PDF superior Trophic diversity of the otter (Lutra lutra L.) in temperate and Mediterranean freshwater habitats

Trophic diversity of the otter (Lutra lutra L.) in temperate and Mediterranean freshwater habitats

Trophic diversity of the otter (Lutra lutra L.) in temperate and Mediterranean freshwater habitats

According to the latitudinal gradient in diversity, an increased trophic diversity of the otter in southern latitudes could be related to a higher abundance and availability of non-fish prey in these areas. In fact, at least reptiles and insects are specially abundant in Mediterranean Europe (Blondel & Aronson 1999), where the warm weather conditions allow them to reach large sizes and to be active most of the year. Moreover, the recent spread of the introduced American crayfish (Procambarus clarkii, Girard) has changed the diet of otters and other predators in many Mediterranean habitats (Delibes & Adrián, 1987; Beja, 1996; Correia, 2001), crayfish becoming an important prey. However, a higher availability of alternative prey makes possible, but not forces, an increase of trophic diversity. Besides this, it is usually necessary a reduction in the abundance or availability of the favourite prey (Stephens & Krebs, 1986). Erlinge (1968) stated that captive otters preferred to predate upon fish, and apparently fish are the otter’s staple prey whenever abundant, even under Mediterranean conditions. In fact, otters have an almost exclusive
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FISH BIOMASS AND OTTER REPRODUCTION IN A MOUNTAIN RIVER OF THE SOUTHEAST SPAIN

FISH BIOMASS AND OTTER REPRODUCTION IN A MOUNTAIN RIVER OF THE SOUTHEAST SPAIN

During the fish sampling, only brown trouts were captured, 81 individuals with a total weight of 6263 g. The estimated total biomass was 6697 g or 13,83 g/m 2 (r = -0,99, p<0,001), when the lowest seasonal trophic availability was present (see methods). The high dependence on brown trout is a consequence of the low taxonomic availability in the headwaters of the Castril river, a normal situation in the headwaters of the Mediterranean rivers, like the central mountains of Spain (System Central) or here in the Subbetic mountains. On the other hand, the absence of the freshwater crayfish (Austropotamobius pallipes) may be an important limitation because crayfishes are an important local resource for otters. They are the main prey item in the next Guardal river during Summer (Gil-Sánchez & Alba Tercedor 1997). However, brown trout availability of the Castril river is sufficient to supplied the freshwater crayfish absence. Although the trouts are no present in the Castril river out the study section (because the increment of water temperature and Castril village pollution), otters are certainly present because of the abundance of ciprinids (Barbus sclateri, Chondostroma polylepis and Leuciscus pyrenaicus) and the red swamp crayfish (Procambarus clarkii).
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Conservation of otter (Lutra lutra) in a Mediterranean area: the importance of habitat quality and temporal variation in water availability

Conservation of otter (Lutra lutra) in a Mediterranean area: the importance of habitat quality and temporal variation in water availability

In southern Spain otters still maintain healthy populations, mostly localised in areas of low human population density (Delibes, 1990). To test the effects both of habitat quality (type and structure of water body, cover, characteristics of the surrounding areas, water pollution and human disturbance) and water availability on otter distribution the following questions were asked: 1) What are the most important differences in habitat features between sites with otters and sites lacking them?; 2) Is there any quantitative relationship between general habitat quality and otter distribution?; 3) Does water availability influence otter distribution? Finally, the probable consequences of the response of otters to water shortage in Mediterranean freshwater habitats were examined.
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Surveillance of habitats and plant diversity indicators across a regional gradient in the Iberian Peninsula

Surveillance of habitats and plant diversity indicators across a regional gradient in the Iberian Peninsula

The Iberian Peninsula is an important reservoir of European biodiversity (Morillo and Gomez-Campo, 2000), and is usually included in theMediterranean Region” hotspot of global biodi- versity (Myers et al., 2000). However, the peninsula also presents challenges for setting up an ecological monitoring program due to its high environmental and social-ecological heterogeneity (Rey-Benayas and Scheiner, 2002; Rescia et al., 2008). Previous assessment and monitoring programmes in Spain and Portugal have ranged from national forest inventories and land cover mapping to landscape inventories from both structural (e.g. Elena- Rosselló et al., 1997, 2005 in Spain; and Caetano et al., 2008, in Portugal) and functional (e.g. Alcaraz-Segura et al., 2009) per- spectives. However, due to their specific goals these approaches have not been able to identify habitat and biodiversity indicators with the enough detail to support regional management needs whilst meeting the requirements of national and international reporting, e.g. on the application of the EU Habitats Directive and the implementation of the Natura 2000 network (Evans, 2006). There is therefore a requirement to test a common Iberian sys- tem for habitat and biodiversity monitoring that can contribute to cross-border management and policy, as well as to international goals.
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Diversity and ecological characteristics of the vascular flora in the Western Mediterranean (Eastern Andalusia, Spain)

