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1.
Environ Pollut ; 336: 122447, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37648055

RESUMO

In Suriname, mercury (Hg) use has recently increased because of gold mining, which has put fish-reliant communities (e.g., Indigenous and Tribal) at risk of enhanced Hg exposure through the riverine fish these communities consume. To quantify how the magnitude of these risks change according to location and time, we measured total mercury (HgT) in fish at sites downstream and upstream of an artisanal and small-scale gold mining (ASGM) operation in 2004-2005 and in 2017-2018. We tested whether fish HgT burdens over dynamic ranges were increased. Surprisingly, our findings did not support broadly increased fish Hg burden over time or that proximity to ASGM was diagnostic to fish HgT-burden. Subsequently, we elected to test the HgT stable isotope ratios on a set of freshly collected 2020 fish to determine whether differences in Hg source and delivery pathways might cofound results. We found that remote unmined sites were more susceptible to gaseous elemental Hg deposition pathways, leading to enhanced risk of contamination, whereas ASGM proximate sites were not. These results highlight that elemental mercury releases from ASGM practices may have significant impact on fish-reliant communities that are far removed from ASGM point source contamination.


Assuntos
Mercúrio , Animais , Mercúrio/análise , Exposição Ambiental/análise , Suriname , América do Sul , Ouro , Peixes/metabolismo , Monitoramento Ambiental
2.
PLoS One ; 16(6): e0250390, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34077471

RESUMO

The impacts of ecotourism on biodiversity are poorly understood and the outcome of this type of research is often contradictory. On the one hand ecotourism could impact the occurrence, survival or behavior of species, on the other hand ecotourism is often mentioned as providing a "human shield" by deterring negative practices like gold mining, logging and hunting. Brownsberg Nature Park is easily the most visited protected area of Suriname, with a high number of ecotourists visiting from abroad. A four-year study on the impact of ecotourism on medium-large terrestrial mammals was carried out between 2013 and 2016 using 16 camera trap stations. The area has a clear gradient of tourism pressure, with the pressure decreasing further away from the lodging facilities. Evidently, the impacts of human presence on the mammal communities were more significant in the busiest areas. Most species avoided areas with many hikers or switched to a more nocturnal activity pattern. In these areas the impact was not reflected in species numbers, however it was causing a significant decrease in the diversity of mammals. On the other hand, vehicles had little impact on species avoidance or diversity, but did increase nocturnality, even more than hikers. A few species seemed to be "attracted" by hikers and/or traffic. Giant armadillos (Priodontes maximus) and spotted pacas (Cuniculus paca) used the pools in the road created by traffic. Ocelots (Leopardus pardalis), margays (Leopardus wiedii) and red-rumped agoutis (Dasyprocta leporina) seemed to favor human disturbance probably because of predator release. Some of the most impacted species were the jaguar (Panthera onca), puma (Puma concolor) and lowland tapir (Tapirus terrestris), all three species with significant contribution to ecosystem balance. Management measures should focus on lowering the number of hikers in popular places and limiting the number of vehicles in recreational areas.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Mamíferos/fisiologia , Turismo , Animais , Densidade Demográfica , Suriname
3.
J Expo Sci Environ Epidemiol ; 31(1): 117-125, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32461550

RESUMO

Previous research has found that women and children living in rural, interior communities in Suriname have high concentrations of mercury in hair. Freshwater fish from these areas also have high concentrations of mercury. Artisanal and small-scale gold mining operations in parts of the country use elemental mercury to extract gold from soils and sediments. Total mercury and methylmercury concentrations have been determined in hair and blood from pregnant women across the country. Pregnant women from interior communities have significantly higher concentrations of both total and methylmercury in hair (median total mercury in hair 3.64 µg/g) compared with pregnant women from two urban coastal cities, Paramaribo (0.63 µg/g) and Nickerie (0.74 µg/g). Total and methylmercury concentrations in blood and hair are highly correlated (r = 0.986, r = 0.974) with methylmercury making up 86% of the total in blood and 97% of the total in hair. Most women in the interior regions rely heavily on local fish as part of their regular diet, and many live outsides of areas with active ASGM operations. This study demonstrates that diet and fish consumption largely govern mercury exposures in pregnant women in Suriname.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Animais , Criança , Cidades , Exposição Ambiental/análise , Feminino , Peixes , Contaminação de Alimentos , Ouro , Humanos , Mercúrio/análise , Gravidez , Gestantes , Saúde Pública , Suriname
4.
Zootaxa ; 4820(1): zootaxa.4820.1.7, 2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-33056085

