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1.
An Acad Bras Cienc ; 94(suppl 1): e20210706, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35648995

RESUMEN

Global climate change is expected to increasingly affect climate-sensitive sectors of society, such as the economy and environment, with significant impacts on water, energy, agriculture and fisheries. This is the case in South America, whose economy is highly dependent on the agricultural sector. Here, we analyzed the sensitivity of South American climate to positive extremes of Antarctic sea ice (ASI) extent and volume at continental and regional scales. Sensitivity ensemble experiments were conducted with the GFDL-CM2.1 model and compared with the ERA-Interim reanalysis dataset. The results have shown significant impacts on the seasonal regime of precipitation, air temperature and humidity in South America, such as a gradual establishment of the South Atlantic Convergence Zone, the formation of the Upper Tropospheric Cyclonic Vortex, the strengthening of Bolivian High and the presence of a low level cyclonic circulation anomaly over the South Atlantic Subtropical High region which contributed, for instance, to increased precipitation over the Southeastern Brazil. A northward shift of the Intertropical Convergence Zone was initially also a response pattern to the increased ASI. Moreover, the greatest variance of the climatic signal generated from the disturbances applied on the high southern latitudes has occurred in the interseasonal timescale (110-120 days), especially over the Brazilian Amazon and the Southeastern Brazil regions.


Asunto(s)
Cambio Climático , Cubierta de Hielo , Regiones Antárticas , Brasil , Temperatura
2.
Sci Rep ; 11(1): 24100, 2021 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-34916552

RESUMEN

An approximate 1:1 sex ratio of American lobsters can be skewed due to environmental factors or fisheries management. Substantial skewness can impact mating behaviour and lower reproduction which could have far-reaching ecological and economic consequences. The aim was to investigate the sex ratio patterns of lobsters in two lobster fishing areas (LFAs) in southwestern Nova Scotia, Canada and identify factors associated with skewed sex ratios. This study analyzed biological data from more than 270,000 lobsters sampled over ten years (2010-2019) by the Fishermen and Scientists Research Society. A mixed effect logistic regression model evaluated the effect of spatial, temporal and environmental factors as well as size on the sex ratio of lobsters. There were significant temporal patterns in sex ratios that differed by LFA. After the effects of sampling month, year and LFA were accounted for, lower bottom temperature and deeper water depth were associated with a higher prevalence of females, especially in larger lobsters. We present the first long term analyses of sex ratio patterns in H. americanus in Atlantic Canada's most commercially important region for this species and provide evidence that these patterns are influenced by environmental factors and fisheries. In view of future climate change scenarios, monitoring the population dynamics of this iconic fishery species is crucial to ensure sustainable fisheries and healthy lobster stocks.


Asunto(s)
Ecosistema , Explotaciones Pesqueras , Nephropidae/fisiología , Reproducción/fisiología , Razón de Masculinidad , Conducta Sexual Animal/fisiología , Animales , Cambio Climático , Femenino , Modelos Logísticos , Masculino , Nueva Escocia , Agua de Mar , Mariscos , Temperatura , Factores de Tiempo
3.
J Aquat Anim Health ; 33(4): 199-219, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34687087

RESUMEN

Regulatory costs on aquaculture farms have been shown to be of a magnitude that warrants additional analysis. The drivers of farm-level costs of fish health inspections were identified in this study from national survey data on U.S. salmonid farms. The greatest costs identified were related primarily to state fish health requirements for inspection and testing to certify that fish are free of specific pathogens prior to approval of necessary permits to sell and/or transport animals. Fish health inspection costs included laboratory testing, farm personnel time, veterinary fees, and shipping samples to laboratories, with laboratory testing and the value of farm personnel time being the most expensive components. Principal cost drivers were the number of tests and whether required sampling was farmwide or for each lot as identified by the collector. Farmers who primarily sold into recreational markets had greater fish health costs than farmers who primarily sold food fish because of the greater numbers of species and size-/age-classes of salmonids on their farms. Regulatory requirements to test all species and size-/age-classes on farms increased inspection costs by increasing the total number of tests, the total value of fish sacrificed, and shipping costs. Consequently, for farms with more than one species or more than one size-/age-class, annual farm-level testing was less costly than annual lot-based testing. Increased numbers of tests in a given year, although reported by only a few respondents, can increase costs dramatically and turn profitable farms unprofitable, even food fish farms. Smaller salmonid farms experienced disproportionately greater inspection cost burdens than did larger farms. The fish health inspection scenario of only one annual inspection of only the most susceptible species and size-/age-class showed a cost burden that did not generate economic distress, even on smaller salmonid farms. Other scenarios modeled (based on survey data) that included lot-based surveys of multiple species and size-/age-classes resulted in substantially greater fish health inspection costs that led to unprofitability for various farm sizes and business types. Study results suggest that implementing Comprehensive Aquaculture Health Program Standards might allow for risk- and pathogen-based reductions in the total number of inspections and fish sampled while maintaining equivalent or greater health status compared to current methods. American Fisheries Society-Fish Health Section Blue Book inspection methods are interpreted and applied inconsistently across states and generally yield lot- rather than farm-level health attestations because the history of testing results, risk assessment, and biosecurity practices are not typically taken into account. The cost effects of alternative fish health sampling and testing requirements should be considered in decisions and policy on fish health regulation.