Diversity and ecological characteristics of the vascular flora in the Western Mediterranean (Eastern Andalusia, Spain)

With this work, the objective is to analyse and highlight the importance of vascular flora of eastern Andalusia, as it is an exceptional focal point within the hotspot of the Mediterranean Basin, in good part due to its strategic position of bridging the Iberian Peninsula and North Africa at the end of the Miocene. As well as serving as a refuge for the flora of continental Europe during the period of the glaciations (Blanca 1993) and bearing diverse substrates with nutritional imbalances for plants (volcanic, peridotitic, dolomitic, gypsiferous, saline, etc.), giving rise to in a multitude, at the world level, of territories rich in endemic taxa (Johnston 1941; Rivas Goday and Esteve Chueca 1972; Rivas Goday 1973, 1974; Esteve and Varo 1975; Rivas Goday and López González 1979; Kruckerberg 1986, 1992; Cabezudo et al. 1989; Mota et al. 1993, 2008; Cowling et al. 1995; Stevanovič et al. 2003; Reeves and Adigüzel 2004; Safford et al. 2005; Figueroa 2006; Selvi 2007; Fuente et al. 2007; Heads 2008; Lendínez et al. 2011; Mota et al. 2011; García-Barriuso et al. 2012; Pérez-Latorre et al. 2013), as well en dicha flora, que suponen más del 42 % de la flora de la Península Ibérica y el 29,9 % de la flora europea. Un 10,3 % de la flora es endémica (350 táxones), que representan el 34,3 % de los endemismos peninsulares y baleares y el 2,6 % de los de la Cuenca Mediterránea, entre los que se incluyen 6 de los 17 géneros endémicos de la Península Ibérica e Islas Baleares, 3 de ellos exclusivos del territorio analizado. Caméfitos y hemicriptófitos suponen el 45 % de la flora, con valores decrecientes para los terófitos al ascender en altitud (del 41,1 al 8,1 %) y creciente para los hemicriptófitos (del 22,4 al 63,2 %). Un 39,2 % de los táxones son mediterráneos, seguidos por los iberonorteafricanos (15,3 %), los ibéricos (13,9 %) y en quinto lugar los endemismos locales (9,4 %). El 12,5 % de los táxones están amenazados según los criterios de la UICN y de un 5,1 no se tienen datos suficientes. Tanacetum funkii, exclusivo de este área, se considera extinto. Solo 6 familias concentran el 43,5 % de los táxones amenazados. En el termotipo mesomediterráneo (600-1.400 m) se desarrollan el 82,8 % de las especies presentes, con un máximo entre los 700-800 m, y mínimos en el ámbito marino (-100-0 m) y, por el contrario, en las cotas más elevadas (3.300-3.400 m).
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CENSO VISUAL DE NUTRIA (Lutra lutra) Y VISÓN AMERICANO (Mustela vison) EN EL PARQUE NATURAL DE LAS HOCES DEL RÍO DURATÓN (SEGOVIA)

CENSO VISUAL DE NUTRIA (Lutra lutra) Y VISÓN AMERICANO (Mustela vison) EN EL PARQUE NATURAL DE LAS HOCES DEL RÍO DURATÓN (SEGOVIA)

— Los observadores: Como se ha explicado anteriormente, el grueso (20 personas) de los participantes en el censo visual procedían de un campo de trabajo organizado por el Parque Natural. La aceptación de la realización del censo visual de la nutria no fue una condición previa para inscribirse al campo de trabajo, asunto que se propuso in-situ y, tras ser discutido, se decidió por mayoría que el campo de trabajo participaría en esta actividad. Ruiz-Olmo (1995b) encuentra diferencias significativas en la probabilidad de detectar a las nutrias según la experiencia del censador. Además de la falta de experiencia en trabajos de campo de la inmensa mayoría de estos observadores voluntarios, hubo también diversos grados de motivación entre ellos con respecto a la realización del censo visual, variando desde un gran entusiasmo a una cierta apatía por los objetivos del trabajo. Dentro de los menos entusiastas se detectaron fallos puntuales como dormirse en el puesto, abandonarlo para acudir al puesto contiguo, etc. Con no haber sido numerosas esas anomalías, consideramos que han podido tener una influencia sobre los resultados. El análisis comparativo de estos inconvenientes y de la positiva valoración que del censo visual, en su vertiente de educación ambiental, hicieron la mayoría de los participantes, nos lleva a la conclusión de que, si bien resulta constructivo contar con voluntarios en este tipo de trabajos, debe hacerse una selección previa de los participantes.
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Efectos del hábitat y la disponiblidad de presa spbre la dieta y distribución de la nutria (Lutra lutra) en el Parque Natural Sierra Norte de Sevilla

