174 resultados para WOLVES CHRYSOCYON-BRACHYURUS


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One out of four specimens of sharks, Carcharhinus brachyurus (Günther, 1860), captured off the southern Brazilian Coast, harboured cestodes identified as Dasyrhynchus pacificus Robinson, 1965, of which the adult form is now described and referred as ocurring in Brazil.

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The Iberian wolf (Canis lupus) is the top predator in the Iberian environments in which it lives, feeding on a wide range of species, thus encountering a wide range of disease agents. Therefore, the wolf can serve as sentinel of environmental contamination with pathogens. We investigated the exposure of free-living wolves to 14 serovars of Leptospira interrogans sensu lato. Kidney samples from 49 wolves collected from 2010-2013 in northwestern Spain were analysed by culture, direct immunofluorescence and polymerase chain reaction. Tissue fluids were analysed for antibodies by a microscopic agglutination test. Ten wolves (observed prevalence: 20%, 95% confidence interval = 11-33%) showed evidence of contact with leptospires, eight through direct detection and nine through serology (7 wolves were positive according to both techniques). Titres below the cut-off level were also detected in seven cases. Serovars confirmed were Canicola (n = 4), Icterohaemorrhagiae (n = 3) and Sejroë, Ballum and Grippotyphosa (n = 1 each), indicating that wolves were infected with serovars for which dogs, rodents and ungulates, are the natural hosts and supporting the utility of the wolf and other large predators as environmental sentinels for pathogens.

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Des de l’any 2000 es té constància de la presencia del llop a Catalunya. Des de llavors, com a mínim 14 llops diferents han entrat i sortit del territori català, encara que cap d’ells s’ha assentat de manera permanent. L’estudi analitza l’entorn català utilitzant GIS, creant un model d’adequació de l’hàbitat tenint en compte les següents variables: la distància a la carretera més propera, la biomassa disponible a la zona, l’altitud i el tipus i tant per cent de recobriment. El model es basa en la informació obtinguda mitjançant la consulta a experts tant del llop com del territori català, així com en una recerca bibliogràfica sobre l’adequació de l’hàbitat del llop. L’enquesta que es dirigí als experts té en compte els valors que cada variable pot prendre dins l’àrea d’estudi, estableix rangs dels valors de cada variable i pregunta als experts com cada rang pot afectar a l’adequació de l’hàbitat pel llop. Els resultats mostren com bona part de la zona Nord de Catalunya té unes condicions adequades perquè el llop pugui arribar a reproduir-s’hi. Es desenvolupa també una anàlisi dels possibles punts de conflicte humà-llop i una superposició dels espais protegits amb les zones més adequades per l’establiment del llop.

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Wolves in Italy strongly declined in the past and were confined south of the Alps since the turn of the last century, reduced in the 1970s to approximately 100 individuals surviving in two fragmented subpopulations in the central-southern Apennines. The Italian wolves are presently expanding in the Apennines, and started to recolonize the western Alps in Italy, France and Switzerland about 16 years ago. In this study, we used a population genetic approach to elucidate some aspects of the wolf recolonization process. DNA extracted from 3068 tissue and scat samples collected in the Apennines (the source populations) and in the Alps (the colony), were genotyped at 12 microsatellite loci aiming to assess (i) the strength of the bottleneck and founder effects during the onset of colonization; (ii) the rates of gene flow between source and colony; and (iii) the minimum number of colonizers that are needed to explain the genetic variability observed in the colony. We identified a total of 435 distinct wolf genotypes, which showed that wolves in the Alps: (i) have significantly lower genetic diversity (heterozygosity, allelic richness, number of private alleles) than wolves in the Apennines; (ii) are genetically distinct using pairwise F(ST) values, population assignment test and Bayesian clustering; (iii) are not in genetic equilibrium (significant bottleneck test). Spatial autocorrelations are significant among samples separated up to c. 230 km, roughly correspondent to the apparent gap in permanent wolf presence between the Alps and north Apennines. The estimated number of first-generation migrants indicates that migration has been unidirectional and male-biased, from the Apennines to the Alps, and that wolves in southern Italy did not contribute to the Alpine population. These results suggest that: (i) the Alps were colonized by a few long-range migrating wolves originating in the north Apennine subpopulation; (ii) during the colonization process there has been a moderate bottleneck; and (iii) gene flow between sources and colonies was moderate (corresponding to 1.25-2.50 wolves per generation), despite high potential for dispersal. Bottleneck simulations showed that a total of c. 8-16 effective founders are needed to explain the genetic diversity observed in the Alps. Levels of genetic diversity in the expanding Alpine wolf population, and the permanence of genetic structuring, will depend on the future rates of gene flow among distinct wolf subpopulation fragments.