Asunto(s)
Explotaciones Pesqueras , Salmonidae , Animales , Acuicultura , Granjas , Estados Unidos
5.
Prev Vet Med ; 145: 110-120, 2017 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-28903867

RESUMEN

Bacterial kidney disease (BKD), caused by Renibacterium salmoninarum, threatens salmonid populations throughout the Northern hemisphere. Many fishery regulatory authorities require ongoing disease monitoring in hatcheries and spawning runs prior to gamete collection to prevent BKD outbreaks and spread. According to diagnostic protocols of the American Fisheries Society-Fish Health Section, monitoring for R. salmoninarum generally consists of lethal sampling of visceral organs from fish. However, non-lethal sampling would be preferable, especially for valuable broodstock or endangered species. In this study, non-lethal sampling methods were evaluated for their ability to detect R. salmoninarum in Chinook salmon (Oncorhynchus tshawytscha) that were experimentally infected via two different routes (e.g., intraperitoneal injection and waterborne immersion) to mimic acute and chronic disease courses. Non-lethal (e.g., blood, mucus, and a urine/feces mixture) and lethal (e.g., kidney and spleen homogenate) samples were collected from challenged and mock-challenged Chinook salmon and the presence of R. salmoninarum was assessed by culture on modified kidney disease medium, nested polymerase chain reaction (nPCR), and semi-quantitative enzyme-linked immunosorbent assay (ELISA). Sensitivity, specificity, and accuracy of lethal and non-lethal samples in detecting R. salmoninarum were calculated using receiver operating characteristic (ROC) analyses. For ROC analyses, true disease status was evaluated under two different assumptions: 1) that lethal samples represented the true disease status and 2) that all experimentally challenged fish were truly infected. We found that sensitivity and specificity of non-lethal samples depended upon time of sampling after experimental infection, sample type, and R. salmoninarum exposure route. Uro-fecal samples had the greatest potential as non-lethal samples compared to mucus and blood. In terms of future monitoring, combining lethal samples tested by ELISA assay with uro-fecal samples tested by nPCR could be the best strategy for detecting R. salmoninarum prevalence in a population as it reduces the overall number of fish required for sampling.


Asunto(s)
Enfermedades de los Peces/diagnóstico , Infecciones por Bacterias Grampositivas/veterinaria , Micrococcaceae/aislamiento & purificación , Salmón , Animales , Ensayo de Inmunoadsorción Enzimática/métodos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Enfermedades de los Peces/microbiología , Infecciones por Bacterias Grampositivas/diagnóstico , Infecciones por Bacterias Grampositivas/microbiología , Curva ROC
6.
J Health Pollut ; 7(16): 71-82, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30524842

