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The benthic biodiversity of the abyssal Labrador Sea was investigated using Agassiz trawl and in situ imagery. A megafaunal scaphopod associated with an epizoic anemone was recovered from soft sediments. Morphological and molecular investigations revealed the scaphopod to be an undescribed species in the dentaliid genus Fissidentalium P. Fischer, 1885. The new scaphopod species is characterised by a large size for the genus, is moderately curved, with numerous narrow, longitudinal ribs (60 ribs at 11 mm diameter ventral aperture), a dentaliid radula, and is described herein as Fissidentalium aurae sp. nov. The new species shows a close genetic relationship to congeners of Fissidentalium and separates from the sister genera Dentalium Linnaeus, 1758 and Antalis H. Adams & A. Adams, 1854. Genetic COI barcoding of the epizoic anemone suggests the species is a member of the family Actinostolidae Carlgren, 1932. The discovered association of a burrowing scaphopod with an epifaunal anemone at abyssal depth is a new record for the region and is indicative of how little is known about symbioses in the deep sea. [ABSTRACT FROM AUTHOR]

Environmental certificates in aquaculture are becoming important market tools throughout the world. However, there are important regional and national differences, and Brazil, due to the low number of certified companies, deserves specific research. A preliminary analysis of the Brazilian aquaculture market shows a large market with strong growth and more than 25 cultivated species, but where 80% of the turnover is focused on tilapia, tambaqui, and white shrimp, primarily targeting the domestic market with very few exceptions to the external market. These particular conditions seem to explain the low number of certified aquaculture companies, even when compared to other countries in the region with similar or smaller aquaculture industries. This study interviewed managers from 80 companies in the Brazilian aquaculture production chain, including all certified companies. The results seem to be in line with previous studies conducted in different parts of the world. The main benefits associated with aquaculture certifications are access to new markets and production improvement, while the main barriers to certification are high costs, lack of awareness, bureaucracy, or lack of government support. Certified Brazilian aquaculture companies share similar characteristics among themselves but differ from most companies in Brazil; they are all large-scale firms, mainly related to tilapia production and oriented towards the international market. The low number of certified companies seems to be linked to the large demand for aquatic products in Brazil that even Brazilian aquaculture firms cannot satisfy. [ABSTRACT FROM AUTHOR]

Hesperidin (Hsd), a bioactive phytomedicine, experienced an antidiabetic activity versus both Type 1 and Type 2 Diabetes mellitus. However, its intrinsic poor solubility and bioavailability is a key challenging obstacle reflecting its oral delivery. From such perspective, the purpose of the current study was to prepare and evaluate Hsd-loaded sulfobutylether-β-cyclodextrin/chitosan nanoparticles (Hsd/CD/CS NPs) for improving the hypoglycemic activity of the orally administered Hsd. Hsd was first complexed with sulfobutylether-β-cyclodextrin (SBE-β-CD) and the complex (CX) was found to be formed with percent complexation efficiency and percent process efficiency of 50.53 ± 1.46 and 84.52 ± 3.16%, respectively. Also, solid state characterization of the complex ensured the inclusion of Hsd inside the cavity of SBE-β-CD. Then, Hsd/CD/CS NPs were prepared using the ionic gelation technique. The prepared NPs were fully characterized to select the most promising one (F1) with a homogenous particle size of 455.7 ± 9.04 nm, a positive zeta potential of + 32.28 ± 1.12 mV, and an entrapment efficiency of 77.46 ± 0.39%. The optimal formula (F1) was subjected to further investigation of in vitro release, ex vivo intestinal permeation, stability, cytotoxicity, and in vivo hypoglycemic activity. The results of the release and permeation studies of F1 manifested a modulated pattern between Hsd and CX. The preferential stability of F1 was observed at 4 ± 1 °C. Also, the biocompatibility of F1 with oral epithelial cell line (OEC) was retained up to a concentration of 100 µg/mL. After oral administration of F1, a noteworthy synergistic hypoglycemic effect was recorded with decreased blood glucose level until the end of the experiment. In conclusion, Hsd/CD/CS NPs could be regarded as a hopeful oral delivery system of Hsd with enhanced antidiabetic activity. [ABSTRACT FROM AUTHOR]