Efectos del hábitat y la disponiblidad de presa spbre la dieta y distribución de la nutria (Lutra lutra) en el Parque Natural Sierra Norte de Sevilla

(Barbus sclateri), the red swamp crayfi sh (Procambarus clarkii) and common frog (Rana perezi) stood out in this order of preference. 61% of preys and 84% of total biomass corresponded to freshwater fi sh individuals. This fact underlines the high importance that freshwater fishes had for the otters´ diet within the study area. However, otter’s diet showed a faithfully pattern in relation to preys availability, since they mainly fed on the most avai- lable preys. This general pattern must be specifi ed, as the otter tended to select or reject some fi sh species and/or fi sh sizes. Long sized fi shes were specially consumed except for the sun fi sh (Lepomis gibbosus) with which this general pattern appeared inverted. In summary we can say that the Sierra Norte´s otter population is in good or very good health.
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SONDEO Y EVOLUCIÓN DE LA DISTRIBUCIÓN DE LA NUTRIA PALEÁRTICA (Lutra lutra LINNAEUS, 1758) EN EL PAÍS VASCO (N ESPAÑA)

SONDEO Y EVOLUCIÓN DE LA DISTRIBUCIÓN DE LA NUTRIA PALEÁRTICA (Lutra lutra LINNAEUS, 1758) EN EL PAÍS VASCO (N ESPAÑA)

b) la vertiente mediterránea, alavesa, donde se aprecia la alternancia de cadenas montañosas y de amplios valles aluviales destinados a cultivos y asentamientos humanos. El clima de la totalidad del área de estudio se caracteriza por su doble in- fluencia atlántica y mediterránea, con sus respectivas franjas de transición. Desde el punto de vista hidrológico, los ríos principales tienen una dirección con doble sentido norte-sur y viceversa, salvo los ríos Ibaizabal y Zadorra, que también presentan dirección este-oeste. En general, son de recorrido relativa- mente corto y caudal fluctuante, lechos duros (rocosos y pedregosos) y con poca profundidad de cauce.
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DIFERENCIAS EN LA OCUPACIÓN POR LA NUTRIA PALEÁRTICA ( Lutra lutra ) DE LAGUNAS Y EMBALSES DE ALTITUD EN EL CENTRO Y NORTE DE LA PENÍNSULA IBÉRICA

DIFERENCIAS EN LA OCUPACIÓN POR LA NUTRIA PALEÁRTICA ( Lutra lutra ) DE LAGUNAS Y EMBALSES DE ALTITUD EN EL CENTRO Y NORTE DE LA PENÍNSULA IBÉRICA

Sin embargo en aquellos ecosistemas lacustres oromediterráneos de Sierra Segundera en los que existen buenas poblaciones de trucha común (Salmo trutta) y bermejuela (Rutilus arcasii) la presencia de nutrias durante los meses que no están congelados (al menos parte) se circunscribe sobre todo a la temporada reproductora de Bufo bufo (Lizana et al. 1995, Morales y Lizana 1997, Morales et al. en prensa); mientras el resto del año apenas si se conocen indicios. En estas semanas de prima- vera la presencia de restos de sapos y ranas en los excrementos de Lutra lutra recogi- dos en la sierra es muy elevada (80 - 95% en porcentaje de presencia).
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RESUMEN. Palabras clave: conducta de marcaje, crías, excrementos, gestación, hembras, Lutra lutra, Nutria. ABSTRACT

RESUMEN. Palabras clave: conducta de marcaje, crías, excrementos, gestación, hembras, Lutra lutra, Nutria. ABSTRACT

Sin embargo, en el momento de salir las crías al exterior, el número de excre- mentos fue similar al del resto de ejemplares no reproductores, en consonancia con lo que ha sido reseñado por diversos autores (Ruiz-Olmo y Gosálbez 1997, Jahrl 1995, Reuther et al. 2002), quienes lo relacionan con el incremento de in- dividuos en el medio y una conducta de marcaje posiblemente no madurada de las crías.