RESUMO

Anomaloglossus is a species-rich genus of frogs endemic to the Guiana Shield that still harbours several unnamed species. According to a recent integrative taxonomic survey, the A. stepheni species group includes five valid nominal species and at least four putatively unnamed species, two in Brazil and two in Suriname. In this paper, we describe the two species from Suriname based on adult and tadpole morphology as well as their calls and natural history. Both have exotrophic tadpoles transported by the male to small water bodies. These two new species differ from each other and from other congeners in body size, colouration pattern, call characteristics and breeding sites. Both have narrow distributions and should be considered Endangered according to IUCN criteria.


Assuntos
Anuros , Animais , Larva , Masculino , Suriname
5.
BMJ Open ; 10(9): e034702, 2020 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-32928846

RESUMO

PURPOSE: The Caribbean Consortium for Research in Environmental and Occupational Health prospective environmental epidemiologic cohort study addresses the impact of chemical and non-chemical environmental exposures on mother/child dyads in Suriname. The study determines associations between levels of environmental elements and toxicants in pregnant women, and birth outcomes and neurodevelopment in their children. PARTICIPANTS: Pregnant women (N=1143) were enrolled from December 2016 to July 2019 from three regions of Suriname: Paramaribo (N=738), Nickerie (N=204) and the tropical rainforest interior (N=201). Infants (N=992) were enrolled at birth. Follow-up will take place until children are 48 months old. FINDINGS TO DATE: Biospecimens and questionnaire data on physiological and psychosocial health in pregnant women have been analysed. 39.1% had hair mercury (Hg) levels exceeding values considered safe by international standards. Median hair Hg concentrations in women from Paramaribo (N=522) were 0.64 µg/g hair (IQRs 0.36-1.09; range 0.00-7.12), from Nickerie (N=176) 0.73 µg/g (IQR 0.45-1.05; range 0.00-5.79) and the interior (N=178) 3.48 µg/g (IQR 1.92-7.39; range 0.38-18.20). 96.1% of women ate fish, respective consumption of the three most consumed carnivorous species, Hoplias aimara, Serrasalmus rhombeus and Cichla ocellaris, known to have high Hg levels, was 44.4%, 19.3% and 26.3%, respectively, and was greater among the interior subcohort. 89% frequently consumed the vegetable tannia, samples of which showed presence of worldwide banned pesticides. 24.9% of pregnant women had Edinburgh Depression Scale scores indicative of probable depression. FUTURE PLANS: Fish consumption advisories are in development, especially relevant to interior women for whom fish consumption is likely to be the primary source of Hg exposure. Effects of potentially beneficial neuroprotective factors in fish that may counter neurotoxic effects of Hg are being examined. A pesticide literacy assessment in pregnant women is in progress. Neurodevelopmental assessments and telomere length measurements of the children to evaluate long-term effects of prenatal exposures to toxicant mixtures are ongoing.


Assuntos
Serviços de Saúde Materna , Mercúrio , Saúde Ocupacional , Animais , Região do Caribe , Saúde da Criança , Pré-Escolar , Exposição Ambiental/efeitos adversos , Etnicidade , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mercúrio/toxicidade , Gravidez , Estudos Prospectivos , Suriname
6.
Zootaxa ; 4576(3): zootaxa.4576.3.2, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-31715747

