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This study aimed to understand the reproductive biology and migrative behavior of the largehead hairtail Trichiurus lepturus in a tropical area, specifically off Pernambuco coast, northeastern Brazil. Commercial catches from fish corrals provided samples for analysis, including measurements, weight recording, and examination of gonads to determine its maturation stage. Reproductive analyses were performed, such as sex ratio, gonado‐somatic index, and sizes at first maturity. There was a slightly higher proportion of females among the 141 largehead hairtail specimens analysed. No significant differences were observed in length distributions between males and females. However, during the winter, significant differences were observed in length distributions for grouped sexes. The species exhibited a seasonal migratory pattern, with a higher presence on the continental shelf during the winter. The study identified strategic allocation of energy in feeding activities and temporal spacing of reproductive cycles, as indicated by the sex ratio and abundance of individuals during different seasons. Fish corrals probably do not harm largehead hairtail population off the southwestern Atlantic tropical coast, with minimal capture of individuals below the size of first maturity. The insights of the study into reproductive and migration patterns contribute to future assessments and management strategies for this species and corral fisheries. [ABSTRACT FROM AUTHOR]

Natural history studies are important in helping to understand the origin and evolution of social organization as well as the evolution of specialized morphological structures linked to mating behavior of animals. Here we describe the burrow use pattern, sex ratio, and sexual dimorphism of the burrowing shrimp Lepidophthalmus siriboia to test a series of evolutionary hypotheses. To this end, a total of 259 individuals of L. siriboia were collected from the northeast region of Brazil. No shrimp pairs or burrows inhabited by more than one shrimp were detected during the study period. A solitary habit is a non-random behavior in this species because single shrimps were found with a greater frequency than expected by chance. All ovigerous females were found living solitarily, which suggests that males abandon these females shortly after insemination. Contrary to the expectations of an anisogamous species, L. siriboia produced a female-biased operational sex ratio (OSR), contradicting the hypothesis that only males compete for mates. The latter was supported by the existence of sexual dimorphism in cheliped size, a condition that argues in favor of female–female competition in this species. In the same line of reasoning, heterochely was present in adult males, although it was also present to a lesser degree in adult females. Female asymmetry of chelipeds suggests the evolution of an unconventional role in female major cheliped use. The major cheliped showed a positive allometric growth pattern through the ontogeny of both sexes. However, when growth patterns of the major and minor chelipeds were compared, the fitted regression lines for each sex had different slopes, indicating that the cheliped could be an appendage sexually selected by individuals of the opposite sex during mating. [ABSTRACT FROM AUTHOR]

We investigated the population structure, reproduction, growth parameters and total mortality of Fragillianassa fragilis. Sampling was performed monthly from July 2017 to July 2018 at Casa Caiada Beach, Pernambuco, northeastern Brazil. The overall sex ratio was 1:1 but with a dominance of juvenile males and adult females. The carapace length (CL) ranged from 1.36 to 6.59 mm for males, 1.7 and 6.05 mm for females and 3.07 and 6.14 mm for ovigerous females. Reproduction was seasonal, with peaks during the warmest months of the year. The number of eggs ranged from 20 to 259. Growth parameters for males (L ∞ = 7 mm, K = 0.95 year–1, C = 0.4, and WP = 0.5) and females (L ∞ = 6.5 mm, K = 1.0 year–1, C = 0.9, and WP = 0.75) were quite dissimilar when compared to other ghost shrimps. Mortality was considered high for males and females (2.66 and 3.41, respectively), while the Growth Performance Index (Φ') was similar for males (1.668) and females (1.626). This study provides new ecological information on ghost shrimp life-history strategies, as well as subsidies for conservation measures for this group, which is an important component of secondary production in coastal ecosystems. [ABSTRACT FROM AUTHOR]

In general, chelonians are widely distributed, occupying areas with significant environmental variation, which may lead to great variations in their ecology such as morphological characteristics, sexual dimorphism, population structure, and reproductive aspects. In this context, our main objective was to characterize populations of Phrynops geoffroanus and Mesoclemmys tuberculata in areas of Caatinga and Atlantic Forest in Northeast Brazil to evaluate the relative importance of intraspecific factors and environmental differences in determining ecological parameters. Samples were collected in semiannual surveys (dry and rainy season) over a year. We measured morphometric variables and the mass of captured animals and correlated the reproductive pattern with the season and adults' reproductive condition. We did not find significant differences in size, maximum straight-line carapace length (SCL), or body mass of both species, regardless of sex, between the studied environments. We recorded reproductive males of both species throughout the year (dry and rainy seasons), and testicular volume was positively correlated with SCL. In contrast, eggs and oocytes were recorded exclusively in females collected during the rainy season. However, we found eggs and vitellogenic follicles simultaneously, indicative of multiple clutches in a reproductive season. In P. geoffroanus, we did not find a significant relationship between clutch size and female SCL, although egg volume was positively correlated with SCL. In M. tuberculata, we did not find a meaningful relationship between any of these parameters. Finally, the ecological parameters evaluated differed considerably between species and environments, presenting similar patterns in Caatinga and Atlantic Forest. [ABSTRACT FROM AUTHOR]

Sharks are among the marine organisms most impacted by intense fisheries, a worrying fact since they are key components in the trophic structure of ecosystems. In this context, fish landing data can help managers in shark conservation. This study characterized the landings of Carcharhinus acronotus, Mustelus cf. canis, and Sphyrna mokarran in the Mucuripe Embayment, Ceará, Brazil, along three study periods (1998-1999, 2006-2008, and 2015-2016). A total of 223 specimens were recorded from 227 site visits. Carcharhinus acronotus specimens measured from 50 to 139 cm in total length (TL), with a 1.3:1 sex ratio in favor of males. Most of the specimens recorded were adults (55.1% of males and 62.9% of females). Mustelus cf. canis varied from 64 to 133 cm in TL, with a sex ratio in favor of females (3.1:1). Most of the specimens recorded were adults (50% of males and 68% of females). Sphyrna mokarran specimens varied from 116 to 380 cm in TL, with a sex ratio of 7:1 in favor of males. Most of the specimens recorded were juveniles. This is the first fishery-dependent study to provide information on size and sex composition of these species for most of the southwestern equatorial Atlantic. [ABSTRACT FROM AUTHOR]

Introduction: Uniform chromosome abnormalities are commonly seen in early pregnancy loss, with analyses of the product of conception suggesting the presence of mosaic autosomal trisomy in ∼10% of cases. Although chromosomal mosaicism occurs in a minority of embryos, their relative commonality and uncertainty regarding associated transfer outcomes have created discussion at both the clinical and research levels, highlighting the need to understand the clinical conditions associated with the incidence of embryo mosaicism. Methods: We took advantage of a preimplantation genetic testing for aneuploidy (PGTA) database created from2019 to2022inmore than 160in vitrofertilization (IVF) clinics in Brazil, the second-largest worldmarket for IVF. We carried out descriptive statistical and associative analyses to assess the proportions of mosaicism associated with clinical conditions and reported incidence by chromosome, clinic origin, and biopsy operator. Results: Chromosomal analysis revealed thatmostmosaic aneuploidies occurred in the last three chromosomes, with 78.06% of cases having only one chromosome affected. Low mosaicism in trisomy represented the most ordinary form, followed by low mosaicism in monosomy. We identified associations between low (negativelyassociated) and high mosaicism (positively-associated) and maternal age, indication (male factor and uterus/ovarian factor negatively associated with low and high mosaic, respectively), day of blastocyst development (day five has an overall better outcome), morphology grade (lower quality increased the chances of low and high mosaicism), origin (vitrified oocyte and embryo increased the rates of low and high mosaicism, respectively), and embryo sex (male embryos negatively associated with low mosaic). Discussion: With these results, we hope to foster an improved understanding of the chromosomal mosaicism linked with distinct clinical conditions and their associations in Brazil. [ABSTRACT FROM AUTHOR]