RESUMEN

Background: Antifouling paints are enriched with biocides and employed in the maritime industry to protect moving and fixed surfaces from fouling activities of sea dwelling invertebrates. There is limited information on their effect on the non-target African catfish, Clarias gariepinus, a commonly consumed fish in Lagos. Objectives: This study investigated the effects of two commonly used antifouling paints (Berger TBT-free (A/F783 (H)), reddish brown color and Silka Marine lead based paint, pale orange color) on a non-target catfish species, Clarias gariepinus. Methods: The study involved an initial 96-hour acute toxicity assay followed by chronic toxicity evaluation (using 1/10th and 1/100th 96-hour median lethal concentration (LC50) values) for 28 days to determine the ability of the paints to induce micronucleus and red blood cell abnormalities, and histopathological as well as oxidative stress effects in the catfish.Examined anti-oxidative stress enzyme activities include superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and glutathione-s-transferase (GST). Results: Acute toxicity evaluation results indicated that the Berger paint was 16.1-times more toxic than Silka paint with 96-hour LC50 values of 0.71 mg/L and 11.49 mg/L, respectively. Results from the biochemical assay indicated significantly higher (P<0.05) levels of a lipid peroxidation product, malondialdehyde, in Silka-exposed catfish compared to the control. All enzymes showed significantly higher activities in Berger paint-exposed catfish compared to the control. There was evidence of micronucleated and binucleated cells in the red blood cells of fish exposed to both paints. Histopathological assessment indicated that the exposed fish gills showed evidence of abnormalities such as curved lamellae epithelial necrosis, epithelial lifting and hyperplasia. The liver samples of the catfish showed evidence of portal inflammation as well as mild to severe steatosis, while the gonads showed varying percentages of follicle degeneration. Conclusions: The present study combined an array of biomarkers to determine the negative health impacts of two commonly used antifouling paints on non-target catfish inhabiting Lagos Lagoon. Further in situ studies are recommended to determine the current status of the lagoon fish. Ethics Approval: Ethical approval was obtained from the Department of Zoology, University of Lagos, Post-Graduate Committee. Note that this work commenced before the establishment of the University of Lagos Ethical Committee for the use of animals and humans in scientific studies. The committee does not give retroactive approval but stands by existing approvals before its establishment. However, this study followed the World Medical Association principles on the treatment of animals used in research (https://www.wma.net/policies-post/wma-statement-on-animal-use-in-biomedical-research/), and also American Fisheries Society Guidelines for the Use of Fishes in Research (https://fisheries.org/policy-media/science-guidelines/guidelines-for-the-use-of-fishes-in-research/).

7.
J. Health Biol. Sci. (Online) ; 4(3): 193-197, jul-set/2016. tab
Artículo en Inglés | LILACS | ID: biblio-876858

RESUMEN

Introduction: Fish are usually exposed to higher microbial loads than land or air animals. The microbiota of fish mostly consists of Pseudomonas spp., Aeromonas spp., Shewanella putrefasciens, Acinetobacter spp. and Moraxella spp. Objective: to analyze the oral cavity, and skin tissue microbiota on the Nile tilapia (Oreochromis niloticus), a fish species raised commercially in Brazil. Methods: Samples were collected from the oral cavity and skin of 20 Nile tilapia specimens (Oreochromis niloticus), each weighing approximately 1,000 grams. The samples were cultures for quantitative analysis on sheep blood agar (SBA) and chromID™ CPS® agar (CPS). Results: Eleven different bacterial species were identified on CPS and SBA plates. Gram-negative species were the most prevalent, while gram-positive Globicatella spp, Streptococcus spp and Enterococcus faecalis were also found. Pseudomonas aeruginosa species were isolated from all samples. Gram-positive Enterococcus faecalis was found in 70 and 60% of the skin and oral samples, respectively. Conclusion: For all samples studied, the microbial load was less than 100,000 colony-forming units - CFU/g of tissue. This value is a cutoff standardized for the American Society of Microbiology to differentiate the causal agent from the colonizers. In light of this result and considering the absence of infectious signs in the fish samples, we conclude that the CFU values found in this study reflect a normal, non-infectious colonization/microbiota. (AU)


Introdução: Os peixes são normalmente expostos a cargas microbianas mais elevadas do que os animais em terra ou ar. O perfil da microbiota em peixes compreende principalmente Pseudomonas spp., Aeromonas spp., Shewanella putrefasciens, Acinetobacter spp., e Moraxella spp. Objetivo: analisar a microbiota da cavidade oral e do tecido da pele no Tilápia do Nilo (Oreochromis niloticus), comercialmente criado no Brasil. Métodos: Vinte espécimes de Tilápia do Nilo (Oreochromis niloticus), cada uma pesando cerca de 1.000 gramas, foram submetidas a coleta de amostras da cavidade oral e da pele. Estas amostras foram cultivadas quantitativamente em ágar sangue de carneiro (SBA) e chromID® CPS® agar (CPS). Resultados: Foram identificadas 11 diferentes espécies de bactérias em placas CPS e SBA. Os resultados mostram que bacilos gram-negativos são os mais prevalentes. Cocos gram-positivos como Globicatella spp, Streptococcus spp e Enterococcus faecalis também foram encontrados. Espécies de Pseudomonas aeruginosa foram isoladas a partir de todas as amostras. Enterococcus faecalis foi encontrado em 70 e 60% das amostras de pele e por via oral, respectivamente. Conclusão: Os resultados deste estudo mostram, para todas as amostras estudadas, uma carga de CFU de menos de 100.000 unidades formadoras de colonias - UFC / g de tecido. Este valor é um cutoff padronizado pela Sociedade Americana de Microbiologia, a fim de diferenciar o agente causal dos colonizadores. Diante destes resultados e considerando a ausência de sinais infecciosos nas amostras de peixes, conclui-se que os valores CFU's encontrados neste estudo consistem em colonização/ microbiota. (AU)