RESUMO

Anomaloglossus is a species-rich genus of frogs endemic to the Guiana Shield that still harbors several unnamed species. Within the A. stepheni species group (which includes four valid nominal species), A. baeobatrachus has an uncertain taxonomic status, notably because the holotype was an unvouchered specimen depicted in a popular journal. Another member of this group, A. leopardus, was only superficially described, lacking information on the sex of specimens in the type series and on advertisement call. Therefore, these two taxa need clarifications in order to allow the description of the extant undescribed species. In this paper, we redescribe A. baeobatrachus based on newly collected material from the species type locality and provide information about its reproductive ecology. We also provide an amended definition of A. leopardus using newly collected material from its type locality. These two species form a clade along with a third species from the Eastern Guiana Shield, which is also described herein. The reproductive biology of A. baeobatrachus and A. stepheni is very similar. Both species have endotrophic and nidicolous tadpoles, despite being distantly related, suggesting independent evolution of this breeding mode. The new species and A. leopardus, on the other hand, have exotrophic tadpoles.


Assuntos
Anuros , Reprodução , Animais , Guiana , Larva
7.
Artigo em Inglês | MEDLINE | ID: mdl-29772808

RESUMO

Natural sources of mercury, historical gold mining, and contemporary artisanal and small-scale gold mining (ASGM) activities have led to mercury contamination in Suriname. Our primary objective was to evaluate mercury levels in hair of women and children from interior villages in Suriname where mercury levels in fish are elevated. We also estimated blood levels of mercury using an established mathematical conversion to facilitate comparison with other biomonitoring programs in the United States. Estimated levels of mercury in the blood of participants from Suriname were significantly higher than those in women from a heavy marine fish-consuming population in southeast Louisiana and estimates of the US national average. This includes women from Surinamese villages well upstream of ASGM activities. Since residents in these areas rely heavily on local fish, this is likely the source of their exposure to mercury. The levels in hair are similar to those seen in women from longitudinal studies finding neurological impairments in children exposed pre- and postnatally. Additional biomonitoring and neurodevelopmental assessments are warranted in these areas, as well as other areas of the Suriname. Mercury levels in hair (Suriname) and blood (southeast LA USA) were determined using cold vapor atomic absorption spectroscopy (CVAAS).


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Mercúrio/análise , Adolescente , Adulto , Criança , Pré-Escolar , Poluentes Ambientais/sangue , Feminino , Cabelo/química , Humanos , Lactente , Masculino , Mercúrio/sangue , Pessoa de Meia-Idade , Mineração , Saúde da População Rural , Alimentos Marinhos , Suriname
8.
Zootaxa ; 4379(1): 1-23, 2018 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-29689971

RESUMO

A large portion of the amphibian species occurring in Amazonia remains undescribed. A recent study on species delineation in Anomaloglossus, a genus endemic to the Guiana Shield, demonstrated the existence of two undescribed species previously identified as A. degranvillei, which we describe herein. In addition to divergence at the molecular level, these two new taxa are also distinguished by subtle morphological characters and substantial differences in the advertisement calls (note length, dominant frequency, note structure). One species occurs in the hilly lowlands of north-eastern French Guiana and is mainly distinguished from its closest relatives by a small body size (15.9-18.8 mm in males) and by vocalisations characterized by the emission of short notes of 0.09 s on average. The other species is only known from the Itoupé Massif in southern French Guiana and is mainly distinguished from its closest relatives by a moderate body size (19.4-20.4 mm in males) and by vocalisations characterized by the emission of long notes of 0.23 s on average. We also provide amended definitions for two previously described species in the A. degranvillei species group: A. degranvillei, which is endemic to a few massifs in central French Guiana, and A. surinamensis, which is distributed throughout Suriname and French Guiana. The new species described here and A. degranvillei have very narrow ranges within French Guiana and seem to have rapidly declined during the last decade. Therefore, we suggest A. degranvillei and A. dewynteri to be considered as "Critically Endangered" and A. blanci as "Vulnerable" according to the IUCN standards.