Simple Summary: For the majority of tropical birds, basic life history information is still missing and holds mostly for tropical forest species. Among these are the members of guans, chachalacas, and curassows, a New World avian family known as cracids. In our study, conducted in a protected area in the northeastern Pantanal of Brazil, where human impacts were low, we investigated the seasonal activity, social organization, and sex ratio of the Bare-faced Curassow using camera traps. Strong seasonal inundation pulses are characteristic of the study area and influence vegetation, resource, and water seasonality, causing differences in seasonal activity behavior patterns. The daily activity of the Bare-faced Curassow differed between forest- and savanna-dominated areas but did not differ by sex, seasonal period, or presence of offspring. Such population studies in protected areas may serve as a "template" to plan more appropriate conservation and area management strategies that are applicable locally and beyond. Among Neotropical cracids (Galliformes), many taxa are declining rapidly in population size and facing local extinction. However, in the Brazilian Pantanal, several species occur sympatrically and in abundant numbers to allow for long-term studies. Therefore, the study was intended to collect data and statistically evaluate the life history patterns of Bare-faced Curassow (Crax fasciolata), a high-conservation-priority species. Additionally, the effect of applying commonly used independence filters on camera trap data was evaluated. The study was conducted in the SESC Pantanal, Baía das Pedras, Mato Grosso, Brazil, a private protected area of approximately 4200 ha. Between July 2015 and December 2017 (4768 sampling days), 37 sampling locations were monitored with camera traps placed in a regular grid with a spacing of 1 km. Crax fasciolata was detected at 26 (70.27%) of them, with 357 independent captures (554 individuals). Capture success differed among the four seasonal periods, being highest during the receding and lowest during the high-water period. The seasonal difference was more pronounced in the savanna, with significantly lower activity during the rising period and higher activity during the receding period, while it was more uniform in forest-dominated areas. Groups with offspring were more active during the period of receding water, indicating the peak of reproductive activity in the months before. The daily activity of the species followed a bimodal pattern, with peaks between 06:00 and 07:00 and 16:00 and 17:00. Daily activity rhythms were similar when compared between seasonal periods, sexes, and adults with or without offspring and differed between two habitats (more homogeneous in the forest). The mean detected group size was 1.55 ± 0.81 SD, with four animals exhibiting the largest observed aggregation. Larger unisexual aggregations of adults were not observed. The offspring sex ratio was significantly female-skewed at 0.51:1.00, while the adult sex ratio was considered equal at 1.05:1.00 (male:female). The use of different independence filters did not alter the BFC general activity pattern estimates. Cracids can be considered important bioindicators of habitat quality. The results of this study outline the importance of the Pantanal as a stronghold for this species and the privately protected areas with low anthropogenic activity as highly beneficial to its populations. [ABSTRACT FROM AUTHOR]

Some Aedinii mosquitoes are of high importance in the transmission of the sylvatic YFV. Usually, their eggs are very resistant and depend on the rain for their hatching. The present study evaluated the effect of multiple mosquito-egg immersions and the sex ratio of male and female specimens from Atlantic Forest remnants in the state of Rio de Janeiro, Brazil. Three sampling sites were selected in the municipality of Casimiro de Abreu, where 50 ovitraps were randomly installed to collect eggs from the ground level up to different heights, from August 2018 to December 2020. The mosquito sex ratios were compared between seasons and forest sites, using the generalized linear mixed model (GLMM), which included sampling months and trees as random effects. A total of 33,091 mosquito eggs were collected, of which 6152 eggs were already hatched (18%) and 26,939 were unhatched; of these, approximately 76% subsequently hatched. We found that 25% of the eggs corresponded to four species: Aedes albopictus (n = 1277), Ae. terrens (n = 793), Haemagogus janthinomys (n = 89), and Hg. leucocelaenus (n = 3033). The sex ratio (male:female) was variable concerning the sampling sites and the season. For most species, GLMM estimates found no difference in the variation of the average sex ratio as a function of these predictors, and there was no evidence of temporal autocorrelation in the mosquito data. The number of immersions necessary for hatching the eggs differed between mosquito species, and eggs collected in the dry season hatched both in the first immersions and the subsequent events. Co-occurrence of Aedes terrens and Hg. leucocelaenus was the most frequently observed pairwise species combination. Considering recurrent arbovirus outbreaks in Brazil and their burden on the human population, our study helps to shed light on how these vectors behave in nature; therefore, they can be used in surveillance programs. [ABSTRACT FROM AUTHOR]

This study aimed to estimate the parameters of length-weight relationship, sex ratio, and diet of three freshwater fish species that inhabit streams in the Pomba River basin (Rio de Janeiro, Brazil). Fishes were sampled with seine nets (2.0 x 1.20 m, 2 mm mesh size) and dip nets (0.46 x 0.33 m, 2 mm mesh size) from October to December 2018. Measurements were taken for total length (TL -- 0.1 cm precision) and total weight (TW -- 0.01 g precision). Growth model parameters were estimated. This study provides new length-weight relationship data for Deuterodon intermedius (Eigenmann, 1908), Australoheros paraibae Ottoni & Costa, 2008, and Hypostomus punctatus Valenciennes, 1840. All of them ingested a wide variety of food items, including plant material like algae, animal material such as terrestrial and aquatic insects, and undefined matter such as detritus or mud. The three species showed a higher number of females. Our study provides basic information for functional diversity studies, as well as for future investigations associated with the evaluation of anthropic impacts, either occasional or chronic, on the fish assemblage structure of the Pomba River basin. [ABSTRACT FROM AUTHOR]

BACKGROUND Age misreporting affects population estimates at older ages. In Brazil, every citizen must be registered and show an identity document to vaccinate against COVID-19. This requirement to present proof of age provides a unique opportunity for measuring the oldest-old population using novel administrative data. OBJECTIVES To offer critically assessed estimates of the Brazilian population aged 80 and older based on data from the vaccination registration system (VRS). To uncover discrepancies between the number of vaccinated oldest-old people and the projections used to estimate target populations for COVID-19 vaccination. METHODS We calculate data quality indicators based on data from the VRS - namely, 100+/80+ and 90+/80+ population proportions, sex ratios, and the Myers blended index - and compare them to those based on data on target populations from Brazilian censuses and demographic projections, and from Sweden - a country with high-quality data. We also estimate vaccination coverage ratios using population projections adjusted to excess deaths as the denominators. RESULTS Requiring documentation reduces age heaping, age exaggeration, and sex ratios marginally. However, it cannot solve the problem of the misreporting of birth dates due to the absence of long-standing birth registration systems in Brazil, particularly in the northern and central regions. In addition, we find a mismatch between the projected populations and numbers of vaccinated people across regions. CONCLUSIONS Despite improvements in data quality in Brazil, we are still not confident about the accuracy of age reporting among the oldest old in the less advantaged Brazilian regions. The postponement of the 2020 census reduced the ability of authorities to define the target populations for vaccinations against COVID-19 and other diseases. CONTRIBUTIONS This is the first study to compare population estimates for the oldest old in administrative data and census data in Brazil. Age misreporting resulted in discrepancies that may have compromised the efficacy of the COVID-19 vaccination campaign. [ABSTRACT FROM AUTHOR]

