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Negative effects of urbanisation on the physical condition of an endemic dung beetle from a neotropical hotspot
No full text1. Urbanisation causes important losses in biodiversity and ecosystem of animals. To test whether these negative effects are preceded by unhealthy individuals in urban populations, we evaluated the effects of urbanisation on the abundance and physical condition of the dung beetle Dichotomius guaribensis, an endemic species of the Brazilian Atlantic Forest. 2. We sampled beetles in nine forest fragments with different urbanisation degrees, embedded in the urban matrix of the city of João Pessoa. Besides testing the abundance in each fragment, we quantified four indicators of physical condition in males and females: body size, body mass, energetic condition, and mite load. 3. Females tended to be larger, and to have less lipid mass and more mites than males. Urbanisation had no effect on beetle abundance, but it negatively affected body mass and lipid content in males, but not females, revealing different sensitivities for both sexes. Body size and mite load were not affected by urbanisation in males or females. Fragment size had no effect on beetle abundance and physical condition in both sexes, suggesting that urbanisation has a greater impact than fragment size on beetle individual condition. 4. In this study, we show that individual deterioration precedes population declines in disturbed environments, and our study opens new insights into the proximate causes that leads to the loss of biodiversity and ecosystem services in urbanised regions. © 2020 The Royal Entomological Societ
An empirical evaluation of camera trap study design: How many, how long and when?
No full textCamera traps deployed in grids or stratified random designs are a well-established survey tool for wildlife but there has been little evaluation of study design parameters. We used an empirical subsampling approach involving 2,225 camera deployments run at 41 study areas around the world to evaluate three aspects of camera trap study design (number of sites, duration and season of sampling) and their influence on the estimation of three ecological metrics (species richness, occupancy and detection rate) for mammals. We found that 25–35 camera sites were needed for precise estimates of species richness, depending on scale of the study. The precision of species-level estimates of occupancy (ψ) was highly sensitive to occupancy level, with 0.75) species, but more than 150 camera sites likely needed for rare (ψ < 0.25) species. Species detection rates were more difficult to estimate precisely at the grid level due to spatial heterogeneity, presumably driven by unaccounted habitat variability factors within the study area. Running a camera at a site for 2 weeks was most efficient for detecting new species, but 3–4 weeks were needed for precise estimates of local detection rate, with no gains in precision observed after 1 month. Metrics for all mammal communities were sensitive to seasonality, with 37%–50% of the species at the sites we examined fluctuating significantly in their occupancy or detection rates over the year. This effect was more pronounced in temperate sites, where seasonally sensitive species varied in relative abundance by an average factor of 4–5, and some species were completely absent in one season due to hibernation or migration. We recommend the following guidelines to efficiently obtain precise estimates of species richness, occupancy and detection rates with camera trap arrays: run each camera for 3–5 weeks across 40–60 sites per array. We recommend comparisons of detection rates be model based and include local covariates to help account for small-scale variation. Furthermore, comparisons across study areas or times must account for seasonality, which could have strong impacts on mammal communities in both tropical and temperate sites. © 2020 North Carolina Department of Natural and Cultural Resources. Methods in Ecology and Evolution © 2020 The British Ecological Society
Echolocation of Central Amazonian ‘whispering’ phyllostomid bats: call design and interspecific variation
Full text linkPhyllostomids (New World leaf-nosed bats) are the ecologically most diverse bat family and have undergone the most extensive adaptive radiation of any mammalian family. However comprehensive, multi-species studies regarding phyllostomid echolocation are scarce in the literature despite abundant ecological research. In this study, we describe the call structure and interspecific variation in call design of 40 sympatric phyllostomid species from the Central Brazilian Amazon, focussing on general patterns within genera, subfamilies and between feeding guilds. All but one species utilized short, broadband FM calls consisting of multiple harmonics. As reported for other bat families, peak frequency was negatively correlated with body mass and forearm length. Twenty-five species alternated the harmonic of maximum energy, principally between the second and third harmonic. Based on PCA, we were unable to detect any significant differences in echolocation call parameters between genera, subfamilies or different feeding guilds, confirming that acoustic surveys cannot be used to reliably monitor these species. We present Ametrida centurio as an exception to this generalized phyllostomid structure, as it is unique in producing a mono-harmonic call. Finally, we discuss several hypotheses regarding the evolutionary pressures influencing phyllostomid call structure. © 2020, The Author(s)