Assuntos
Anuros , Animais , Tamanho Corporal , Guiana Francesa , Guiana , Masculino , Suriname
9.
Mol Phylogenet Evol ; 112: 158-173, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28438699

RESUMO

Lack of resolution on species boundaries and distribution can hamper inferences in many fields of biology, notably biogeography and conservation biology. This is particularly true in megadiverse and under-surveyed regions such as Amazonia, where species richness remains vastly underestimated. Integrative approaches using a combination of phenotypic and molecular evidence have proved extremely successful in reducing knowledge gaps in species boundaries, especially in animal groups displaying high levels of cryptic diversity like amphibians. Here we combine molecular data (mitochondrial 16S rRNA and nuclear TYR, POMC, and RAG1) from 522 specimens of Anomaloglossus, a frog genus endemic to the Guiana Shield, including 16 of the 26 nominal species, with morphometrics, bioacoustics, tadpole development mode, and habitat use to evaluate species delineation in two lowlands species groups. Molecular data reveal the existence of 18 major mtDNA lineages among which only six correspond to described species. Combined with other lines of evidence, we confirm the existence of at least 12 Anomaloglossus species in the Guiana Shield lowlands. Anomaloglossus appears to be the only amphibian genus to have largely diversified within the eastern part of the Guiana Shield. Our results also reveal strikingly different phenotypic evolution among lineages. Within the A. degranvillei group, one subclade displays acoustic and morphological conservatism, while the second subclade displays less molecular divergence but clear phenotypic divergence. In the A. stepheni species group, a complex evolutionary diversification in tadpole development is observed, notably with two closely related lineages each displaying exotrophic and endotrophic tadpoles.


Assuntos
Anuros/classificação , Anuros/genética , Variação Genética , Acústica , Animais , Teorema de Bayes , Brasil , DNA Mitocondrial/genética , DNA Ribossômico/genética , Ecossistema , Larva/crescimento & desenvolvimento , Funções Verossimilhança , Filogenia , Análise de Componente Principal , Reprodução , Especificidade da Espécie
10.
Zootaxa ; 4052(1): 39-64, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26624776

RESUMO

Many Amazonian frog species that are considered widely distributed may actually represent polyspecific complexes.. A minute tree frog from the Guiana Shield originally assigned to the allegedly widely distributed Dendropsophus brevifrons proved to be a yet undescribed species within the D. parviceps group. We herein describe this new species and present a phylogeny for the D. parviceps group. The new species is diagnosed from other Dendropsophus of the parviceps group by its small body size (19.6-21.7 mm in males, 22.1-24.5 mm in females), thighs dorsally dark grey with cream blotches without bright yellow patch, absence of dorsolateral and canthal stripe, and an advertisement call comprising trills (length 0.30-0.35 s) composed of notes emitted at a rate of 131-144 notes/s, generally followed by click series of 2-3 notes. Its tadpole is also singular by having fused lateral marginal papillae and absence of both labial teeth and submarginal papillae. Genetic distances (p-distance) are >5.3% on the 12S and >9.3% on the 16S from D. brevifrons, its closest relative. This species occurs from the Brazilian state of Amapá, across French Guiana and Suriname to central Guyana and is likely to also occur in adjacent Brazilian states and eastern Venezuela. This species is not rare but is difficult to collect because of its arboreal habits and seasonal activity peaks.


Assuntos
Anuros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Anuros/anatomia & histologia , Anuros/genética , Anuros/fisiologia , Tamanho Corporal , Ecossistema , Feminino , Guiana , Masculino , Tamanho do Órgão , Filogenia , Vocalização Animal
11.
Ambio ; 41(8): 873-82, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22669686

RESUMO

Mercury levels in sediment and predatory fish were measured for 53 localities in Suriname. The average mercury level in bottom sediment surpassed the Canadian standard for sediment in most localities, except the coastal plains. Of the predatory fish, 41 % had a mercury level above the European Union standard for human consumption of 0.5 µg g(-1). Highest mercury levels were found in fish from the Brokopondo Reservoir and from the Upper Coppename River. High levels of mercury in fish in pristine areas are explained by atmospheric transportation of mercury with the northeastern trade winds followed by wet deposition. Contrary to gold mining areas, where mercury is bound to drifting sediments, in "pristine" areas the mercury is freely available for bio-accumulation and uptake. Impacts on piscivorous reptiles, birds, and mammals are unknown, but likely to be negative.