Many ecological questions can be answered only with data from hundreds or even thousands of individuals. In some taxonomic groups, such as snakes, the availability of those data is rare due to low population densities and/or the difficulties in collecting them. Hence, studies on the population structure of snakes are still relatively scarce compared to other zoological groups. In this study, we had the opportunity to analyze the population structure from an unusually large sample of the Pampean water snake Helicops infrataeniatus. The specimens were collected through a flood event caused by excessive rainfall related to an El Niño period in southern Brazil. Although H. infrataeniatus is a common species in the study area, no ecological data regarding its population structure are available so far. Therefore, the main goals of this study were to (1) determine sex ratios, (2) test for sexual dimorphism, and (3) identify the ventral polymorphism in this population. We analyzed 672 individuals (46.4% females, 53.6% males; 50.2% were classified as adults, 48.6% juveniles, and 1.3% hatchlings). The total body length (ToL) ranged from 18.4-77.4 cm for females, and 19.7-67.0 cm for males, tail length (TaL) was 4.5-21.9 cm and 5.8-21.5 cm; sub-caudal scales were 55-73, 74-92, and weight was 2.2-191.0 g, 2.3-93.3 g. Highly significant differences were detected in the number of sub-caudal scales and the TaL:ToL ratios between females vs. males tested via analysis of covariance (ANCOVA), suggesting the presence of sexual dimorphism. Regarding the ventral spotting patterns, 38.0% of individuals had trilinear, 36.0% - intermediate, and 26.0% - checkered color patterns. Besides this, 63.0% of the individuals had a reddish ventral coloration, 25.0% - yellowish, and 12.0% - both colors. No correlation was found between ventral polymorphism and sex or age class. The results presented herein offer the first robust snapshot of the population structure of H. infrataeniatus. [ABSTRACT FROM AUTHOR]

We investigated demographic changes in three primate species (Alouatta guariba, Sapajus nigritus, and Callithrix flaviceps) at the Reserva Particular do Patrimônio Natural–Feliciano Miguel Abdala, Caratinga, Minas Gerais, Brazil, following a yellow fever outbreak (YFO) by comparing their population sizes before (2015) and after the outbreak (2017–2018), and by monitoring the size, composition, and reproductive status of groups from 2017 to 2021. Comparisons of pre‐ and post‐YFO census data indicate the A. guariba population declined by 86.6%, from an estimated minimum of 522 individuals to 70 individuals. However, by October 2021, the population had grown to at least 86 individuals, with an adult sex ratio (N = 53) that was female‐biased (0.61). Eleven of the 13 groups being monitored systematically were reproductively active with high survivorship to 12 months of age. S. nigritus declined by 40%, from 377 to 226 individuals. The sex ratio of 33 adult S. nigritus is also female‐biased (0.71), and at least 8 of 15 groups being monitored are reproductively active. C. flaviceps declined by 80%, from 85 individuals to the 15–17 individuals observed from 2017 to 2021. The female‐biased adult sex ratio and presence of infants and juveniles in the A. guariba and S. nigritus groups are encouraging signs, but there is still great concern, especially for C. flaviceps. Continued monitoring of the demographics of these primates is needed as their persistence appears to still be at risk. Research highlights: This study documented an unprecedent decline in three endemic primate species following a severe yellow fever outbreak in the Brazilian Atlantic Forest.Adult female biased sex ratios and reproductive activity suggest at least two species may be recovering from the drastic demographic changes. [ABSTRACT FROM AUTHOR]

The density and age structure of spider populations are affected by biotic and abiotic factors. The orb-web spider Eustala taquara (Araneidae) lives camouflaged on the dead vegetation of shrubs, especially in forest edges. Here, we describe the variation in the number of individuals over the year and the phenology of a population of E. taquara. We also tested whether these variables are influenced by temperature, precipitation or prey availability. We conducted the research in a tropical rainforest located in south-eastern Brazil. We recorded the number of spiders and their development stages (spiderling, young, juvenile, sub-adult and adult) monthly, for two years, along 1 km at the forest edge at an altitude of 1000 m above sea level. We estimated prey availability using 20 circular transparent plates containing tanglefoot on one side, exposed for 48 hours in the vegetation, sampled monthly for 18 months. We used circular statistics to assess the peaks of individuals during the study period, verifying the occurrence of time lags between the number of spiders with the climatic variables and prey availability. The population of E. taquara increased in periods of lower precipitation and temperature, and decreased during the rainy season. Thus, the population showed a negative correlation with the climatic variables and potential prey availability. All instars were present simultaneously, revealing that spiders can reproduce at any time of year. During the dry season, the higher number of spiders may be related to the increase in branches and dead plants that provide camouflage against visually oriented predators and sites for web building, increasing the likelihood of obtaining food. [ABSTRACT FROM AUTHOR]

The porcelain crab Pachycheles laevidactylus is the most frequent crustacean decapod in the polychaeta sandbanks in some Brazilian locations; however, the only populational data available for this species are from Argentina. Here, we analysed the population structure, sex ratio, reproductive period, size at sexual maturity (functional and morphological) and relative growth of this species from two locations in southern Brazil. The crabs were collected seasonally during one year, sexed, counted and measured. A total of 1534 individuals were sampled, 943 in Torres and 591 in Tramandaí. There was no difference in cheliped size between sexes, while females were larger and had larger pleons than males, and this difference is related to reproduction. The sex ratio was 1:1 in both locations throughout the year. Ovigerous females were found in all seasons, with a higher frequency in the coldest seasons, but the presence of megalopae occurred exclusively in spring. The morphological sexual maturity for females was larger than the size of the smallest ovigerous female collected, as already reported for other decapods. Overall, the species starts reproducing at smaller sizes at locations closer to the edges of its distribution (northern Brazil and northern Argentina). Some differences in relative growth were found between males and females, adults and juveniles, and the implications of these differences are discussed. This study brings the first populational data of P. laevidactylus from Brazil over a year, which was compared with available studies of Porcellanidae and will be useful for comparison with future studies in tropical areas, to better understand how the biological aspects of this species vary along its wide distribution in the south‐western Atlantic. [ABSTRACT FROM AUTHOR]

Our knowledge of the mating systems in burrowing shrimps (infraorders Axiidea and Gebiidea) is still rather limited. Here we describe the burrow use pattern, sex ratio, and sexual dimorphism of the burrowing shrimp Axianassa australis to test for monogamy, considering that monogamous species live in heterosexual pairs and exhibit a low degree of sexual dimorphism. To this end, a total of 226 individuals of A. australis were collected from the northeast region of Brazil. Our results showed that A. australis inhabited its burrows mainly as pairs, most of which were male-female pairs. In agreement with the expectations, specimens of A. australis were found dwelling as heterosexual pairs more frequently than expected by chance alone. The presence of ovigerous females was associated with the burrow occupation; that is, brooding females were more frequently observed in male-female combinations than solitarily. Also supporting theoretical considerations, we did not observe sexual dimorphism in body size between males and females of the population and the different categories of the burrow occupation. Conversely, sexual dimorphism in cheliped size was evident in the population, with larger chelipeds in males than in females. This observation agrees with that reported for most burrowing shrimps in which male-male competition is the main evolutionary force of sexual selection. The observations above favor the hypothesis that A. australis is primarily monogamous, with a small fraction of the males moderately promiscuous. [ABSTRACT FROM AUTHOR]

Mourecotelles Toro & Cabezas (Hymenoptera, Apidae, Colletinae) currently includes only nine valid species of cellophane bees found mostly in relatively-dry regions of western South America (Chile, Argentina, Bolivia, and Ecuador). In this paper, we describe and illustrate a new species of the genus - M. braziliensis Ferrari & Melo, sp. nov. - based on individuals of both sexes captured through trap-nesting in an environmental protection area (Araucárias Municipal Natural Park) and in flowers in different localities in southern Brazil. In total, we obtained 16 nests of M. braziliensis, each consisting of two to eleven brood cells arranged horizontally and lined with a cellophane-like substance. Of the 57 adult bees that emerged, 41 were male (mean weight 46.5 mg) and 16 were female (mean weight 58.9 mg), resulting in biased sex and investment ratios of 2.56:1 and 2.02:1, respectively. Both the numbers of provisioned cells and mortality rate were higher for trap nests with the narrowest bore diameter, although the differences in relation to other trap nests were not statistically significant. Pollen of nine different plant families were found in brood cells of M. braziliensis, but the species showed a clear preference for Fabaceae and Polygalaceae. Indeed, some of the specimens were collected while foraging in flowers of an unidentified species of Monnina Ruiz & Pav. (Polygalaceae) growing in swampy areas. The evolutionary and biogeographical implications of our discovery are briefly discussed. [ABSTRACT FROM AUTHOR]

