reproductive success in this population suggests the wood-quail may provide the first demonstration of a cooperative breeding system in the Galliformes. Key words: Galliformes, Odontophoridae, Odontophorus leucolaemus, playbacks, social birds, territory. Resumen. Utilice grabaciones de coros y duos para realizar censos y capturar individuos de Odontophorus leucolaemus, una especie endamica del bosque nublado en Monteverde, Costa Rica. Esta especie es abundante en zonas densas de sotobosque, en grandes areas de rompe-vientos, en fragmentos de bosque y en el bosque continuo de la red de reservas de Monteverde. El tamano de grupo promedio fue de cuatro adultos (variando entre 2 y 9 adultos) y la densidad promedio, que no vario entre el bosque fragmentado y el continuo, rue de un grupo pot cada 3.3 hectareas. Los grupos sociales de O. leucolaemus defendieron los territorios de usos multiples y estas asociaciones persistieron de un ano al proximo, indicando una estructura grupal que es muy diferente de la observada en la mayoria de las codornices del nuevo mundo. Hubo una temporada de alta reproduccion durante la transicion entre la estacion seca y la estacion de lluvias. En esta poblacion, los grupos grandes produjeron mas juveniles que los grupos pequenos. El uso de grabaciones fue una tecnica eficaz para realizar los censos; los individuos de O. leucolaemus respondieron con coros y acercamientos en el 65% de los muestreos. Al repetir los muestreos solamente tres veces, pude localizar el 91% [+ or -] 5% de los grupos que fueron registrados durante busquedas prolongadas en los fragmentos de bosque en la comunidad de Monteverde. En O. leucolaemus, la dinamica de grupo persiste durante todo el ano debido, en parte, a la retencion de las crias en los territorios natales luego de alcanzar la madurez sexual. La correlacion inesperada entre el tamano de los grupos y su exito reproductivo sugiere que las codornices podrian ser el primer ejemplo de un sistema de reproduccion cooperativa en los Galliformes.

Decades of fruitful research on the study of vocal communication in birds have provided surprisingly little evidence of a predation cost associated with singing. In this paper, 1 report the first observational evidence of a risk of predation associated with chorusing in a Neotropical wood-quail. Black breasted Wood-Quail (Odontophorus leucolaemus) live in groups year-round and produce coordinated group choruses or duets. Three mammalian and two avian species of predators were attracted to playbacks of recorded wood-quail choruses that 1 used during population surveys and capture attempts from March to August, 2000-2002. The trade-off between signaling and predation risk may be an important force in the evolution of chorusing in New World quails. Received 12 February 2004, accepted 19 July 2004., Long distance vocalizations are used for territory defense, mate attraction, and other functions in a variety of animals (Bradbury and Vehrencamp 1998, Todt and Naguib 2000). Whenever such signals are [...]

Defense of group-held resources is a common and widely accepted function of territorial interactions between neighboring groups. In addition, territorial interactions could provide opportunities to assess members of neighboring groups and reproductive opportunities there, or to solidify status in the home group. We studied group-level characteristics and individual participation in territorial encounters in the cooperatively breeding Brown Jay (Cyanocorax morio). Intergroup encounters at stable territory boundaries include both aggressive and affiliative behavior, which suggests that a territorial encounter could function as both a resource defense mechanism and as an arena for social interactions. Territory characteristics that increase the probability of contact between groups (long boundaries, large combined group size, and home range overlap) explain much of the variation in frequency of territorial encounters. Male-biased dispersal was more common to neighboring groups with long boundaries, supporting the idea that frequent interactions between neighbors facilitate dispersal. Females usually inherit breeding positions on their natal territories, and participation in intergroup encounters by females does not vary with age or breeding status. In addition to defending group resources, females on their natal territories could be defending their positions in the breeding queue. Immigrant females are not likely to breed successfully, or to disperse again, and they participated less than expected. Participation by both natal and immigrant males varied by age; young males, at the ages when dispersal and intergroup forays are most likely, participated more than expected, whereas older males ([greater than or equal to] 4 years) participated less. That is consistent with the hypothesis that participation in intergroup encounters facilitates dispersal and improves integration into social groups. Because extragroup matings occur in this population, both breeding females and males could be assessing neighboring individuals for mating opportunities. Resource defense and social facilitation are not mutually exclusive hypotheses, and our observations suggest that both are important components of territorial encounters in Brown Jays. Received 3 May 2002, accepted 25 November 2002.