Located 1140 km from the South American coastline in the South Atlantic Ocean and with an age of 4 million years, Trindade Island is the most recent volcanic component of Brazilian territory. Its original native vegetation has been severely damaged by human influence, in particular through the introduction of exotic grazing animals such as goats. However, since the complete eradication of goats and other feral animals in the late 1990s, the island's vegetation has been recovering, and even some endemic species that had been considered extinct have been rediscovered. In this study, we set out to characterize the contemporary cryptic diversity in soils of the recovering native forest of Trindade Island using metabarcoding by high throughput sequencing (HTS). The sequence diversity obtained was dominated by microorganisms, including three domains (Bacteria, Archaea, and Eukarya) and five kingdoms (Fungi, Metazoa, Protozoa, Chromista, and Viridiplantae). Bacteria were represented by 20 phyla and 116 taxa, with Archaea by only one taxon. Fungi were represented by seven phyla and 250 taxa, Viridiplantae by five phyla and six taxa, Protozoa by five phyla and six taxa, Metazoa by three phyla and four taxa and Chromista by two phyla and two taxa. Even after the considerable anthropogenic impacts and devastation of the island's natural forest, our sequence data reveal the presence of a rich and complex diversity of microorganisms, invertebrates, and plants and provide important baseline biodiversity information that will contribute to ecological restoration efforts on the island. [ABSTRACT FROM AUTHOR]

Coastal zones support the most productive marine ecosystems, yet they are increasingly threatened by anthropogenic stressors such as dredging. In this study, we investigated how seasonal variation and dredging activities conducted during the construction of a harbor and submarine base (Sepetiba Bay, RJ, Brazil) affected the phytoplankton and zooplankton assemblages. The observed temporal variability at five different sites over 10 years revealed that dredging exceeds the expected influence of dry and rainy seasons on plankton abundance and diversity. In general, the abundance of both groups increased during dredging due to the resuspension of nutrients and benthic organisms. This increase was particularly evident in the dinoflagellate Scrippsiellaa cuminata, the diatoms Thalassiosira rotula and Nitzschia longissima, and the herbivorous zooplankton Acartia clausii and Pseudevadne tergestina. Moreover, season and dredging activities synergistically influenced plankton assemblages, resulting in larger seasonal variations during dredging activities. After the end of the harbor construction, plankton abundance decreased and remained low until the end of the monitoring, which may indicate persistent changes in the biodiversity and ecosystem functioning of impacted areas. [ABSTRACT FROM AUTHOR]

Trindade Island, Brazil, is a small, remote volcanic island located 1140 km off the coast of southeastern Brazil. The green turtle (Chelonia mydas) nesting aggregation on Trindade is genetically distinct, the largest in the southwest Atlantic, and represents the southern limit of green turtle nesting in the Atlantic. Projeto TAMAR (a Brazilian conservation program) has monitored the nesting aggregation discontinuously since 1982. In 2009, a standardized protocol was established for the two beaches (Andradas and Tartarugas) with the highest nest abundance. Data from December 2009 through April 2017 (except 2013) were used in this study. Annual numbers of tracks left by females that emerged onto the beach vary between 558 and 3317 tracks for Andradas and between 760 and 3559 tracks for Tartarugas. Mean nesting probabilities (probability that an emerging female deposits eggs) for all years were 0.22 (95% HDI (highest posterior density interval) = 0.14–0.30) for Andradas and 0.45 (95% HDI = 0.37–0.53) for Tartarugas. Nesting probabilities varied among and within years and had a negative relationship with daily track counts. During our study, annual estimates of nests were stable on both Andradas (range 38–2001) and Tartarugas (range 248–2769). Nest abundance estimates between 1991 and 2008 from an earlier study indicated a stable population, extending the duration of apparent stability to 26 years with the caveat that the studies used different estimation methods. This stability is in contrast with the increasing trends for most green turtle nesting aggregations in the Atlantic. [ABSTRACT FROM AUTHOR]

Individual variability within a population and the eventual repeatability across time and space may provide stability in a population facing environmental changes, by affecting individuals differently. Thus, the variability and repeatability of behaviours, habitats used, niches and migratory pathways could play an important role. Trindade petrels (Pterodroma arminjoniana) are threatened seabirds that breed year round on Trindade Island in the South Atlantic Ocean, migrate to North Atlantic Ocean in the non-breeding periods, and use wide oceanic areas. This study investigated the timing, at-sea distribution, and trophic niche throughout the annual cycle of the austral fall/winter breeding group of Trindade petrel and examined consistency in distribution and trophic niche used by the Trindade petrel at the individual level, in different breeding seasons, using geolocator tracking and stable isotope analysis. Results demonstrated that petrels breed annually, maintaining their breeding schedules. Petrels share a common, vast oligotrophic oceanic area during both breeding and non-breeding periods inside the South Atlantic and North Atlantic Subtropical Gyres, respectively. Two migratory patterns were identified and used repeatedly by individuals. Although petrels overlapped at-sea distributions in consecutive breeding seasons, consistency in parameters tested was not found. Breeding in two schedules along the year, in addition to the use of different migratory pathways and flexibility in their isotopic niche can be an advantage for Trindade petrel population to cope with environmental changes. Causes and consequences of variable niche and pathways used, and the existence of consistency and variability among birds breeding later on the year remain poorly-known. [ABSTRACT FROM AUTHOR]