The migratory behavior of freshwater shrimps may be affected by natural barriers in limnetic environments. This study evaluated the river areas separated by natural barriers, such as waterfalls, which affect the amphidromous shrimps' (Potimirim brasiliana) population features and reproductive aspects. Results indicate that in the Félix and Prumirim Rivers from southeastern Brazil shrimps show few differences in sampling areas, and these differences may not be causally related to the waterfalls. This is demonstrated by the absence of a pattern in the size and sex ratio in each area and the absence of a significant difference in most reproductive aspects. The presence of juveniles and reproductive individuals in all sampling areas strongly indicates a constant migration along them in both rivers, indicating that all individuals evaluated correspond to one single patchy population structure for each river. This migration conducted by P. brasiliana , such as its crawling behavior, demonstrated that it would be important to maintain the minimum number of individuals flowing between the different river sampling areas in this shrimp group. Thus, based on a helpful model observed in P. brasiliana , the results help us understand how natural barriers may affect the populations of amphidromous shrimp and how the migration behavior up- and downstream can help sustain the population. This premise can help future construction decisions and impacts of unnatural barriers, such as dams. [ABSTRACT FROM AUTHOR]

Bats are parasitized by many different arthropods, among which the dipteran families Nycteribiidae and Streblidae are exclusive to bats. Researches that relate the ecology of ectoparasites with their hosts are fundamental for understanding issues related to the interactions between these two groups, in addition to epidemiological aspects of pathogen transmission. The present study evaluated the rate of infestation by dipteran (Streblidae) ectoparasites in two colonies of Anoura geoffroyi associated with caves in the southeastern Brazil. It also evaluated whether parasitological indices differ significantly with regard to host sex and reproductive condition. A total of 1377 bats were captured, of which 84% were parasitized. From these, a total of 5047 streblid bat flies belonging to three species of three genera were collected and identified. The most abundant was Exastinion clovisi (57%), followed by Anastrebla modestini (30%) and Trichobius propinquus (13%). In general, the populations of ectoparasites fluctuated throughout the year, with peaks of abundance during the rainy season. The sex ratios for the species of ectoparasites were close to one, which differs from what is reported in the literature. In addition, there were significant differences in parasitism rates in relation to host sex and reproductive condition. In both populations, ectoparasite infestation of pregnant or lactating females was significantly higher than for non-reproductive females. New studies aimed at assessing whether these higher rates of infestation have any effect on female bat reproduction are needed. [ABSTRACT FROM AUTHOR]

Palpita forficifera Munroe (Lepidoptera: Crambidae) is the principal pest in olive groves in Brazil and Uruguay, damaging buds and fruits. Therefore, this work was undertaken to understand the biology of P. forficifera at different temperatures, to determine thermal requirements, and to estimate the number of annual generations in different olive groves located in Brazil and Uruguay. The study was performed at 10, 15, 20, 25, 30, and 35 °C, 60 ± 10% RH, and a 14:10 h (L:D) photoperiod. The duration and survival stages of development, sex ratio, fecundity, and fertility were determined, and we elaborated the fertility life table at different temperatures. We also determined the thermal requirements, and the number of annual generations in olive producing areas were estimated. All immature stages of P. forficifera were affected negatively by the temperature at 10 and 35 °C, whereas 25 and 30 °C provided the shortest egg-to-adult periods. However, larval viability was affected at 30 °C (48.7%). Highest fecundity (325.5 eggs) was found for P. forficifera females kept at 25 °C. Additionally, the highest net reproduction rates (Ro) and intrinsic population growth rates (Rm) were verified at 25 and 30 °C. Lower thermal threshold (Tb) and thermal constant (K) for the egg-to-adult period were 10.7 °C and 549.45 degree-d, respectively. Based on the thermal requirements, P. forficifera can produce 4.0 to 6.3 generations per yr in the olive producing regions of Brazil and Uruguay. Results of the present study are important for understanding the occurrence of P. forficifera under field conditions and to aid strategic management designs. [ABSTRACT FROM AUTHOR]

The present work objectify to determine the proportion between males and females in the population of A. chloropterus allocated in CETAS (Wild Animal Screening Center) in Bahia, Brazil. Twelve individuals allocated to CETAS in Porto Seguro were studied; these comprised all the green-winged macaws allocated to CETAS in Bahia in the study period. Molecular sexing took place, using blood from a cut nail as biological material. The processing of the samples occurred through DNA extraction, PCR using the primers 2550F/2718R and electrophoresis in 2% agarose gel. Females were identified by two bands of approximately 650 and 450 bp and males by a single band close to 650 bp. In addition, during sample collection, direct behavioral observation of specific events was carried out, in order to identify the formation of pairs among the studied animals. Of the 12 individuals analyzed, 7 (58,3%) were females and 5 (41,7%) males. This resulted in a sexual ratio close to 1:1; similar to that expected in populations of free-living parrots. From the behavioral assessment, it was possible to infer the formation of at least 2 heterosexual social pairs. This is the first work to report the sex ratio in a population of A. chloropterus. [ABSTRACT FROM AUTHOR]

Anthropogenic activities have decimated the Atlantic Forest domain (AF) and increased the pressure on freshwater biota, such as Trichoptera, which is the most affected order by the current insect decline. Adult mobility is crucial for the colonisation of new environments unconnected by water sources. In this article, we describe the assemblage of caddisflies in a preserved AF fragment related to their functional feeding group and provide empirical data on the patterns of horizontal and vertical flight. Adults were collected using white sheet and light attraction traps, placed at different distances and heights from a stream in Pernambuco, Brazil. A total of 2934 specimens of 15 species from five families were collected, mostly collector-filterers. Horizontal flight was limited, with 80% of the abundance concentrated up to 20 m. Vertical stratification was also concentrated at lower heights. A female-biased proportion was observed at higher strata. The richness and abundance of species decreased with increasing distances and heights from the stream. Overall, Chimarra sp. and Macrostemum scharfi were the dominant species. Trichoptera is a key taxon used as a biological indicator of water quality, and here, knowledge on the diversity and flight patterns of adults is expanded. At the risk of intensive pollution of rivers in Atlantic forests, data on the adult dispersal can be incorporated in the assessment of endangerment status and in conservation strategies., (© 2024. Sociedade Entomológica do Brasil.)

Intersex has been reported regularly in wild populations of gonochoristic fish. The authors investigated the possible feminization of seahorses in a population of Hippocampus reidi in Brazil, as well as report a case of a brood pouch reduction after reproductive stimuli. The female seahorses of this population showed two kinds of morphological anomalies. The proportion of the animals affected in the study population was consistent and was uncorrelated with the sex ratio. The study indicates the changes in the sexual profile of the individual. [ABSTRACT FROM AUTHOR]

This study aimed to determine biological and distributional aspects of deep‐sea giant isopods Bathynomus giganteus and Bathynomus miyarei to assess their extinction risk.Bathynomus giganteus (663 specimens) and B. miyarei (649 specimens) were collected during five research cruises involving 265 h of sampling effort during 32 fishing operations of circular pots, baited traps, ranging from 400 and 1,000 m deep, between 26 and 29°S adjacent to the Brazilian coast.A trend towards larger, sexually mature animals in shallower regions was observed for both species, and depth was the most important environmental variable influencing the animals' distribution.Bathynomus giganteus were collected between 600 m and 1,000 m depth, while the highest densities of B. miyarei were at shallower depths, between 400 and 600 m.The sex ratio was equal for both B. giganteus and B. miyarei for different seasons, latitudes and bathymetries.The sexual maturity of B. giganteus was estimated at 340–345 mm total length for males and between 280–290 mm for females. Bathynomus miyarei males' sexual maturity was estimated in the 225–230 mm size class.Bathynomus giganteus showed reproductive activity throughout the year.The longevity of B. giganteus was estimated at 6 years for males and 7.7 years for females. The longevity of B. miyarei was estimated at 9 years for males and 6 years for females.Extinction risk assessment for B. giganteus, which has a greater latitudinal and bathymetric distribution, was evaluated as Least Concern. However, B. miyarei was evaluated in the Data Deficient category. [ABSTRACT FROM AUTHOR]