Asunto(s)
Microbiota , Cíclidos , Explotaciones Pesqueras
8.
Zootaxa ; 4103(1): 43-53, 2016 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-27394612

RESUMEN

Examination of specimens of the crayfish species Cambarus (Hiaticambarus) longirostris and two recently described crayfish revealed the existence of an undescribed species from the Flint River watershed in northern Alabama and southern Tennessee. Cambarus (Hiaticambarus) lentiginosus differs from C. longirostris, C. (Hiaticambarus) andersoni, and C. (Hiaticambarus) diupalma in aspects of carapace and chela morphology and pigmentation pattern. Cambarus (H.) lentiginosus possesses a median carina on the dorsal surface of the acumen of the rostrum, a distinctly enlarged tubercle near the base of the opposable surface of the dactyl, and a speckled pigmentation pattern over a light base color; these characters are lacking in other known Hiaticambarus species. The known range of the species is restricted to the Flint River watershed. Cambarus (H.) lentiginosus is considered Endangered using American Fisheries Society conservation categorization.


Asunto(s)
Astacoidea/clasificación , Alabama , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Astacoidea/anatomía & histología , Astacoidea/crecimiento & desarrollo , Tamaño Corporal , Ecosistema , Femenino , Masculino , Tamaño de los Órganos , Ríos , Tennessee
9.
Zootaxa ; 4058(2): 151-74, 2015 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-26701517

RESUMEN

Multivariate and univariate statistical analyses of morphometric data and examination of morphological characters of the crayfish species Cambarus (Hiaticambarus) longirostris revealed the existence of two undescribed species from populations previously considered to be C. longirostris in tributaries of the Tennessee River in north Alabama and central south Tennessee. Cambarus (Hiaticambarus) andersoni and Cambarus (Hiaticambarus) diupalma differed from C. longirostris and from each other in aspects of chela morphometrics and in the presence or absence of qualitative characters. Cambarus andersoni has a corneous spine on the base of the ventral surface of the rostrum that is absent in the other two species; C. diupalma abdominal pleura are acute whereas they are subtruncate in C. andersoni and in C. longirostris. The known range of both of the new species is restricted to northern tributaries of the Tennessee River in south Tennessee and north Alabama. Cambarus diupalma is considered Endangered and C. andersoni is considered Vulnerable using American Fisheries Society conservation categorization.


Asunto(s)
Astacoidea/clasificación , Alabama , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Astacoidea/anatomía & histología , Astacoidea/crecimiento & desarrollo , Tamaño Corporal , Ecosistema , Femenino , Masculino , Tamaño de los Órganos , Tennessee
10.
Zootaxa ; 3980(4): 526-46, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-26249970

RESUMEN

Cambarus (Jugicambarus) dubius Faxon, 1884 is a polychromatic montane burrowing crayfish with a long, turbulent taxonomic history since its original description by Walter Faxon in 1884. Over the years, many distinct color phases have been identified, with the majority of these being confined to a specific geographic or physiographic region in the central and southern Appalachians. Previous investigations of this species (e.g., Dewees 1972) were unable to discover consistent morphological differences among the various groups, and thus were unable to clarify what has long been considered a species complex. Due to lingering taxonomic issues, we herein re-describe, delimit and restrict the concept of C. dubius. We also describe a new species, Cambarus (Jugicambarus) pauleyi, from the same complex, which can be identified through the use of geographic distribution, coloration, and distinct morphological characters. Cambarus dubius sensu stricto, as defined here, is restricted to the "typical form" which has an overall orang-ish color pattern on the dorsal and lateral sides, with cream ventrally. The distribution of C. dubius s.s. is limited to the central and northern portions of the Allegheny Mountains and high elevations of the Appalachian Plateau in central West Virginia, western Maryland, and southcentral Pennsylvania. In contrast, C. pauleyi is endemic to high elevation wetlands (>700 m) in the Meadow and Greenbrier River basins in Greenbrier and Monroe counties, West Virginia. Cambarus pauleyi can be differentiated from C. dubius s.s. by 1) its blue dorsal coloration compared to the orange coloration of C. dubius s.s., 2) its large (palm depth/(palm length) ratio, and 3) its smaller (rostral width)/(rostral length) ratio. Cambarus pauleyi can be separated from other peripatric populations of C. dubius sensu lato that occur in the Meadow and Greenbrier River drainage by its 1) blue coloration compared to the orange and black coloration of the latter, 2) the smaller (palm depth)/(palm length) ratio in C. pauleyi, and 3) the deeply excavated rostrum of C. dubius compared to the moderately excavated rostrum of C. pauleyi. Cambarus pauleyi can be easily differentiated from both taxa by the presence of two subpalmer tubercles. Both C. dubius s.s and peripatric C. dubius lack subpalmer tubercles. Cambarus pauleyi has an extremely narrow geographic distribution and has possibly experienced a significant range reduction due to the conversion of wetlands into pastures, and should be considered "Endangered" according to American Fisheries Society listing criteria (Taylor et al. 2007).