The objective of this research is to investigate the pollution levels of tin (Sn), arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), mercury (Hg), and zinc (Zn) of soil/sediment taken in Coles Bay Area (CBA), Svalbard, and Great Bay Area (GBA), China, in an attempt to evaluate the pollution potential related to recent development in the areas. A total of 150 soil/sediment samples were collected in each location. Heavy metal concentrations were detectable levels at all sites and the values of Cd of all soil/sediment samples were higher than Dutch Target and Intervention Values. Heavy metal concentration in soil/sediment was further analyzed by principal component analysis (PCA). It was revealed that three components were found in two studying sites and contributed 60.2% and 75.9% of variations to reflect soil/sediment quality in CBA and GBA, respectively. Based on the results of KMO (0.52) and Bartlett's test (p < 0.000), there are 32.1%, 15.6%, and 11.1% and 39.45%, 19.01%, and 17.52% of the variance in the first, second, and third component explained that the metal concentration of Pb, Cd, and Sn was highly correlated with the soil/sediment quality in CBA and GBA, respectively. Among these three heavy metals, Cd concentration was the common dominant factor to affect soil/sediment quality in these two study sites. It is recommended that investigation of the sources of pollution (either point or non-point source) during CBA or GBA development and management together with consideration of abiotic (soil)-biotic (organisms) interactions should be taken into account when choosing suitable remediation strategies in the future. [ABSTRACT FROM AUTHOR]

Seabirds breeding in tropical environments experience high energetic demands, when foraging in an oligotrophic environment. The globally threatened Trindade petrel Pterodroma arminjoniana has its largest colony in Trindade Island (20°30′S-29°19′W) inside the oligotrophic South Atlantic Subtropical Gyre. Diet sampling methods, geolocator tracking and stable isotope analysis were used to describe its diet, compare foraging trips and distributions, and assess temporal variations in the trophic niche throughout the breeding period. Diet consisted mainly of squid and fish. The high species diversity and wide range of prey sizes consumed suggests the use of multiple foraging techniques. Stable isotope mixing models confirm that Trindade petrels rely mainly on squid throughout the breeding period. Its broad isotopic niche seems to reflect both a diverse diet and foraging range, since birds can reach up to 3335 km from the colony. Isotopic niche showed limited variation even in an 8-year interval, apparently due to oceanographic stability, although changes in the isotopic niche have demonstrated an adjustment to different conditions in different seasons. Petrels change foraging areas and prey during the breeding period: pre-incubating birds use more productive areas west of Trindade Island and obtain low trophic position prey; incubating petrels perform longer trips southward to consume prey of high trophic position; and chick-rearing petrels use areas around the island. These results demonstrate that to deal with high demand breeding in a colony surrounded by oligotrophic waters, Trindade petrels need to explore wide foraging areas and utilize a diverse diet, besides adjusting trophic niche according to breeding stage. [ABSTRACT FROM AUTHOR]

Among the diverse patterns of energy allocation to the offspring of gastropods, the presence of egg capsules to protect embryos is common. Females of the edible snail Zidona dufresnei attach egg capsules to hard substrates in shallow Argentine Patagonian waters (40°45′S, 64°56′W) during spring-summer. Embryonic development takes about 30 days at 22°C. In this study, three likely capsule predator species and the marks left by each on egg capsule walls were identified in laboratory experiments in February 2010. Abundances of predators and egg capsules with evidence of predation were assessed in the field in the summers of 2010 and 2011. Under laboratory conditions ( N = 10 replicates per treatment and control), the predation rate by the chiton Chaetopleura isabellei was the highest (up to 90%), followed by the gastropod Tegula patagonica and the crab Neohelice granulata (~20% each). Nearly 60% of 41 capsules found in the field showed signs of predation. According to the marks identified in the laboratory, C. isabellei was responsible for 79% of this predation, and T. patagonica for the rest. Predation appears to be important during the encapsulated early life and could be an agent for selecting for resistant capsule walls and a relatively shorter development time. [ABSTRACT FROM AUTHOR]