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Trophic ecology in marine ecosystems from the Balearic sea (western Mediterranean)

Trophic ecology in marine ecosystems from the Balearic sea (western Mediterranean)

The diets of the sharks E. spinax and G. melastomus, which were the only species coexisting on the MS, showed both similarities and notable differences. Concerning the similarities, both species had comparatively low to moderate values of natantian crustaceans (8-14%IRI) and high values of teleosts (≈25%IRI). Differences appeared in the relative importance of euphausiids and cephalopods, (Fig. 4.3) which showed an inverse pattern in both species: while cephalopods were the most important prey (64%IRI) and euphausiids only vestigial (1%IRI) for E. spinax , values in G. melastomus were inverted (16 and 43%IRI, respectively). Given that both species showed significant diet overlap, such inverse pattern would be a mechanism to lessen the competition on the MS. In agreement with this, Macpherson (1980) found that the diet overlap between these two species were significant for all size classes and seasons in the western Mediterranean. Both sharks consumed mesopelagic preys typical inhabitants of the Benthic Boundary Layer (BBL) (Angel and Boxshall, 1990) such as myctophids, euphausiids (e.g. Meganycthyphanes norvegica ) and cephalopods (e.g. Histioteuthis spp.). These mesopelagic preys would be caught when the BBL remains close to the bottom, indicating the high dependence of slope demersal elasmobranchs on the pelagic ecosystem (Bizzarro et al ., 2007, Rinewalt et al ., 2007). A high dietary overlap between these two species was also reported in the Cantabrian Sea (Preciado et al ., 2009) but, in contrast with the preference of E. spinax for cephalopods in our samples, that population preyed mainly on euphausiids. On the contrary, high similarities were found in the diet composition of E. spinax analysed in the Ligurian sea (Wurtz and Vacchi 1978). Cephalopods (e.g. Heteroteuthis sp., Histioteuthidae) and myctophids were abundant prey in their stomach contents. Macpherson (1980) also described an increase in the consumption of cephalopods as E. spinax grows, although fishes and euphausiids were still the most important prey.
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Genetic diversity and population structure of the non-native Eastern mosquitofish (Gambusia holbrooki) in Mediterranean streams

Genetic diversity and population structure of the non-native Eastern mosquitofish (Gambusia holbrooki) in Mediterranean streams

Both mosquitofish -G. holbrooki and G. affinis - introductions were supported by governmental health agencies to control mosquito populations as vectors of diseases such as malaria (Meffe et al., 1989). To date, both species have been introduced in more than 50 countries and on all continents but Antarctica (Garc´ıa-Berthou et al., 2005). In Europe, introductions began with a few G. holbrooki individuals introduced in eastern Spain in 1921 (Krumholz, 1948; Navarro- Garc´ıa, 2013). From there, humans introduced the species into Italian watersheds and many other Mediterranean countries (Figure 1.3) (Garc´ıa-Berthou et al., 2005). In 1924, mosquitofish from Italy were introduced to the Transcaucasian regions and from there to areas in the south and center of the former USSR (Sella, 1929). Later, eastern mosquitofish were introduced to other malaric areas of the world, including East Asia and Australia (Ronchetti, 1968). As previously mentioned, due to taxonomic confusion, some of the reports of the presence of G. affinis are actually referring to G. holbrooki and vice-versa. For example, both species were reported to have been introduced in Australia, but apparently now only G. holbrooki is present (Congdon, 1995). Conversely, there is only the presence of G. affinis in New Zealand, and its populations seem to proceed from the populations of Hawaii (Purcell et al., 2012), where the species was previously introduced in 1905 (Stearns, 1983). Some genetic research has been directed towards identifying areas of precedence of individuals introduced everywhere, and the patterns detected broadly agree with historical records (e.g. Grapputo et al., 2006; Vidal et al., 2010). However, there is little precise data regarding putative American source populations, as well as a lack of well-known pathways of introduction in most of areas where the species is invasive.
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The evolution of diversity in the structure and function of artificial organisms