Costal upwelling and other oceanographic features exert important effects on neritic and benthic communities, causing variations in the reproduction and survival of organisms. Here, we assessed the population structure, sex ratio, recruitment, and reproduction of the caridean shrimp Nematopalaemon schmitti near the Cabo Frio upwelling area in southeastern Brazil. In total, 759 individuals were captured. N. schmitti exhibited a unimodal size–frequency distribution pattern with larger females, and the binomial test indicated a significantly female‐biased sex ratio. The time‐series analysis showed synchrony between ovigerous females and juveniles that revealed continuous reproduction and the possible existence of recruitment areas. Our findings indicate that reproductive parameters are influenced by the environmental factors of the region studied here. We advocate that the influence of the sedimentary composition of the soft bottom and upwelling system of Cabo Frio is the predominant factors influencing the reproductive parameters in N. schmitti. [ABSTRACT FROM AUTHOR]

The purpose of this study is to determine the parameters of the reproductive biology of seven commercial species at the Ramsar Site of the Baixada Maranhense to support fisheries management measures. The collections were carried out between 2012 and 2016. The reproductive period, sex ratio, weightlength relationship and first sexual maturity were evaluated for seven species of commercial importance. The sex ratio showed that females are predominant for all species, except for Plagioscion squamossissimus. The weight-length relationship indicated a greater investment in weight for Cichla monoculus and Hassar affinis, and a greater investment in length for Hoplias malabaricus, Plagioscion squamosissimus, Prochilodus lacustris, Pygocentrus nattereri, and Schizodon dissimilis. The reproductive activity of the species was predominant in the rainy season, but C. monoculus, H. malabaricus and P. lacustris showed the ability to reproduce in both seasons. As management measures for the region, it is suggested a change in the closed fishing season established by IBAMA, from December 1 to April 30, to ensure the protection of all commercial species in this study. [ABSTRACT FROM AUTHOR]

Parthenogenesis and sex-ratio bias may lead to erroneous assumptions concerning the natural history of some arachnids. To help address this issue, this study provides new data on the sex ratio and geographic distribution of sexual populations of the scorpion Tityus stigmurus (Thorell, 1876). Ultraviolet light lanterns were used to detect specimens during nocturnal searches performed in both urban and non-urban environments scattered thorough northeastern Brazil. Males of T. stigmurus were reported for 10 new localities, and although we did not find males in urban environments, nonurban populations presented near symmetrical sex ratios. Such results suggest that reproductive strategies in this species may be modulated by environmental conditions. Also, the general tendency of less biased sex ratios in non-urban environments reported here is in accordance with previous studies that indicated the occurrence of geographical parthenogenesis in this species. Thereby, we propose that sexual populations of T. stigmurus are less rare than previously reported. [ABSTRACT FROM AUTHOR]

The reproductive strategy of the non‐native predator cichlid Cichla kelberi was determined to explain its success after more than 60 years of being introduced into an isolated reservoir in southeastern Brazil. This was one of the first‐known translocations of the genus Cichla out of its natural range. Macro‐ and microscopy characteristics of the gonadal development stages and the maturation phases, along with the reproductive features (size at first maturation size, gonado‐somatic index and sex ratio), were described. It was hypothesized that the stable conditions of the reservoir, with low connectivity, weakly defined spatial gradient and slight seasonal changes in environmental variables, favour the equilibrium strategy that enables predators to have high offspring survivorship because of great parental investment in individual progeny. Sex ratio was well balanced, with males and females reaching first maturity between 30.0 and 28.6 cm total length (LT), respectively. The stages of oocyte (primary and secondary growth, vitellogenic and atresia) and spermatocyte (spermatogonia, spermatocytes, spermatids and spermatozoa) development were identified. Five phases of gonadal development (immature, developing, spawning capable, regressing and regenerating) were described for both sexes. A long reproductive season was found, with spawning peaks in August/September and, to a lesser extent, in April/May. Parental care and spawns in parcels (batch spawns) corroborated the raised equilibrium strategy that was effective in this isolated reservoir. This species developed reproductive mechanisms that fit to different environmental conditions, with multiple spawning being associated with lentic environments and asynchronous development of oocytes, which are released over long periods. The reproductive plasticity in reservoirs may be one of the main factors inherent to the successful of colonization and establishment of the peacock bass in the environments in which they were introduced. [ABSTRACT FROM AUTHOR]

In dioecious species, females usually have higher sex-related costs than males. Consequently, trade-offs involving survival, growth, and reproduction are expected to differ between sexes. Here, we investigate several aspects of sex-related costs to test whether they are higher for females than males of a widely distributed, locally abundant, dioecious tropical forest tree species. For this, every adult of Mollinedia schottiana (Spreng.) Perkins (Monimiaceae) had its stem diameter at soil height (DSH) and spatial location measured in two 1-ha plots located at the Atlantic Rainforest, SE Brazil. Flowering phenology was also recorded over 12 months. At a second population census, the surviving individuals from the first census had their DSH remeasured. In comparison to males, females did not flower less frequently, less intensely, or in a lower proportion over 12 months. They also did not grow less between censuses, have larger DSH, or show spatial segregation from males. However, sex ratio was male biased, which, together with floral biology, is likely a strategy of M. schottiana to pollination by thrips. This study shows that dioecious species do not necessarily have differential sex-related costs as expected by the higher investment in reproductive structures by females. Sex ratios, which are often interpreted as a result of sex-related costs, can be driven by the reproductive biology of plant species. [ABSTRACT FROM AUTHOR]

Brazil's Bolsa Família Programme (BFP) aims to combat poverty and social inequalities through monetary transfers to families. A much-discussed indirect effect of the programme was its correlation to the fertility of the beneficiary families. In this paper, we use a cohort fertility approach with parity progression ratios that differs from existing literature, which mainly used period fertility measures, to better understand the relationship between fertility and the BFP. This study analyses the relationship between the BFP and the reproduction of Brazilian women. We use data from the 2010 Brazilian micro-censuses, the only census after the start of the BFP in 2004, to reconstruct the childbirth history of women with incomplete reproductive cycles (women aged 25 to 29), and estimate parity progression ratios (PPRs) and cohort fertility rates (CFR). In addition, we estimate propensity score matching (PSM) models comparing fertility outcomes of beneficiaries and non-beneficiaries of the programme. Our results show distinct differences in CFRs and PPRs. On average, BFP beneficiaries had more children than women not covered by the programme. This finding remained consistent even after controlling for educational gradients and other covariates. Our empirical findings show that women opt for a "rational" strategy, where they tend to have children in more rapid succession up until three children. These findings contradict the recent literature that has not found any correlation between BFP and fertility. The results also suggest that cohort analyses may fill certain gaps left by previous studies of period fertility. This paper is one of a few that have analysed the relationship between a conditional income transfer programme and cohort measures in Brazil. [ABSTRACT FROM AUTHOR]