Use of fructooligosaccharide in commercial diets for tambaqui (Colossoma macropomum, Serrasalmidae: Characiformes)
No full textLevantamento da qualidade ambiental do córrego capim puba no município de Goiânia - GO
Full text linkWater is an essential natural resource for the maintenance and life of humans, however, anthropogenic actions have disrupted aquatic ecosystems and threatened freshwater sources. The objective of this work was to verify the environmental quality of the Capim Puba stream, located in the city of Goiânia, state of Goiás, during the rainy season of 2016. The samples were collected in three sampling points distributed along the course of the creek: 01 located at the source, point 02 at the site of greater anthropic occupation of the stream banks and point 03 at the confluence with the Botafogo Stream. Environmental quality was investigated through the identification of domestic and industrial effluent release points, level of silting, presence of erosion, debris, flora, solid residues and liquid residues, as well as analysis of physical and chemical variables of the aquatic environment. It was possible to notice greater environmental degradation in point 02 due to anthropic occupation. In addition, the adverse impacts were less intense when compared to previous years, revealing a capacity of the autodepuration stream. © 2020 Centro Universitario de Anapolis. All rights reserved
Leaf isoprene and monoterpene emission distribution across hyperdominant tree genera in the Amazon basin
No full textTropical forests are acknowledged to be the largest global source of isoprene (C5H8) and monoterpenes (C10H16) emissions, with current synthesis studies suggesting few tropical species emit isoprenoids (20–38%) and do so with highly variable emission capacities, including within the same genera. This apparent lack of a clear phylogenetic thread has created difficulties both in linking isoprenoid function with evolution and for the development of accurate biosphere-atmosphere models. Here, we present a systematic emission study of “hyperdominant” tree species in the Amazon Basin. Across 162 individuals, distributed among 25 botanical families and 113 species, isoprenoid emissions were widespread among both early and late successional species (isoprene: 61.9% of the species; monoterpenes: 15.0%; both isoprene and monoterpenes: 9.7%). The hyperdominant species (69) across the top five most abundant genera, which make up about 50% of all individuals in the Basin, had a similar abundance of isoprenoid emitters (isoprene: 63.8%; monoterpenes: 17.4%; both 11.6%). Among the abundant genera, only Pouteria had a low frequency of isoprene emitting species (15.8% of 19 species). In contrast, Protium, Licania, Inga, and Eschweilera were rich in isoprene emitting species (83.3% of 12 species, 61.1% of 18 species, 100% of 8 species, and 100% of 12 species, respectively). Light response curves of individuals in each of the five genera showed light-dependent, photosynthesis-linked emission rates of isoprene and monoterpenes. Importantly, in every genus, we observed species with light-dependent isoprene emissions together with monoterpenes including β-ocimene. These observations support the emerging view of the evolution of isoprene synthases from β-ocimene synthases. Our results have important implications for understanding isoprenoid function-evolution relationships and the development of more accurate Earth System Models. © 2020 Elsevier Lt
Special issue in honour of Prof. Reto J. StrasserChlorophyll a fluorescence of Bertholletia excelsa Bonpl. plantations under thinning, liming, and phosphorus fertilization
No full textA molecular and morphological approach on the taxonomic status of the Brazilian species of Palaemon (Decapoda, Palaemonidae)
No full textPrevious studies have indicated the occurrence of nine species of Palaemon in Brazil. However, the extensive variability in their diagnostic characters and the geographic distribution of some species raises doubts about the validity of some taxa, potentially indicating the occurrence of species not yet reported from Brazil or even not described. To solve taxonomic issues with Palaemon species in Brazil, we carried out a multigene analysis by using partial fragments of 16S and COI mitochondrial genes and the nuclear H3. Phylogenetic relationships were inferred by maximum likelihood and Bayesian inference. The external morphology corresponding to the terminal clades obtained in the molecular phylogram was analysed to identify diagnostic characters that allow the recognition of the groups and the correct taxa assignment. The combined analysis of molecular and morphological data confirms the existence of nine species of Palaemon in Brazil, five from the “Palaemon” lineage (P. mercedae and four Palaemon stensu stricto—P. argentinus, P. octaviae—first record in Brazil, P. northropi and P. paivai) and four of the “Alaocaris” lineage (P. carteri, P. ivonicus, P. pandaliformis and P. yuna). The possibility of further cryptic speciation is also pointed out. In addition to confirming the validity of the nine species, the results indicate the need for taxonomic adjustments and corresponding changes in the geographic distribution of Palaemon species occurring in Brazil. © 2019 Royal Swedish Academy of Science