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In the early 1900s, the wolf (Canis lupus) was extirpated from France and Switzerland. There is growing evidence that the species is presently recolonizing these countries in the western Alps. By sequencing the mitochondrial DNA (mtDNA) control region of various samples mainly collected in the field (scats, hairs, regurgitates, blood or tissue; n = 292), we could (1) develop a non-invasive method enabling the unambiguous attribution of these samples to wolf, fox (Vulpes vulpes) or dog (Canis familiaris), among others; (2) demonstrate that Italian, French and Swiss wolves share the same mtDNA haplotype, a haplotype that has never been found in any other wolf population world-wide. Combined together, field and genetic data collected over 10 years corroborate the scenario of a natural expansion of wolves from the Italian source population. Furthermore, such a genetic approach is of conservation significance, since it has important consequences for management decisions. This first long-term report using non-invasive sampling demonstrates that long-distance dispersers are common, supporting the hypothesis that individuals may often attempt to colonize far from their native pack, even in the absence of suitable corridors across habitats characterized by intense human activities.

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Com o objetivo de estudar a ocorrência de nematoides fitoparasitos em frutíferas cultivadas na região noroeste do Paraná, realizou-se um levantamento, envolvendo 124 amostras de solo e raízes coletadas de 19 espécies de frutíferas, em 15 municípios, no período de dezembro/2007 a fevereiro/2009. As amostras foram submetidas a extrações e avaliadas sob microscópio óptico. Foram constatados nove diferentes gêneros de nematoides. Em citros, a espécie mais frequente e abundante foi Tylenchulus semipenetrans, sendo também recuperados das amostras os gêneros Meloidogyne, Pratylenchus, Helicotylenchus, Xiphinema, Trichodorus, Mesocriconema e Dolichodorus. Nas demais frutíferas, os gêneros observados foram Meloidogyne, Pratylenchus, Helicotylenchus e Hemicycliophora. A maior abundância de Pratylenchus brachyurus ocorreu em abacaxizeiro, Meloidogyne incognita em figueira e caquizeiro, e Helicotylenchus dihystera e H. multicinctus em bananeira. Os principais gêneros de fitonematoides foram constatados em aproximadamente 50% das amostras, podendo representar risco para fruteiras da região se não manejados adequadamente.

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Following protection measures implemented since the 1970s, large carnivores are currently increasing in number and returning to areas from which they were absent for decades or even centuries. Monitoring programmes for these species rely extensively on non-invasive sampling and genotyping. However, attempts to connect results of such studies at larger spatial or temporal scales often suffer from the incompatibility of genetic markers implemented by researchers in different laboratories. This is particularly critical for long-distance dispersers, revealing the need for harmonized monitoring schemes that would enable the understanding of gene flow and dispersal dynamics. Based on a review of genetic studies on grey wolves Canis lupus from Europe, we provide an overview of the genetic markers currently in use, and identify opportunities and hurdles for studies based on continent-scale datasets. Our results highlight an urgent need for harmonization of methods to enable transnational research based on data that have already been collected, and to allow these data to be linked to material collected in the future. We suggest timely standardization of newly developed genotyping approaches, and propose that action is directed towards the establishment of shared single nucleotide polymorphism panels, next-generation sequencing of microsatellites, a common reference sample collection and an online database for data exchange. Enhanced cooperation among genetic researchers dealing with large carnivores in consortia would facilitate streamlining of methods, their faster and wider adoption, and production of results at the large spatial scales that ultimately matter for the conservation of these charismatic species.

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This study investigates the use of wild animal hair of C. brachyurus, C. thous and L. pardalis as biomonitors of trace metal at Parque Nacional das Emas, Brazil. Results reveal a strong correlation between Cd and Pb as well as Cu and Zn, which suggests a single source of emission. Most metals showed a lower or equal concentration than those obtained in previous studies. The research shows that monitoring may be performed only with Zn, Pb, Cd, and Cr because of statistical similarity and of a non-natural occurrence of large amounts of the material under analysis.