Habitat fragmentation due to human activities is one of the principal threats to all primates and is particularly so for arboreal platyrrhines. Its impact has been extreme in the Brazilian Atlantic forest, where most primate populations have been severely reduced in numbers and their distributions restricted, resulting in low probabilities of long-term persistence. One of the most severely affected species is the northern muriqui (Brachyteles hypoxanthus), which today has fewer than 1,000 individuals distributed over only a dozen populations and is considered to be Critically Endangered. Most of these populations are isolated and smaller than 50 individuals, including the population inhabiting the Sossego Forest in Simonésia, Minas Gerais. With fewer than 30 individuals associating in one social group, the Sossego muriqui population is doomed to extinction unless emergency management measures are implemented to protect it. We monitored the demography of the Sossego muriquis to evaluate the impacts of the introduction of a reproductive-aged female that was translocated into this population in December 2006. Data were collected on all individuals, identifiable from their natural markings, during 3 to 12 monthly surveys conducted each year from July 2012 to June 2020. They revealed that the population grew from 32 individuals in July 2012 to a peak of 38 in September 2015, but then declined to a low of 22 individuals in September 2017, coinciding with a yellow fever outbreak in the region. As of June 2020, there were 24 individuals present. Four of the surviving individuals were the translocated female and three of her five offspring. One of her daughters was confirmed to have emigrated to another forest fragment and a second daughter has not been seen since March 2019 and is suspected to have emigrated. During the eight years of monitoring, we recorded 17 births (11 females and six males) and 25 disappearances involving 17 females, including the female confirmed to have dispersed, and eight males. Our results emphasize the risks of demographic stochasticity in small, isolated populations. The confirmed emigration of one dispersal-aged female that failed to locate a group to join, and the absence of any immigrants, call attention to the demographic implications of translocation as a potential conservation tool for small, isolated populations of species such as the northern muriqui in which female dispersal and male philopatry are typical. [ABSTRACT FROM AUTHOR]

This study investigates the nesting habits of Epicharis picta in a nest aggregation located in a fragment of the Atlantic forest in Southeastern Brazil. Ten emergence-traps were set up in this nest aggregation to standardize data collection of phenology, natural enemies, and sex ratio. Epicharis picta nests were in an area of 160 m² with a density of 41 nests/m². Nest and cell architecture are described. Epicharis picta is a protandrous, univoltine species with its emergence in this study occurring between 28 January and 15 April. We provide direct evidence of parasitism on E. picta by Rhathymus friesei, Tetraonyx sexguttata and T. aff. lycoides. The predator Apiomerus lanipes was found to prey Epicharis for the first time. We suggest the use of emergence-traps as tools to support studies of ground-nesting bees. In addition, we compile, update, and discuss data on the nesting biology of all Epicharis subgenera. [ABSTRACT FROM AUTHOR]

Temperature-dependent sex determination occurs in many species of turtles. Because substrates differ in their heat retention capacities, a relatively small change in ambient temperature can exert great influence on sex ratios of hatchlings from clutches deposited in different substrates even within the same geographical area. Since Podocnemis unifilis is one of the Amazonian turtle species (Podocnemididae) with high behavioural plasticity in the use of nesting sites, we tested the influence of soil types on hatchling sex ratios in the Piagaçu Purus Sustainable Development Reserve along the lower Purus River, Brazil. During the 2013 and 2014 nesting seasons, we evaluated 26 nests on a sand bank (n = 14) and clay banks (n = 12). Approximately half of the hatchlings that emerged from each nest were sexed via gonad histological analysis (n = 341). We found a higher incidence of females in nests from the sandy substrate and more males in nests from the clayey substrate (= 40.466, df = 1, P < 0.0001). Ratios of 1 male to 2.28 females were recorded from sand bank nests, and 1.9 males to 1 female from clay banks. Overall, however, the hatchling sex ratio approximated to 1:1. Due to the gradual increase in global temperatures, it has been suggested for species with Temperature Sex Determination (TSD) that some turtle populations become increasingly female-dominated. However, it is likely that the use of different nesting substrates may help to mitigate the effects of global warming on hatchling sex ratio, especially in species with greater behavioural plasticity, such as P. unifilis. [ABSTRACT FROM AUTHOR]

The present study analyzes the population structure of Palaemon pandaliformis, based on sex ratio, the frequency distribution in defined size classes and the reproductive biology of samples captured in seasonal collections (winter 2011 to autumn 2012) with sieves under marginal vegetation. A total of 1,043 specimens were obtained, 222 juveniles, 465 males and 356 females, being that of this total of females, 58.42% were in the ovigerous condition. The average size of the carapace for both sexes varied between 4 and 6 mm (p> 0.05) only the ovigerous females had higher averages (p <0.0001). The sex ratio differed with 1:0.76 for males (p = 0.0001), although juvenile individuals and females were present in all sampled periods, except ovigerous females in autumn. Highest abundances were observed during the winter and spring period (p = 0.0001), decreasing in the periods with higher water temperature and salinity (summer and autumn). Was observed a continuous recruitment due to the presence of juveniles in all seasons, with greater abundance in winter and spring. Thus, based on the presence of ovigerous females in almost all seasons and juveniles in all, the reproduction for P. pandaliformis can be defined as seasonal-continuous with peak in winter period. [ABSTRACT FROM AUTHOR]

Introduction: Understanding the various aspects of the reproductive biology of fish is a key step towards applying effective strategies for sustainable management of fishery resources. Objective: We aimed to evaluate the sex ratio, reproductive period and lengths at first maturity for 30 fish species caught in the Verde River, upper Paraná River Basin, Brazil. Methods: Fish were sampled monthly from November 2010 to March 2011 and from October 2011 to February 2012, and sampled quarterly from May to August in 2011 and 2012; totaling 14 samples. Fish were measured and weighed in the laboratory. In addition, gender and gonadal developmental stage were identified macroscopically. Subsequently, the sex ratio was determined and significant differences were tested using the chi-square ((f) method. The reproductive period was determined with the use of gonadal developmental stages and the gonadosomatic index. Lastly, length at first maturity was estimated only for the species that presented individuals with sufficient immature and mature gonads to adjust the model. Results: Of the captured individuals, 51.5 % were male, and 48.5 % were female. Fifteen species showed significant differences in their sex ratios. The reproductive period for most species occurred from October to February, with reproductive peaks in November, December and January. The length at first maturity was estimated for only five species, including Salminus brasiliensis, a keystone species. Conclusions: The sex ratios revealed that for many species, there is a predominance of males over females, which was not expected for this parameter. The reproductive period follows the same pattern observed in Neotropical fish. However, it is noteworthy that some species are starting their reproduction in August. Lastly, estimating length at first maturity for most Neotropical fish remains a challenge, which may lead to difficulties in the use of protective measures to maintain fisheries and conserve fish species. [ABSTRACT FROM AUTHOR]

Recent molecular analyses characterized the freshwater crab Trichodactylus fluviatilis as a species complex. Considering this new scenario, studies about the population features are fundamental to understanding the biology of species belongs to this complex. We investigated the population from southeastern Brazil identify as Trichodactylus cf. fluviatilis, testing the hypotheses that sex ratio differs from the expected 1:1, and that the species shows sexual dimorphism in size, weaponry and body weight. The reproductive period and handedness were also investigated. Population features were determined based on the size-frequency distribution, gonadal development and sex ratio. Sexual dimorphism was analysed comparing the average size and the allometric coefficient. Handedness was verified according to the proportion of right and left chelipeds. Sex ratio skewed towards males and the reproduction was continuous. The sexual dimorphism in T. cf. fluviatilis was found in structures related to weaponry and reproduction. In weaponry, sexual dimorphism was demonstrated by robust chelipeds and high allometric values in males. In females, a high allometric was recorded to the abdomen, structure directly related to reproduction. The right-handedness was observed to the species. All these results contribute to a better understanding of the species' life history. [ABSTRACT FROM AUTHOR]

