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The breeding success of birds can be influenced by habitat characteristics (e.g., vegetation cover and weather), species interactions (e.g.. predation and parasitism), and species' intrinsic factors (e.g.. behavior and nest structure and location). Information about breeding traits is crucial to better understand population dynamics. Here, we performed probabilistic modeling of Dark-billed Cuckoo (Coccyzus melacoryphus) nests to assess the effect of habitat and nest parameters (e.g., time, season, nest site, clutch size, and brood size) on daily survival. We carried out this study in northeastern Brazil during the rainy seasons (Jan-Jun) of 2017 and 2018. To assess daily nest survival and the effects of habitat and nest covariates, we located and monitored 61 nests every 2-3 d following the Mayfield protocol and analyzed these data using information-theoretic model-selection program MARK. We found a higher daily survival during incubation than during the nestling period, with a positive effect of clutch and brood size. Models constrained by the covariates year, breeding season time, species of plant supporting the nest, nest height, and nest concealment were not supported. Success for the incubation and nestling periods were 19% and 11% by Mayfield. and 33%, and 4% by MARK model averaging. corresponding to a total nest-period success of 2.1%: and 1.5% for each method, respectively. The positive relationship found between survival and clutch size for the Dark-billed Cuckoo seldom occurs in birds from tropical regions. As expected for tropical birds, we recorded high predation and low breeding success. Received 15 April 2021. Accepted 2H September 2022. Key words: Caatinga. daily survival rates. Program MARK, predation. reproductive success. O sucesso reprodutivo de aves pode ser influenciado por caracteristicas do habitat (como cobertura vegetal e elima). interacao de especies (predaeao e parasitismo) e fatores intrinsecos da especie (comportamento, estrutura e localizacao do ninho). Informacoes sobre as caracteristicas de reproducao das aves sao cruciais para entender melhor a dinamica das populacoes. Execulamos modelagens probabilistieas e eslimamos a sobrevivencia do ninho do Coccyzus melacoryphus para verificar o cfeito dos parametros do habitat e dos ninhos (tempo, estacao reprodutiva. local do ninho. tamanho da postura e da ninhada). Realizamos o estudo no Nordeste do Hrasil durante as estacocs chuvosas (Janeiro-junho) de 201 7 e 2018. Para estimar a sobrevivencia dos ninhos. os efeitos do habitat e das covariaveis do ninho. localizamos e monitoramos 61 ninhos em intervalos dc 2-3 dias seguindo o protocolo de Mayfield e analisamos os dados atraves do programa de selecao dc modelos probabilisticos MARK.. A modelagem mostrou maior sobrevivencia durante a ineubacao quando comparado ao periodo de filhotes. com eteito positivo do tamanho da postura e da ninhada. Enconlramos uma maior sobrevivencia diaria durante o periodo dc ineubacao do que o periodo de ninhego. com um cfeito positivo do tamanho da postura e da ninhada. Os modelos limitados pelas covariaveis ano. epoca da estacao reprodutiva. suportc da planta. altura e eamuflagcm do ninho nao foram suponados. O sucesso para os periodos de ineubacao c ninhego foi de 19% e 11 % por Mayfield, 33% e 4% pela media do modclo MARK, correspondendo a am sucesso reprodutivo total de 2,1% e 1,5% para cada metodo, respectivamente. A relacao positiva encontrada entrc a sobrevivencia e o tamanho da postura para o C melacoryphus raramentc ocorrc em aves de regioes tropicais. Como esperado para aves tropicals, registramos alta predaeao e baixo sucesso reprodutivo. Palavras-chave: Caatinga. predaeao. Programa MARK, sucesso reprodutivo. taxas dc sobrevivencia diarias., The basis of the avian life history and breeding ecology theory is founded primarily on data from temperate species that only includes a few tropical examples, although tropical habitats and [...]