Assuntos
Ecossistema , Ouro , Mercúrio/análise , Mineração , Poluentes Químicos da Água/análise , Animais , Suriname
12.
Neotrop. ichthyol ; 5(3): 351-368, July-Sept. 2007. mapas, tab, ilus
Artigo em Inglês | LILACS | ID: lil-465946

RESUMO

We investigated long-term changes in the fish fauna of Brokopondo Reservoir, Suriname, the first large reservoir (1560 km²) that was created in tropical rainforest. Before closure of the dam in 1964, the fish fauna of Suriname River had 172 species, high diversity and high evenness. The riverine fauna was dominated by small-sized species, but no single species was dominant in numbers. Large catfishes were dominant in biomass. Species were evenly distributed over riverine habitats: rapids, tributaries and main channel. Four years after closure of the dam, only 62 fish species were collected from Brokopondo Reservoir, but the composition of the fish fauna was still changing. The reservoir fauna in 1978 was very similar to the reservoir fauna in 2005, indicating that a stable equilibrium had been reached 14 years after closure of the dam. The reservoir fauna had 41 species, low diversity and low evenness. Most species of Suriname River and its tributaries with strict habitat requirements did not survive in Brokopondo Reservoir. Fish community structure was different among four habitats of Brokopondo Reservoir. The open-water habitat (10 species) was dominated by the piscivores Serrasalmus rhombeus, Acestrorhynchus microlepis and Cichla ocellaris and their prey Bryconops melanurus and two Hemiodus species. B. melanurus fed on zooplankton, Culicinae pupae and terrestrial invertebrates. Hemiodus fed on fine flocculent detritus, demonstrating that the detritus-based food chain was still important in late stages of reservoir development. Serrasalmus rhombeus also fed on peccaries that drowned when swimming across the large reservoir in rough weather. The shore community (27 species) was dominated by seven cichlids, but early stages and juveniles of the open-water species S. rhombeus and B. melanurus also occurred in the shore habitat. Fish biomass in the shore habitat was 66.5±59.9 kg ha-1. The cichlid Geophagus surinamensis and the characid...


Foram pesquisadas as modificações a longo prazo na ictiofauna do reservatório de Brokopondo, o primeiro de grande porte (1560 km²) construído em floresta tropical úmida. Antes do fechamento da barragem em 1964, a ictiofauna do rio Suriname possuía 172 espécies, com diversidade e equitabilidade altas. A fauna do rio era dominada por espécies de pequeno porte, mas nenhuma delas dominava em número de indivíduos. Em termos de biomassa, os grandes bagres eram dominantes. As espécies estavam homogeneamente distribuídas nos diferentes hábitats: corredeiras, afluentes e canal principal. Quatro anos depois do fechamento da barragem, somente 62 espécies de peixes foram coletadas no reservatório de Brokopondo, mas a composição da ictiofauna ainda estava mudando. Em 1978, a ictiofauna do reservatório era semelhante à de 2005, indicando que um equilíbrio estável foi atingindo 14 anos depois do fechamento da barragem. A ictiofauna do reservatório tinha 41 espécies, diversidade e equitabilitade baixas. A maioria das espécies do rio Suriname que tinham exigências estreitas de hábitat não sobreviveram no reservatório. A estrutura das comunidades de peixes foi diferente nos quatro hábitats do reservatório de Brokopondo. O hábitat das águas abertas (10 espécies) foi dominado pelos piscívoros Serrasalmus rhombeus, Acestrorhynchus microlepis e Cichla ocellaris e suas presas Bryconops melanurus e duas espécies de Hemiodus. Bryconops alimentou se de zooplâncton, pupas de Culicidae e invertebrados terrestres. Hemiodus alimentou se de detritos floculentos, demostrando que a cadeia alimentar baseada em detritos ainda era importante em estßgios avançados de desenvolvimento dos reservatórios. Serrasalmus rhombeus também come queixadas que se afogam quando tentam atravessar nadando o grande reservatório em condições de mau tempo. A comunidade das margens (27 espécies) foi dominada por sete Cichlidae, embora estágios iniciais e juvenis das espécies de águas abertas...


Assuntos
Animais , Fauna Aquática , Biodiversidade , Barragens , Peixes , Florestas
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