The study of population and reproductive traits provides information about the ecological structure of natural populations. This study aimed to characterize dynamics and reproductive traits of Hyalella palmeirensis from a natural pond from southern Brazil. The amphipods were sampled monthly (August 2012 to July 2013) by a person with the aid of a hand net for 20 minutes. Ovigerous females and pre-copulatory pairs were individualized in the field. A total of 12,325 individuals were sampled, being 1,421 males, 6,983 females (including 215 ovigerous females) and 3,921 juveniles. Paired and unpaired males were significantly greater in size than females. There was a positive correlation between body size (CL) of paired males and females. Males and females showed bimodal distribution. Total sex ratio favored females, and these were more frequent in almost all months. Ovigerous females and precopulatory pairs were found throughout the year, but with high frequency in winter and autumn, respectively, characterizing a seasonal reproduction. Juveniles were sampled throughout the year, with greater intensity in the spring. The mean fecundity was 19.6 ± 4.34 eggs. No reduction in the number of eggs was observed during embryonic development. The results observed in H. palmeirensis demonstrate that this species has a population and reproductive dynamics very similar to other species of Hyalella already analyzed in southern Brazil. Moreover, it can be seen that although the H. palmeirensis occurs in an environment with anthropic influence (soy cultivation,) the population is managing to remain in the area, with reproduction and recruitment in most months of year. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Estudos Urbanos e Regionais is the property of Associacao Nacional de Pos-Graduacao e Pesquisa em Planejamento Urbano e Regional and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Rocky outcrops in the intertidal zones of estuaries often contain a highly diverse microbenthic community which includes the hermit crab, Clibanarius symmetricus, an abundant species on the equatorial Amazon coast. However, the ecology of this anomuran is poorly understood. Given this, the present study investigated the spatiotemporal distribution and structure of the C. symmetricus populations that inhabit the rocky outcrops of the Marapanim estuary in northern Brazil. Samples were collected monthly over a yearly cycle covering both the dry and rainy seasons in the upper and lower midlittoral zones during low tide. The distribution and abundance of C. symmetricus were affected directly by environmental factors such as temperature, seasonality, the intertidal zone, and salinity. The population presented sexual dimorphism, with males being larger than females, a male-biased sex ratio (1.5:1), a nonnormal and unimodal distribution, continuous reproduction, and sexual maturation at a cephalothoracic shield length of 3.6 mm. Despite the unique characteristics of the Amazon coast and the study estuary, the spatiotemporal distribution and structure of the C. symmetricus population were similar to those recorded at higher latitudes. [ABSTRACT FROM AUTHOR]

• Phaedrotoma scabriventris and Zaeucoila unicarinata can coexist. • Simultaneous exposure to the parasitoids increases the mortality of Liriomyza sativae. • Simultaneous exposure increases P. scabriventris parasitism on L. sativae. • Exposure after Z. unicarinata increases parasitism by P. scabriventris. Liriomyza sativae Blanchard is a key pest of melon (Cucumis melo L.) in Brazil and a target of biological control using parasitoids. Even though they share similar niches and competitive interactions can occur, Phaedrotoma scabriventris Nixon and Zaeucoila unicarinata Ashmead are potential candidates for controlling L. sativae in melon. Here, we investigated interactions between P. scabriventris (Ps) and Z. unicarinata (Zu) under laboratory conditions. We evaluated: (1) puparia to verify both parasitism and the interactions between parasitoid immature stages; and (2) emerged adults to verify host mortality due to parasitism, host stinging, host feeding, and parasitoid sex ratios. We observed in the dissected puparia that P. scabriventris predominated in all three forms of interaction evaluated. In addition, predation and physical combats were observed between immature stages of both parasitoids. When we consider the emerged adults, both species showed a similar parasitism rate in isolation (P. scabriventris , 19.40 ± 3.57 % and Z. unicarinata , 17.60 ± 4.54 %). The sequential interaction (Zu → Ps) significantly decreased the parasitism by Z. unicarinata (4.92 ± 0.14 %) compared to its parasitism rate in isolation. The greatest total parasitism rate was observed when both species simultaneously (Ps + Zu) parasitised the larvae (51.28 ± 3.08 %). Phaedrotoma scabriventris and Z. unicarinata caused the greatest non-reproductive larvae mortality under the isolated exposure forms (35.90 ± 2.55 % and 37.00 ± 4.60 %, respectively). The sex ratio decreased significantly only in P. scabriventris (22.62 % of females) in the sequential interaction (Ps → Zu). Our results indicate that both P. scabriventris and Z. unicarinata should be used in combination in the control of L. sativae in melon. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Field Ornithology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A field study of the sex ratio, length-weight ratio, body size at first gonadal maturation, and the breeding season of the redtailed catfish, Phractocephalus hemioliopterus, was carried out in the region of the middle Xingu River in the eastern Amazon basin. The fish were sampled quarterly from September 2012 to January 2014 using gillnets and long lines. The sex ratio was balanced, and while males and females were similar in standard length, the females were heavier than the males, on average. The males presented negative allometric growth, and the females, isometric growth. The estimated size at first maturity was 77.8 cm. The variation in the gonadosomatic index and the greater frequencies of mature specimens indicated a reproductive peak at the beginning of the high-water (flood) period. As P. hemioliopterus is an important commercial fish, our findings will contribute to the future development of effective conservation and management strategies, such as minimum catch size and a close season that is appropriate for the region. These data will also provide important insights for the evaluation of potential impacts on the biology of this fish resulting from the construction of Belo Monte dam. [ABSTRACT FROM AUTHOR]

The marine crab Plagusia depressa, despite its broad geographic range, is not well known. Here, we attempt to fill this gap by studying several aspects of its biology. We sampled P. depressa in the reefs of Coruripe, Brazil and investigated the sex ratio, body size, maturity, the allometric growth of the gonopod in males and of the abdomen in females, the reproductive effort, the breeding season and the influence of environmental variables. We found that 1) the sex ratio, overall, does not deviate from 1:1; 2) females (33.71±10.62 mm) are larger than males (30.45±9.94 mm; t1,764: -4.40, p<0.001); 3) males (23.42±0.24 mm) mature at smaller sizes than females (26.78±0.19 mm); 4) the growth of the gonopod is positive allometric in juveniles (slope = 1.66±0.04), but negative allometric in adolescents (0.93±0.02) and adults (slope = 0.86±0.03). In females, the abdomen undergoes a positive allometry in juveniles (slope = 1.74±0.04) and adolescents (slope = 1.97±0.09), but an isometric growth in adults (slope = 0.99±0.04); 5) the breeding period is continuous and not influenced by rainfall, water temperature and salinity; 6) egg mass strongly increases with body mass (slope = 1.56, R2=0.84, p<0.001). [ABSTRACT FROM AUTHOR]

Background: In French Guiana, a French overseas territory in South America, 6 to 10 thousands undocumented persons work illegally in gold mining sites in the Amazonian forest. Precarious life conditions lead to poor health but few data exist on the health status of illegal gold miners in French Guiana. The objective of this article was to describe the sociodemographic and health status of this vulnerable population.Method: A prospective cross-sectional survey was conducted in 2015 on gold mine supply sites at the border between French Guiana and Suriname. Health status was assessed through medical examination, past medical history, haemoglobin concentration, and HIV and malaria testing. A questionnaire was used to collect data about the migration itinerary and life conditions on mining sites.Results: Among the 421 adults included in the study, 93.8% (395/421) were Brazilian, mainly from Maranhão (55.7%, 220/395), the poorest Brazilian state. The sex ratio was 2.4. Overall, 48% of persons never went to school or beyond the primary level. The median time spent in gold mining was quite long (10 years), with a high turn-over. One third of the surveyed population (37.1%, 156/421) had high blood pressure, and only two had a medical follow-up. Most persons had experienced malaria (89.3%, 376/421). They declared frequent arboviroses and digestive disorders. Active leishmaniasis was observed in 8.3% of gold miners. Among women, 28.5% were anemic. Concerning HIV, 36.6% (154/421) of persons, mainly men, never got tested before and 6 were tested positive, which represented an HIV prevalence of 1.43% (95%CI =0.29-2.5).Conclusion: These findings support the hypothesis that mining in remote areas is linked to several specific illnesses. Theoretically, gold miners would be presumed to start their economical migration to French Guiana as a healthy group. However, their strenuous working and living conditions there lead to poor health caused by infectious and non infectious diseases. This description of their health status is precious for health policy planners in French Guiana given the importance of controlling communicable disease, and the severity and range of specific illnesses acquired by this neglected population.Trial Registration: Clinical trial registration PRS N° NCT02903706 . Retrospectively registered 09/13/2016. [ABSTRACT FROM AUTHOR]