The release of carbon dioxide (C[O.sub.2]) occurs through soil respiration. However, release of C[O.sub.2] from soil to the atmosphere is subject to interference from agents such as relief, edaphic and climatic conditions. Thus, this research aimed to quantify edaphic respiration related to edaphoclimatic factors in a toposequence area in Caatinga of Delmiro Gouveia, Alagoas, Brazil. The research was conducted from February 2013 to June 2014, with bimonthly collections during day and night. The soil C[O.sub.2] losses, temperature measurements, soil water content and rainfall were quantified. We verified that, independent of the evaluated points, C[O.sub.2] release was higher at night. Half-slope and shoulder were the areas with the highest emissions. Additionally, the C[O.sub.2] emissions presented annual variation, increasing with the availability of soil water and showing peaks of release in the rainy season. Soil and air temperature had no direct influence on soil C[O.sub.2] release; however, the highest C[O.sub.2] emissions occurred when temperatures were moderate and stable. Therefore, the conservation of this unique Brazilian biome is necessary because the impacts of its disturbance can increase the level of C[O.sub.2] released from the soil, increasing the amount of C[O.sub.2]in the atmosphere. Additional keywords: Brazilian semi-arid, rainfall, soil carbon dioxide, soil moisture, soil temperature. Received 12 June 2019, accepted 9 December 2019, published online 3 February 2020, Introduction Caatinga is the predominant vegetation type of the semi-arid region of north-eastern Brazil. Due to its heterogeneity and the significant number of rare and endemic species in the Caatinga, [...]

Habitat area and fragmentation are recognised as important factors that influence population size, community structure and extinction risk. Abundance and species richness universally increase with habitat area. However, the effects of different aspects of habitat fragmentation, including variation in patch size, number and isolation are often not distinguished from each other or the overall effects of habitat amount. Here we experimentally tested predictions concerning the effects of isolation on abundance, species richness and community structure of coral reef fishes colonising patch reefs by constructing clusters of patches of the same number and size, but manipulating reef spacing. Hexagonal clusters of 7 experimental patch reefs (6 edge and 1 central) with 3 levels of isolation (1 m, 5 m, and 15 m spacing) were established at Kavieng, Papua New Guinea and colonisation was recorded after 6 weeks in 2014. We also deployed video cameras to test whether isolation affected the activity of transient predatory fishes. As predicted, isolation had a positive effect on both mean abundance and species richness at both the cluster and patch scale. The cumulative abundance and species richness exhibited linear increases in relation to habitat area within clusters (from 1 to 7 patch reefs), but the slope increased with the degree of isolation. There was some evidence that transient predators remained longer and were more successful when patches were close together, which may explain the lower abundance and richness of juvenile fish assemblages on more aggregated patch reefs. This study demonstrates that while habitat amount is fundamentally important, isolation has significant effects that will need to be distinguished from other aspects of fragmentation when examining the processes structuring reef fish communities., Author(s): G. P. Jones [sup.1] [sup.2], G. Barone [sup.1] [sup.3], K. Sambrook [sup.1] [sup.2], M. C. Bonin [sup.1] [sup.2] [sup.4] Author Affiliations: (1) grid.1011.1, 0000 0004 0474 1797, College of [...]

Contemporary problems are often complicated by values intruding into the arena of material systems. But there have always been values in biology and social science because they are required to assess how biosocial structures have models embodying purpose as an issue separate from the models of the scientists. Values are addressed seriously in economic discourses, and other discussions will benefit from paying attention to how the dismal science does that. Economic notions of profit have values embedded in them in a way that generally does not occur in ecology and the other natural sciences. Here we generalize profit as gain in settings beyond strict economics in a way that encourages placing values properly in biological and historical social systems. Complications of elaborate control quickly enter the scene at this point and in this paper we invoke hierarchy theory to keep levels of analysis straight. Hierarchy theory often invokes dualities and a mix of process and structure that is fluid under changes in level of analysis. Beyond this, the things the hierarchy represents changes over time, so we must extend discourse of level of analysis to include how time forces the use of new levels of analysis as hierarchies change over time. Notions of gain and profit are recursive as the system uses resources and must change strategies to deal with scarcity. This in turn forces increases in efficiency in yet a new round of change. The transition from abundant resources used carelessly to scarce resources used efficiently changes controls in biosocial systems. Such changes over time amount to hierarchical restructuring, which in turn requires of the observer meticulous application of new levels of analysis as the system is redefined. The system bounded at a new hierarchical level encounters dualities embedded in the hierarchical concept of the holon. The holon offers a precision of definition of the new system as it exists as an autonomous whole while still being part of some larger system. We introduce these shifts and dualities using examples from nuclear energy, colonial insects and changes in complex societies such as the Roman Empire and the EU. In the end both ideas of profit and hierarchy theory are clarified in a two-way exchange that moves forward our understanding of biosocial systems. Keywords ants; duality; EROEI; hierarchy; high gain; holon; level of analysis; low gain; resources; societal collapse; termites, INTRODUCTION The critical complication in biological and social system research is that the scientists' models address entities that themselves have models for the world (Rosen, 1979). The object of study [...]