Asunto(s)
Astacoidea/anatomía & histología , Astacoidea/clasificación , Animales , Femenino , Masculino , West Virginia
11.
J Aquat Anim Health ; 26(3): 194-201, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25229492

RESUMEN

Abstract The development and characterization of a new cell line, derived from the ovary of Largemouth Bass Micropterus salmoides, is described. Gonad tissue was collected from Largemouth Bass that were electrofished from Oneida Lake, New York. The tissue was processed and grown in culture flasks at approximately 22°C for more than 118 passages during an 8-year period from 2004 to 2011. The identity of these cells as Largemouth Bass origin was confirmed by sequencing a portion of the cytochrome b gene. Growth rate at three different temperatures was documented. The cell line was susceptible to Largemouth Bass virus (LMBV) and its replication was compared with that of Bluegill Lepomis macrochirus fry (BF-2), one of the cell lines recommended for LMBV isolation by the American Fisheries Society Fish Health Section Blue Book. Quantitative PCR results from the replication trial showed the BF-2 cell line produced approximately 10-fold more LMBV copies per cell than the new Largemouth Bass cell line after 6 d, while the titration assay showed similar quantities in each cell line after 1 week. Received February 18, 2014; accepted April 16, 2014.


Asunto(s)
Lubina , Susceptibilidad a Enfermedades/veterinaria , Animales , Línea Celular , Infecciones por Virus ADN , Enfermedades de los Peces , Perciformes
12.
J Vet Diagn Invest ; 25(3): 341-51, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23536613

RESUMEN

Histology is often underutilized in aquatic animal disease screening and diagnostics. The agreement between histological classifications of infection and results using diagnostic testing from the American Fisheries Society's Blue Book was conducted with 4 common salmon pathogens: Aeromonas salmonicida, Renibacterium salmoninarum, Ceratomyxa shasta, and Nanophyetus salmincola. Adult Chinook salmon (Oncorhynchus tshawytscha) in Oregon were evaluated, and agreement between tests was calculated. Live and dead (both pre- and postspawning) salmon were collected from the Willamette River, Oregon, its tributaries, the Willamette Hatchery, and after holding in cool, pathogen-free water during maturation at Oregon State University. Sensitivity and specificity of histology compared to Blue Book methods for all fish, live fish only, and dead (pre- and postspawned combined) fish only were, respectively, as follows: A. salmonicida (n = 105): specificity 87.5%, 87.5%, 87.5% and sensitivity 38.6%, 14.8%, 60.0%; R. salmoninarum (n = 111): specificity 91.9%, 85.7%, 97.7% and sensitivity 16.0%, 7.1%, 27.2%; C. shasta (n = 136): specificity 56.0%, 63.3%, 28.6% and sensitivity 83.3%, 86.2%, 71.4%; N. salmincola (n = 228): specificity 68.2%, 66.7%, not possible to calculate for dead fish and sensitivity 83.5%, 80.5%, 87.3%. The specificity was good for bacterial pathogens. This was not the case for C. shasta, likely due to detection of presporogenic forms only by histology. Sensitivity of histology for bacterial pathogens was low with the exception of dead fish with A. salmonicida. Kappa analysis for agreement between Blue Book and histology methods was poor to moderate. However, histological observations revealed the presence of other pathogens that would not be detected by other methods.


Asunto(s)
Enfermedades de los Peces/microbiología , Agua Dulce , Infecciones por Bacterias Gramnegativas/veterinaria , Infecciones por Bacterias Grampositivas/veterinaria , Enfermedades Parasitarias en Animales/parasitología , Salmón , Animales , Enfermedades de los Peces/diagnóstico , Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Grampositivas/diagnóstico , Micrococcaceae , Myxozoa/aislamiento & purificación , Infecciones por Nematodos/diagnóstico , Infecciones por Nematodos/veterinaria , Enfermedades Parasitarias en Animales/diagnóstico , Sensibilidad y Especificidad
13.
Proc Natl Acad Sci U S A ; 109(12): 4696-701, 2012 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-22392996