Static life tables were used to establish demographic parameters such as size-class structure, abundance trends, sex ratio, net reproductive rate, generation time, and per capita rate of population growth for a population of the amphipod Parahyale hawaiensis (Dana, 1853) (Hyalidae) from the intertidal belt of a red alga Bryocladia trysigera (J. Agardh) F. Schmitz in southeastern Brazil. Collections were taken monthly from December 2012 to November 2013. There were two reproductive peaks, a higher one, May to July, and a second throughout the warmer months, October to January. The continuous reproduction results in the overlapping of generations. A sex ratio biased in favor of females was recorded in all sampling dates, a common pattern in epifaunal species. The estimated net reproductive rate was 1.45 ± 1.01 young per female, the generation time 3.51 ± 1.31 months, and the population growth rate 0.06 ± 0.17 per capita per month. The logistic growth model indicates that an initial population of 10 individuals would reach the carrying capacity for the species in a natural environment in 35 to 40 generations time, a period equivalent to 130 to 150 months. As a result of extinction model application, no possibility of extinction was predicted for the local population. The estimated parameters can be used as endpoints in ecotoxicological tests. [ABSTRACT FROM AUTHOR]

This paper provides the first description of the nesting biology of Ancistrocerus flavomarginatus (Brèthes) (Hymenoptera, Vespidae, Eumeninae), the only species of the genus found in Brazil. Our trap-nest experiments were conducted in two Mixed Ombrophilous Forest fragments and two adjacent matrices in Guarapuava (Paraná state, Brazil) from August 2017 to July 2018. In each area, we set 192 trap nests divided into six groups of 32 units, totalling 768 trap nests. We obtained a total of 47 nests of A. flavomarginatus, the vast majority of them (43, 91.5%) founded in the forest fragments. Most nests were built in wooden traps with a bore diameter of either 5 or 7 mm (19 nests in each type, 80.8%). Nests comprised 1-12 subcylindrical brood cells arranged linearly and separated from one another by transverse partitions of soil mastic. Larvae consumed 6-10 lepidopteran caterpillars before spinning the cocoon. Ancistrocerus flavomarginatus produced up to 6 annual generations (multivoltinism) and its immature forms were parasitized by chrysidid and ichneumonid wasps. The calculated sex ratio (1.78:1) was statistically biased towards males, but since they (21.3 ± 2.0 mg) were significantly lighter than females (50.9 ± 4.0 mg), the resulting investment ratio (1.34:1) was female biased. Males emerged from more external cells and developed significantly faster (27.2 ± 0.46 days) than females (30.1 ± 0.66 days), hence a case of protandry. We demonstrated that A. flavomarginatus is largely dependent on the Atlantic Rainforest and thus that deforestation poses a critical threat to this important species., (© 2022. Sociedade Entomológica do Brasil.)

The oil spill that reached Brazilian Coast in 2019 was one of the most extensive disasters and its effects on distinct species are still under investigation. This study evaluated the effects of the oil spill on the crab Pachygrapsus transversus in four reef areas in Northeast of Brazil that are also under different levels of chronic anthropogenic impacts. Changes in population aspects were investigated including maturity, sex ratio, and relative growth considering periods before and after the oil spill. An acute decrease in the number of females captured in areas most affected by oil spill was evident and may be associated with the closure of burrows used for protection. Crabs from the most touristic area presented a decrease in the medium size of carapace and maturation compared to crabs from other less visited areas, which highlights the importance of studying the effects of impacts on marine fauna. • Population aspects of Pachygrapsus transversus from four reefs were investigated. • Each reef environment present varied chronic impacts. • Study period covered before and after the 2019 oil spill. • The arrival of the oil impacted the sex ratio of Pachygrapsus transversus. • Intense trampling on reefs has an influence on the size and maturation of the species. [ABSTRACT FROM AUTHOR]

The population biology and size at sexual maturity of Uca (Uca) maracoani were studied for the first time in a semi-arid tropical estuary of northeastern Brazil. A catch-per-unit-effort (CPUE) technique was used to sample the crabs, on the surface and inside burrows, for 60-min sampling periods by one person on a monthly basis during spring low tide periods from June 2013 to June 2014 in an estuary area of Baixa Grande Beach. A total of 406 crabs were obtained, of which 317 were males, 87 non-ovigerous females, and two ovigerous females. Males were larger than non-ovigerous females. The U. (U.) maracoani population presented unimodal size frequency distribution, which may reflect a continuous recruitment, with no disruption of classes and constant mortality rates, indicating a stable population. The overall sex ratio (3.5 males: 1 female) differed significantly from the expected 1:1 proportion. The major cheliped was on the right side in 45.1% of the males, as reported for other fiddler crabs populations. A total of 294 males and 89 females were used in the allometric study. The specimens were measured at carapace width (CW), the major propodus length (MPL) of males, and abdomen width (AW) of females. In males, the relationship between CW and MPL was 22.3 mm CW, which is considered the functional value at maturity. In females, the size at sexual maturity was 19.3 mm CW based on the relationship between CW and AW. The CPUE method is discussed as one of the reasons of the high sex ratio skewed towards males. This is the first account regarding population structure of U. (U.) maracoani in semi-arid tropical areas. [ABSTRACT FROM AUTHOR]

The broad-snouted caiman (Caiman latirostris) is a South American crocodilian with a wide geographical distribution. Water bodies originally occupied by the species have suffered extreme anthropogenic pressure; however, the broad-snouted caiman has a high adaptive capacity to colonize man-made habitats such as decanting pounds and artificial reservoirs for agriculture or livestock. In this context, the present study aimed at identifying the population structure of the broad-snouted caiman in a silvicultural landscape in southeastern Brazil. Fifty-two caimans of various classes were captured with baited traps and steel cable snares at night. The estimated population size was 51 individuals excluding class I individuals. The population density was estimated to be 2.6 individuals/ha with a linear density of 11.3 individuals/km. The intermediate values of linear density estimates herein are similar to other areas, suggesting that silvicultural landscapes can be relevant for broad-snouted caiman conservation. Therefore, the role of silvicultural landscapes in crocodilian conservation should be taken into consideration for environmental certification processes related to forestry in the Neotropics. [ABSTRACT FROM AUTHOR]

Hyalella longistila is a freshwater amphipod found in streams in southeastern Brazil. We examined temporal variations in the population dynamics of this species by analyzing its abundance, size frequency distribution, proportion of mating pairs and brooding females, sex ratio and recruitment, as well as the possible influence of environmental variables on such parameters. Samples were made in a stream in the state of Minas Gerais from March 2012 to February 2013. The size frequency distribution was polymodal for most of the months, with more than one maximum for both juveniles and adults. The maximum size attained by females (brooding and non-brooding) was higher than in males and the mean size of males (paired and unpaired) was higher when comparing with paired and unpaired females, respectively. Hyalella longistila seems to reproduce continuously but more intensively twice a year, in the middle of winter and end of spring. Recruitment occurred during several months (April, May, October, November, and December 2012), which could have affected the observed polymodal distribution. It is likely that this continuous breeding activity was possible due to the abundant macrophyte stand where the population inhabits, which could have provided constant shelter and feeding for individuals, but this aspect still needs to be investigated further. Moreover, a positive effect of dissolved oxygen on the frequency of brooding females, as well as of temperature on the abundance were recorded. Our results can help future researches in the conservation of aquatic ecosystems as a whole, more specifically for the preservation of Hyalella longistila and its use as a test organism. [ABSTRACT FROM AUTHOR]