The evolution of diversity in the structure and function of artificial organisms

As a graduate student of Francisco Vico, I have been immersed in the dynamic environment provided by the Grupo de Estudios en Biomimética 1 ; which is affiliated to the larger research group Inteligencia Computacional y análisis de imágenes (grupo de excelencia TIC–163), led by José Muñoz Pérez, who has provided kind and useful support. This great environment has been made possible by my lab mates. I have had the opportunity to share my enthusiasm for science with my fellow Ph.D. students, Gema Martín, Daniel Lobo, and Carlos Sánchez. Also thanks to the people how have helped me in this path, such as Julio Pérez, for his technical support and vitriolic but witty observations; Miguel Carmona, for his exciting personality and conversations; Ellen Pearce, for her support in language skills and the opportunity to teach popular science; Francisco Osuna, for his administrative support and warm personality; and Vicente Canteli, for his artistic support, illuminating conversations, and rare wisdom (as Daniel Lobo put it, very appropriately). I also would like to thank my other colleages along these years, both old an new: David Albarracín, Jose Serrano, Cristóbal Carnero, Fran Moreno, Juan Travesedo, Alejandro Villegas, Salva Burrezo, Antonio Gómez, Samuel Morales and María Jose Casas.
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Habitats and biodiversity of decapod crustaceans in the SE Gulf of California, Mexico

Habitats and biodiversity of decapod crustaceans in the SE Gulf of California, Mexico

(Hendrickx and Wicksten 1987, Wicksten and Hendrickx 1992). Except for the slippery prineeps, which typi­ cally occurs on sandy bottom elose to shore, lobsters and mud-shrimps (Thalassinidea) are scarce. Anomura (20 species in total) ineludes a small series of sized hermit crabs species which feature an unbroken distribution pattern from inside the Bay towards the adja­ cent shelf. crabs are known to be mostIy intertidal, sometimes extending their habitat to the shallow subtidal where rocky bot­ tom and associated fauna and flora (e.g. sponges and coralina) serve as refuges for many species of Petrolisthes, Paehyeheles or Megalobraehiunl. Exelusively subtidal porce­ lain occurring in the Gulf of California inelude the genera Orthochela. Eueeramus, Poreellana, Minyoeerus, Ulloaia and Polyonix, all of them represented at least with one species in the Bay of Mazatlán. The largest group of species is,
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PREDATION UPON THE EUROPEAN RABBIT (ORYCTOLAGUS CUNICULUS) IN MEDITERRANEAN HABITATS OF CHILE AND SPAIN: A COMPARATIVE ANALYSIS

PREDATION UPON THE EUROPEAN RABBIT (ORYCTOLAGUS CUNICULUS) IN MEDITERRANEAN HABITATS OF CHILE AND SPAIN: A COMPARATIVE ANALYSIS

The comparatively smaller size of predators in the Chilean assemblage is correlated with the reduced importance of rabbits as prey in central Chile. This could be determining the overall trend observed in this country. because in Spanish hunting sets the larger predators tend to prey more strongly on rabbits than the smaller ones (Delibes 1980). However, size per se does not seem to be the causal factor underlying low consumption of rabbits by the Chilean predators. In fact, the small percentage importance of rabbits in their diet is associated with smaller size (relatively to Spanish counterparts) in six cases ( Felis guigna, Parabuteo unicinctus, Geranoaetus melanoleucus. Falco sparverius, Bubo virginianus, and Strix rufipes). However, the same holds true in six other cases when they are actually larger (Dusicyon culpaeus, Buteo polvosoma, Circus cinereus, A sio flammeus, A thene cunicularia, and Tyto alba). For the remaining four species there is not enough information on sizes or diet to draw a conclusion.
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Empleo de excrementos de nutria Lutra lutra (Linnaeus, 1758) para la diagnosis específica de los cangrejos de río en la Península Ibérica

Empleo de excrementos de nutria Lutra lutra (Linnaeus, 1758) para la diagnosis específica de los cangrejos de río en la Península Ibérica

La nutria paleártica (Lutra lutra) es un carnívoro semiacuático que se nutre de un amplio espectro de presas potenciales. Su dieta se determina frecuentemente a partir de los fragmentos sin digerir hallados en sus depo- siciones, o de restos corporales sin devorar depositados en las inmediaciones de los tramos que habitan. En la Península Ibérica existen tres especies de cangrejos de río, una de ellas nativa y en franco riesgo de desaparición, las otras dos proceden de Norteamérica y tienen carácter invasor. En ambientes de montaña mediterránea, donde es frecuente la desecación total o parcial de numerosos arroyos y barrancos, los cangrejos se convierten a menudo en presas importantes para las nutrias. Sin embargo, en muchos de los trabajos relacionados con la ecología trófica de la nutria no se hace referencia a la especie de cangrejo implicada. En el presente estudio se definen varios rasgos morfológicos de cangrejos hallados en excrementos y restos sin consumir de nutrias del Sistema Ibérico Sur, que permiten la determinación de la especie de una manera rápida y sencilla. Se propone aprovechar estos caracteres para localizar e identificar poblaciones de cangrejos durante la realización de son- deos de nutria, y viceversa.
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Trophic relationships in orchid mycorrhiza – diversity and implications for conservation