RESUMEN

Marine spatial planning (MSP) is an emerging responsibility of resource managers around the United States and elsewhere. A key proposed advantage of MSP is that it makes tradeoffs in resource use and sector (stakeholder group) values explicit, but doing so requires tools to assess tradeoffs. We extended tradeoff analyses from economics to simultaneously assess multiple ecosystem services and the values they provide to sectors using a robust, quantitative, and transparent framework. We used the framework to assess potential conflicts among offshore wind energy, commercial fishing, and whale-watching sectors in Massachusetts and identify and quantify the value from choosing optimal wind farm designs that minimize conflicts among these sectors. Most notably, we show that using MSP over conventional planning could prevent >$1 million dollars in losses to the incumbent fishery and whale-watching sectors and could generate >$10 billion in extra value to the energy sector. The value of MSP increased with the greater the number of sectors considered and the larger the area under management. Importantly, the framework can be applied even when sectors are not measured in dollars (e.g., conservation). Making tradeoffs explicit improves transparency in decision-making, helps avoid unnecessary conflicts attributable to perceived but weak tradeoffs, and focuses debate on finding the most efficient solutions to mitigate real tradeoffs and maximize sector values. Our analysis demonstrates the utility, feasibility, and value of MSP and provides timely support for the management transitions needed for society to address the challenges of an increasingly crowded ocean environment.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Ecosistema , Animales , Catálisis , Conservación de los Recursos Naturales/economía , Explotaciones Pesqueras/economía , Peces , Biología Marina/economía , Biología Marina/organización & administración , Massachusetts , Modelos Biológicos , Modelos Económicos , Nephropidae , Océanos y Mares , Ballenas
14.
Environ Monit Assess ; 172(1-4): 67-89, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20127407

RESUMEN

A 1988 survey, funded by the US Environmental Protection Agency (EPA) and conducted by the American Fisheries Society, identified the need to standardize the approaches for evaluating risks and developing fish consumption advisories that are comparable across different jurisdictions. A major tool for evaluating the progress in developing such nationally consistent information is EPA's web-based National Listing of Fish Advisories (NLFA) database, which has archived fish advisory information since 1993. The NLFA comprises both a database and Geographic Information System mapping components that are implemented using the National Hydrography Dataset (NHD). EPA and the US Geological Survey have developed an enhanced NHD product (NHDPlus) that is applied to define an interstate waters framework for the conterminous USA. This NHDPlus-based framework provides an efficient watershed-oriented approach for identifying interstate advisories from NLFA. We provide summaries of (1) the degree of consistency documented for inland waters where states have issued advisories for shared interstate NHD reaches and (2) the patterns for interstate advisories organized according to the ecoregions developed for EPA's Wadeable Streams Assessment. Approaches are also discussed for addressing interstate consistency issues for fish advisories in coastal waters making use of the NHDPlus combined with other nationally consistent frameworks, such as the 12-digit hydrologic unit code subwatersheds in the Watershed Boundary Dataset. Probability survey methods are recommended as a way to promote increased interjurisdictional consistency in the development of the monitoring and risk assessment conclusions reflected in NLFA, as well as in other EPA water quality-based programs.


Asunto(s)
Explotaciones Pesqueras/legislación & jurisprudencia , Animales , Explotaciones Pesqueras/normas , Peces , Sistemas de Información Geográfica , Medición de Riesgo , Estados Unidos , United States Environmental Protection Agency
15.
Am Nat ; 176(4): 385-93, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20735261

RESUMEN

Detailed natural history coupled to experimental ecology has provided a rich harvest of insights into how natural communities in all ecosystems function, insights that cannot be gleaned from macroecological analyses. That detail, generated by small-spatial-scale but often lengthy experiments, is essential to managing and even restoring ecosystems. My essay focuses primarily on the ecology of exposed rocky intertidal shores, but I believe the derived implications are generalizable to all ecosystems. A mainly experimental approach has tended to avoid a preoccupation with niches but instead has focused on the ecological roles exercised by particular species. Attention to roles has produced a growing appreciation for trophic cascades and their consequences, with obvious implications for the management of fisheries and the conservation significance of apex predators. Some studies are more phenomenological and others more reductionist in focus, but all provide pathways toward understanding abundance and body size variation or a miscellany of indirect effects. Microecology in all ecosystems should continue to prosper independently of a macroecological, predominately terrestrial perspective.