The edible volutid snail Adelomelon ancilla occurs on the Argentine coast and may have the capacity to serve as source of support for local fisheries. However, knowledge of its reproduction is lacking. Over 3 years (from September 2000 to July 2004) we studied the oviposition at Golfo Nuevo, Patagonia by diving. Monthly collections were performed to examine gonadal stages histologically during 2002–2003. Gamete development stages corresponded with the expected period for oviposition occurring from July to November, a time of increasing day length. Oviposition also took place in March when water temperature attained a maximum of 18°C. Following the spawning period, remaining gametes were resorpted in both sexes. Males contained sperm throughout the year, parasperm and eusperm forms were found within the same acinus. Oogonia/oocytes ranged from 20 to 240 μm in diameter during oogenesis. Females commenced laying egg capsules from a shell length of 114 mm. Reproduction is compared with other fishable volutid snails from the Argentine shelf, and suggests the need to apply certain fishing restrictions if the resource begins to be utilized commercially. The imposex condition was found in snails from some shipping areas. The frequency of this condition declined with distance from the port. [ABSTRACT FROM AUTHOR]

Stable isotopes of growing feathers and blood both represent assimilated diet, and both tissues are used to study the diet and foraging distribution of marine and terrestrial birds. Although most studies have assumed that both tissues represent a difference of one trophic level to diet, the enrichment factors of blood and feathers may differ, especially where endogenous reserves are used as precursors during feather synthesis. In this study, we compare carbon and nitrogen stable isotopes of blood and simultaneously growing feathers of five species of Procellariiformes, representing five genera, different geographical regions and different life stages (chicks and adults). In all species, feathers were enriched in 15N and 13C compared with blood. Isotopic values of carbon and nitrogen were correlated in different tissues growing simultaneously for most species analyzed, suggesting that mathematical corrections could be used to compare different tissues. Our results imply that more care needs to be taken when comparing stable isotope signatures across studies assuming different tissues are equivalent indicators of trophic ecology. [ABSTRACT FROM AUTHOR]

Growth, age and somatic production of the benthic predator Odontocymbiola magellanica were studied in Golfo Nuevo (42°S 65°W), on the South American Atlantic shelf. Stable oxygen isotope ratios confirmed semiannual formation of internal and external shell growth marks. Mean shell length (SL) of females was 115 and 112 mm for males, while population modal shell-free wet mass (SFWM) was 62.8 g. A Gompertz growth function (SL∞ = 200 mm, K = 0.197, t 0 = 5.486) fitted 113 pairs of size-at-age data (12 shells) best. O. magellanica is a long-lived species, reaching up to 20 years of age. The maximum individual somatic production of 29.3 g SFWM per year is attained at 145 mm SL, which corresponds to about 12 years of age. The life span of this volutid seems to be twice compared with other large gastropods. O. magellanica is a valuable and exploitable resource regarding its large size and somatic production, but on the other hand, its slow growth, late maturity and direct development makes it extremely vulnerable to overexploitation. [ABSTRACT FROM AUTHOR]

Growth, age and somatic production of the benthic predator Adelomelon brasiliana were studied at the southern limit of its distribution on the South American Atlantic shelf. Stable oxygen isotope ratios confirmed annual formation of internal shell growth marks. Modal shell length of the population was 140 mm, while modal shell-free wet mass was 255 g. A logistics growth function (SL∞=186.28 mm, K=0.185, t0=4.601) fitted 131 pairs of size-at-age data (25 shells) best. A. brasiliana is a very long-lived species, reaching up to 20 years of age. The maximum individual somatic production of 46 g shell-free wet mass year−1 is attained at 145 mm shell length, which corresponds to about 12 years of age. [ABSTRACT FROM AUTHOR]

The reproductive season of the Adelomelon brasiliana population of Mar del Plata extends from September to April (austral spring and summer), showing synchronisation with water temperature. Adult gonad state is related to shell-free wet mass. Oocytes reach 200 μm in diameter before spawning. In autumn, a resting phase begins, when no new oocytes develop and the non-spawned ones undergo reabsorption. Gonadic development begins during the early winter, when new previtellogenic oocytes can be observed through histology. The long reproductive season would increase the ability of the species to recover from harvesting. [ABSTRACT FROM AUTHOR]

Compares the frequency of occurrence of pelagic versus benthic development of prosorobranch gastropods along two latitudinal gradients of South America based on Thorson's rule on marine invertebrates. Background on Thorson's rule; Impact of the physical history of the coast and water on the development of gastropods; Factors contributing to the differences in developmental modes of gastropods.