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O trabalho teve o objetivo de avaliar as populações de fitonematóides associados à cultura da mandioca, plantada em sucessão à cultura do inhame, em 22 propriedades rurais do Recôncavo da Bahia. Adicionalmente, foram feitos testes de hospedabilidade com as variedades de mandioca 'Cigana' e 'Talo Roxo', ao nematóide Scutellonema bradys. Foram constatadas as presenças dos seguintes nematóides: Pratylenchus brachyurus, Scutellonema bradys, Meloidogyne incognita e Rotylenchulus reniformis, nas raízes e amostras de solo. Além dos nematóides, Tylenchus sp., Aphelenchus sp., Meloidogyne incognita, Mesocriconema sp., Aphelenchoides sp., Helicotylenchus presente apenas nas amostras de solos. O teste de hospedabilidade demostrou que as variedades de mandioca estudadas não são hospedeiras de Scutellonema bradys.

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Suurpetojen kannanhoitoon, ja etenkin suden kannanhoitoon liittyvä monitahoinen konfl ikti esiintyy jännitteinä paikallisyhteisöjen ja keskushallinnon, maaseudun ja kaupunkien sekä maallikoiden ja tutkijoiden välillä. Suurpetopolitiikan legitimiteettikriisi näkyy kansallisen kannanhoidon tavoitteiden ja toimenpiteiden kiistämisenä passiivisin ja aktiivisin toimin. Tällä ajankohtaisella ongelmalla on mittavat historialliset juuret. Luonnon ja ihmisen välinen suhde on ollut jatkuvaa tasapainottelua konfl iktien ja niiden hallinnan kanssa, ja suurpedot ovat väistämättä olleet konfl iktin keskiössä lajityypillisten piirteidensä vuoksi. Tämän tutkimuksen tavoitteena on osoittaa ympäristöhistoriallisen tutkimusotteen kautta suomalaisen vahinkoeläinhistorian keskeiset toimet ja toimijat, sekä ymmärtää vahinkoeläinten kannanhoidon tavoite- ja toimenpideasettelun vaikutukset eläinpopulaatioihin historiallisessa ja ekologisessa kontekstissa. Tutkimuksen toinen tavoite on tuottaa synteesi nykypäivän suurpetojen kannanhoidon tavoite- ja toimenpiteiden tarkoituksenmukaisuudesta ja vaikuttavuudesta historiallisessa kontekstissa ja esittää uudenlainen lähestymismalli sosiaalisesti kestävämmälle suurpetopolitiikalle. Vahinkoeläinhistoriaa käsitellään deduktiivisella ja rekonstruktiivisella tutkimusotteella käyttäen aineistona lakitekstejä, maksettuja tapporahoja, sanomalehtikirjoituksia, sidosryhmien kirjoituksia sekä eläintieteellisiä julkaisuja. Etenkin laeissa ja asetuksissa eri eläimistä asetetut tapporahat ja toisaalta saalistilastojen perusteella maksetut palkkiot on nostettu tässä tutkimuksessa merkittävään rooliin asenteiden tulkinnan välineenä. Tarkastelu ulotetaan nisäkkäiden lisäksi myös lintuihin, jotka ovat edellä mainitun aineiston valossa olleet merkittävä vainottu eläinryhmä. Nykypäivän petokonfl iktin tarkastelussa keskiöön nostetaan suurpetoasenteet, niiden muodostuminen ja vaikutus suurpetopolitiikan tavoitteiden ja toimenpiteiden kiistämisessä. Suurpetopolitiikan legitimiteettikriisiä tarkastellaan paikallisten uhmakkuutena hallintoa kohtaan ja tulkinta keinoista puuttua sosiopoliittiseen rikokseen rakennetaan tätä ajatusta vasten. Suurpetojen salakaatajat toimivat yhteisönsä puolesta ja saavat tukensa toimilleen yhteisöltään. Sosiopoliittinen rikos ei siten ole ainoastaan salakaatajien vaan sen sijaan yhteisön yhteinen. Salakaatajat ja paikallisyhteisö pyrkivät häivyttämään yhteiskunnassa viranomaisten ja sidosryhmien taholta toimintaan liittämää stigmaa ja siten oikeuttamaan tekonsa vallitsevissa olosuhteissa. Arvoristiriitoihin perustuvat konfl iktit ovat haasteellisia hallita ja lähtökohtana on oltava ymmärrys siitä, että etenkin suteen liittyvät jännitteet ja ristiriidat ihmisten välisissä suhteissa ovat väistämättömiä. Tunnistamalla historiallisen aineiston merkittävyys nykypäivän ongelmakeskeisen kannanhoidon ratkaisun tietopohjana on mahdollista rakentaa sosiaalisesti kestävämpää suurpetojen kannanhoitoa. Tässä väitöskirjatyössä painotetaan suurpetoihin liittyen ajatusta, jonka mukaan paikallisilta suurpetoalueilla eläviltä ihmisiltä tai sidosryhmien edustajilta ei edellytetä arvomaailman muuttumista, vaan hyväksytään heidän käsityksensä suurpetojen roolista vahingontekijöinä. Sen sijaan vahvistetaan suurpetojen välineellistä roolia paikallisyhteisöjen resurssina ja oleellisten sidosryhmien roolia yhteisön toimijoina psykologisen omistajuuden rakentamisen kautta. Suurpetojen kestävä kannanhoito vaatii siten riistahallinnon toimintakulttuurin muutosta ja uudenlaista suhdetta yhteiskunnan eri toimijoihin.