Mercury (Hg) is a highly toxic metal that has detrimental effects on wildlife. We surveyed Hg concentrations in 10 species of bats collected at wind farms in the central United States and found contamination in all species. Mercury concentration in fur was highly variable both within and between species (range: 1.08-10.52 µg/g). Despite the distance between sites (up to 1200 km), only 2 of the 5 species sampled at multiple locations had fur Hg concentrations that differed between sites. Mercury concentrations observed in the present study all fell within the previously reported ranges for bats collected from the northeastern United States and Canada, although many of the bats we sampled had lower maximum Hg concentrations. Juvenile bats had lower concentrations of Hg in fur compared with adult bats, and we found no significant effect of sex on Hg concentrations in fur. For a subset of 2 species, we also measured Hg concentration in muscle tissue; concentrations were much higher in fur than in muscle, and Hg concentrations in the 2 tissue types were weakly correlated. Abundant wind farms and ongoing postconstruction fatality surveys offer an underutilized opportunity to obtain tissue samples that can be used to assess Hg contamination in bats. Environ Toxicol Chem 2018;37:160-165. © 2018 SETAC [ABSTRACT FROM AUTHOR]

Simple Summary: Although wind energy provides valuable environmental and economic benefits, it has unintended negative consequences for wildlife, particularly birds and bats that collide with the rotating blades. In North America, for example, there are increasing concerns that wind turbines threaten the persistence of populations of migratory tree-roosting bats, such as the hoary bat (Lasiurus cinereus). Because it is not possible to monitor population sizes for these solitary and cryptic species using traditional techniques, we must rely on other methods, such as acoustic and genetic monitoring, to provide information regarding population status and trends. Using these approaches, we can build a weight of evidence to assess whether mortality associated with wind turbines is sustainable and determine if and when mitigation measures should be implemented to reduce wind turbine mortality. To this end, we recommend that acoustic data be collected using the North American Bat Monitoring Program (NABat) protocols, and that genetic diversity be monitored at repeated time intervals to document species trends. There are no short-term measures to resolve population-level questions for migratory tree-roosting bats. Nonetheless, we discuss opportunities for relatively short-term investments that will lead to long-term success in reducing uncertainty for these species. Wind turbine-related mortality may pose a population-level threat for migratory tree-roosting bats, such as the hoary bat (Lasiurus cinereus) in North America. These species are dispersed within their range, making it impractical to estimate census populations size using traditional survey methods. Nonetheless, understanding population size and trends is essential for evaluating and mitigating risk from wind turbine mortality. Using various sampling techniques, including systematic acoustic sampling and genetic analyses, we argue that building a weight of evidence regarding bat population status and trends is possible to (1) assess the sustainability of mortality associated with wind turbines; (2) determine the level of mitigation required; and (3) evaluate the effectiveness of mitigation measures to ensure population viability for these species. Long-term, systematic data collection remains the most viable option for reducing uncertainty regarding population trends for migratory tree-roosting bats. We recommend collecting acoustic data using the statistically robust North American Bat Monitoring Program (NABat) protocols and that genetic diversity is monitored at repeated time intervals to show species trends. There are no short-term actions to resolve these population-level questions; however, we discuss opportunities for relatively short-term investments that will lead to long-term success in reducing uncertainty. [ABSTRACT FROM AUTHOR]

The article discusses a study on the sequences from three chloroplast regions from nine species of Ayenia, 27 species of Byttneria and Rayleya bahiensis with good representation of morphological diversity in both genera and sampling from their geographic ranges. Chloroplast markers from representatives of nine species of Ayenia, 27 specimens of Byttneria and the monotypic Rayleya behiensis were sequenced. The findings indicate a complex pattern of evolution of the floral characters used to circumscribe genera and sections with Ayenia and Byttneria.