Asunto(s)
Cadena Alimentaria , Humedales , Animales , Ecología/métodos , Ecosistema , Geografía , Densidad de Población , Dinámica Poblacional
16.
Conserv Biol ; 24(5): 1249-58, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20337684

RESUMEN

Conserving rare species and protecting biodiversity and ecosystem functioning depends on sound information on the nature of rarity. Rarity is multidimensional and has a variety of definitions, which presents the need for a quantitative classification scheme with which to categorize species as rare or common. We constructed such a classification for North American freshwater fishes to better describe rarity in fishes and provide researchers and managers with a tool to streamline conservation efforts. We used data on range extents, habitat specificities, and local population sizes of North American freshwater fishes and a variety of quantitative methods and statistical decision criteria, including quantile regression and a cost-function algorithm to determine thresholds for categorizing a species as rare or common. Species fell into eight groups that conform to an established framework for rarity. Fishes listed by the American Fisheries Society (AFS) as endangered, threatened, or vulnerable were most often rare because their local population sizes were low, ranges were small, and they had specific habitat needs, in that order, whereas unlisted species were most often considered common on the basis of these three factors. Species with large ranges generally had few specific habitat needs, whereas those with small ranges tended to have narrow habitat specificities. We identified 30 species not designated as imperiled by AFS that were rare along all dimensions of rarity and may warrant further study or protection, and we found three designated species that were common along all dimensions and may require a review of their imperilment status. Our approach could be applied to other taxa to aid conservation decisions and serve as a useful tool for future revisions of listings of fish species.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales/métodos , Ecosistema , Especies en Peligro de Extinción/estadística & datos numéricos , Peces/clasificación , Animales , Demografía , Agua Dulce , América del Norte , Dinámica Poblacional , Análisis de Regresión , Especificidad de la Especie
17.
Acta amaz ; 39(1): 121-138, mar. 2009. ilus, graf, mapas, tab
Artículo en Portugués | LILACS | ID: lil-515755

RESUMEN

São raros os estudos envolvendo o uso múltiplo de recursos naturais por populações amazônicas. Este trabalho apresenta um panorama de como os índios Deni, habitantes da região de interflúvio entre dois dos maiores afluentes de água branca da bacia amazônica, os rios Juruá e Purus, utilizam dos recursos disponíveis em seu território. Os Deni são, atualmente, índios que vivem da exploração de recursos da terra firme e de regiões alagadas. São um misto de horticultores e caçadores/coletores, que utilizam toda a sua área para a obtenção de recursos para subsistência. Como regra, deslocam periodicamente seus assentamentos, evitando o esgotamento local de recursos, e provocando a modificação local do ambiente. Esta alteração aumenta temporariamente a disponibilidade de alimento. Áreas com aldeias, pomares e roçados abandonados, por sua vez, tornam-se locais onde se concentram inúmeros recursos da flora e da fauna, posteriormente explorados. O impacto provocado por este sistema é aparentemente mínimo. Os Deni estão contextualizados na periferia de um sistema capitalista, onde a única fonte de renda para adquirir bens que são hoje considerados pelos índios como indispensáveis para sua sobrevivência são os recursos naturais. Estes são e continuarão sendo explorados de maneira a produzir um excedente a ser comercializado para a obtenção de uma série de produtos industrializados, independentemente das opiniões externas. É sobre este patamar que devemos avaliar a sustentabilidade do atual manejo da área.


Studies concerning the use of multiple natural resources by Amazonian indians are scarce. This work presents a portrait of how the Deni Indians, inhabitants of an area between two of the most important white-water rivers of the Amazon basin (Juruá and Purus Rivers), exploit natural resources in their territory. The Deni exploit both the upland and floodplain forests. They are a mix of horticulturalists and hunter-gatherers, using their whole territory to obtain what they need to live. As a rule, they move their settlements periodically, avoiding local resource depletion. The Deni modify the landscape at a local level, causing an increase in resource availability. Abandoned villages, fruit orchards and crops are places where floristic and faunistic resources concentrate and are systematically exploited. The impacts of such management are apparently minimal. For the Deni society natural resources are the only way to get goods for survival, but it is inserted in the periphery of a capitalist system which exploits and will continue to exploit natural resources in order to produce a surplus for the acquisition of industrialized products, independently of external judgements. This should be the starting point to evaluate sustainability in this local management system.


Asunto(s)
Ecosistema Amazónico , Agricultura , Antropología Cultural , Indios Sudamericanos , Explotaciones Pesqueras
18.
Evol Appl ; 2(3): 245-59, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25567878

RESUMEN

There is increasing evidence that fishing may cause rapid contemporary evolution in freshwater and marine fish populations. This has led to growing concern about the possible consequences such evolutionary change might have for aquatic ecosystems and the utility of those ecosystems to society. This special issue contains contributions from a symposium on fisheries-induced evolution held at the American Fisheries Society Annual Meeting in August 2008. Contributions include primary studies and reviews of field-based and experimental evidence, and several theoretical modeling studies advancing life-history theory and investigating potential management options. In this introduction we review the state of research in the field, discuss current controversies, and identify contributions made by the papers in this issue to the knowledge of fisheries-induced evolution. We end by suggesting directions for future research.