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El trabajo de grado se desarrollará a partir del análisis del liderazgo y el poder como característica de éste, desde una visión ecológica, lo cual constituye un aspecto de gran importancia en los estudios de administración. Primero, se abordará el significado de liderazgo y la importancia que este representa dentro de las organizaciones, a través de la generación de procesos que llevan a la organización a su evolución y desarrollo. Posteriormente se abordará el tema de poder en relación con la comprensión del efecto que este puede tener sobre las interacciones que se dan entre las personas de la organización. Finalmente, se estudiará también desde la ecología, como el poder ejercido por los líderes puede influir en la forma en que estos agentes, es decir personas, procesos e interacciones, interactúan para movilizar a la organización. De esta forma, se asume el poder como un aspecto importante dentro del estudio del liderazgo, en cuanto éste puede afectar la forma en que las personas son lideradas al interior de la organización.

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El interés del presente estudio de caso es analizar la estrategia de securitización implementada por el Presidente de la Republica de Uzbekistán Islam Karimov sobre el Movimiento Islámico de Uzbekistán. Se describe y se explica cómo desde las lógicas históricas y étnicas acontecidas en Asia Central, se pueden comprender los alcances internacionales de la confrontación antagónica ejercida entre uzbekos al apoyar ideas de corte secular e islamista. Así, siguiendo los parámetros establecidos por Barry Buzan con respecto a la securitización, se puede llegar a identificar la creación de una agenda de seguridad uzbeka en la región de Asia Central, cuyos logros permitieron disminuir el riesgo de la amenaza insurgente.

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El objetivo de esta monografía es examinar la transformación de la doctrina de seguridad de la OTAN en la Post-Guerra Fría y sus efectos en la intervención en la República de Macedonia. La desintegración del bloque soviético implicó la variación en la definición de las amenazas que atentan contra la supervivencia de los países miembro de la Alianza Atlántica. A partir de la década de los noventa, los conflictos de naturaleza interétnica pasaron a formar parte de los riesgos que transgreden la seguridad de los Aliados y la estabilidad del área Euro-Atlántica. Por lo anterior, la OTAN intervino en aquellos Estados en los que prevalecían las confrontaciones armadas interétnicas, como por ejemplo: en Macedonia. Allí, la Alianza Atlántica ejecutó operaciones de gestión de crisis para contrarrestar la amenaza. El fenómeno a estudiar en esta investigación será analizado a partir del Realismo Subalterno y de la Teoría de la Seguridad Colectiva.

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The range of the Gray Wolf (Canis lupus), once covering most of North America, has been drastically reduced by an estimated 95% due to habitat loss and extermination by humans. The wolf was extirpated from Maine in the 1800’s. Wolf reintroductions have been suggested for Maine, but there is some debate about how much land is suitable for wolves. I developed a wolf habitat suitability analysis using ArcGIS and data from the Maine Office of GIS and the United States National Atlas. The model incorporates land cover, presence of major roads and railways, conservation land, industrial, non-industrial, and public woodlot ownership, distance from major points of population, deer population, and slope. The model results show areas of high and low wolf suitability in Maine. The model suggests that the best potential habitat for wolves in Maine is situated in the northwest of the state. Possible future reintroductions or natural colonization from other areas would have the highest likelihood of survival in these areas.

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Maine has been identified as holding potential for the reintroduction of wolves. Due to the long ranges of wolves, it is beneficial to map potential corridors of movement. This project analyzes the best routes for movement from suitable habitats in New York to suitable habitats in Maine. It shows the paths likely to be taken by wolves, based on their affinity for mixed and coniferous forest and their avoidance of areas of high road density. These corridors are identified using least cost path analysis and take into account topography as well as forest and road densities.