19.
Plant Dis ; 90(12): 1550, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30780976

RESUMEN

Phytophthora infestans is known worldwide as the destructive, late blight pathogen of potatoes and tomatoes. However, erratic reports dating back to 1856 also have shown it to be pathogenic on petunia (Petunia × hybrida), although it has not been regarded as an important pathogen on this host (4). Recently, reports from North America showed that P. infestans is of commercial importance in greenhouse-grown petunias (2), and that late blight-infected petunias may serve as inoculum to tomatoes growing in the same greenhouse (1,2). In the Western Cape Province of South Africa, two petunia samples were received at the Stellenbosch University Plant Disease Clinic in 2005 that showed symptoms resembling P. infestans infections. The two samples were from nurseries where petunias were either grown under shading nets or in a greenhouse. In the greenhouse-grown petunias, the presumptive late blight infections resulted in substantial losses to the grower. Symptoms included gray, slightly sunken leaf lesions with white sporulation mainly on the adaxial side of the leaves. Leaflets of the petunias were incubated in moist chambers, and sporangia sporulating from lesions were identified morphologically as being P. infestans (3). Subsequently, one isolate was cultured onto synthetic media by carefully transferring sporangia from a lesion with the tip of a bended glass rod onto wheat medium (120 g/L of crushed wheat seeds, blended, boiled and filtered through cheesecloth, plus 15 g of sucrose and agar). The identity of the culture was further confirmed through sequence analyses of the internal transcribed spacer regions (GenBank Accession No. DQ479409). The isolated P. infestans strain (STE-U 6134) has been submitted to the Stellenbosch University culture collection. Inoculum for the pathogenicity tests was produced by first flooding 14-day-old cultures with sterile distilled water to obtain a 2 × 104/ml sporangial suspension, followed by zoospore induction at 4°C. A mixture of petunia cultivars (n = 24) were spray inoculated to runoff with the zoospore induced sporangial suspension. Control plants were sprayed with sterile distilled water. Inoculated plants were incubated at 22 to 25°C and high relative humidity (≥93%) within perspex humidity chambers (60 × 30 × 60 cm) lined with a wet sheet of chromatography paper. The experiment was repeated twice. The first late blight symptoms similar to those of the submitted samples appeared 5 to 7 days after inoculation, with some lesions containing profuse white mycelia and sporangiophores typical for P. infestans. The pathogen was reisolated from the leaf lesions, completing Koch's postulate. To our knowledge, this is the first report of P. infestans causing damage on petunias in South Africa. Future studies should be aimed at investigating whether late blight-infected petunias provide an important source of inoculum for potatoes and tomatoes, which are widely grown in the Western Cape Province of South Africa. References: (1) M. C. Becktell et al. Plant Dis. 89:1000, 2005. (2) K. L. Deahl and D. K. Farel. Plant Dis. 87:1004, 2003. (3) D. C. Erwin and O. K. Ribeiro, Phytophthora Diseases Worldwide. The American Phytopathological Society St. Paul, MN, 1996. (4) J. M. Hirst and W. C. Moore. Phytophthora infestans on petunia and datura. Page 76 in: Plant Pathology-A Record of Current Work on Plant Diseases and Pests. Vol. 6. Ministry of Agriculture, Fisheries and Food Plant Pathology Laboratory, Harpenden, England, 1957.

20.
Zebrafish ; 3(3): 267-9, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-18377208

RESUMEN

Dr. Contreras Balderas is Professor Emeritus in the Department of Biology at Universidad Autonoma de Nuevo Leon (Monterrey, Mexico). He received a Master's degree and Ph.D. in Biological Sciences from Tulane University (New Orleans, LA) and wrote his dissertation on Ichthyology. He was awarded the President's Excellence Award of the American Fisheries Society. Dr. Contreras Balderas is Founder, President, and Honorary Member of the Mexican Society of Zoology, the Ichthyological Society of Mexico, and the Desert Fishes Council, is an ex-officio member of the Coalition for the Sustainable Development of the Rio Grande/Rio Bravo, U.S. & Mexico, and is a member of the U.S. Fish and Wildlife's Rio Grande Fishes Recovery Team. Dr. Contreras Balderas's areas of expertise include fish faunas, fishes at risk, exotic species, aquatic restoration, environmental impacts as detected by fishes, integral conservation, integral basin/ecosystem management, and ecological evaluation of integrity in basins.

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