Trophic relationships in orchid mycorrhiza – diversity and implications for conservation

In terms of preserving an orchid species, this means that fungi employed during germination cannot be disregarded. All orchids are to some degree mycoheterotrophic, although this designa- tion has somewhat misleadingly been restricted to species with obviously chlorophyll-deficient adult stages. The sequential or simultaneous combina- tion of mycotrophy and phototrophy, that is char- actistic of orchids, may be described as mixotro- phy. The only exception from mixotrophy would be the entirely mycotrophic orchids. Cephalanthera damasonium is an example of a species that segregates into holomycotrophic and mixotrophic individuals: the albinos showed no trace of photoassimilation as adult plants, whereas the adult green individuals were found to be mixotrophic with about fifty-fifty contribution of carbon from either system (Julou et al. 2005). Other studies, also based on the distribution of sta- ble carbon and nitrogen isotopes, indicate that green leaved forms may aquire a significant frac- tion of their C and N through fungi, but that species differ considerably in this respect (Gebauer & Meyer, 2003). Thus orchids are arranged in a continuum from holomycotrophy to various degrees of mixotrophy.
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Dieta otoño-invernal de tres carnívoros, visón europeo (Mustela lutreola), nutria euroasiática (Lutra lutra)

Dieta otoño-invernal de tres carnívoros, visón europeo (Mustela lutreola), nutria euroasiática (Lutra lutra)

Dieta otoño–invernal de tres carnívoros, visón europeo (Mustela lutreola), nutria euroasiática (Lutra lutra) y gineta común (Genetta genetta), en el norte de España.— Se describe la dieta otoño–invernal de tres carnívoros (Mustela lutreola, Lutra lutra y Genetta genetta) en el norte de España. La dieta fue analizada a partir de 85 muestras de visón europeo, 156 de nutria euroasiática y 564 de gineta común. El visón europeo basó su dieta en micromamíferos (38,1% de frecuencia relativa), peces (30,9%) y aves (16,7%). La gineta común consumió principalmente micromamíferos, aves y frutos, mientras la nutria predó casi exclusivamente peces (95%). Los índices de Levins de la anchura del nicho trófico del visón europeo, la gineta común y la nutria fueron 3,76, 3,77 y 1,10 respectivamente. Los solapamientos del nicho trófico durante otoño–invierno del visón europeo (índice de Pianka) respecto a la gineta común y la nutria euroasiática fueron 0,77 y 0,60, respectivamente. El tamaño medio de las truchas consumidas por las nutrias fue mayor que el de las con- sumidas por el visón europeo.
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Habitat selection in land by the marine otter, Lutra felina, at Pan de Azúcar lsland, Chile

Habitat selection in land by the marine otter, Lutra felina, at Pan de Azúcar lsland, Chile

De igual modo, los dos sitios señalados como madrigueras en este estudio, coinciden con sitios compuestos por rocas de gran tamaño.. Otros factores como la abundancia[r]

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NUEVOS DATOS SOBRE LA DISTRIBUCIÓN Y DIETA DE LA NUTRIA PALEÁRTICA (LUTRA LUTRA) EN LA PROVINCIA DE SALAMANCA

NUEVOS DATOS SOBRE LA DISTRIBUCIÓN Y DIETA DE LA NUTRIA PALEÁRTICA (LUTRA LUTRA) EN LA PROVINCIA DE SALAMANCA

recovery of the Eurasian otter in the province of Salamanca, occurring in 39% of the sites surveyed in the decade of the 80`s, 64% in the 90^s and 74% of the sites in 2005. The number of positive sites reveals a widespread distribution, the otter being present in nearly all the river basins of the province of Salamanca. The number of positive surveys is higher in the western area (regions of El Abadengo, Campo Charro and Arribes del Duero), whereas in the northeastern cultivated areas it is rare with a seasonal presence, and restricted to reservoirs. The diet of the otter in Salamanca is based preferentially on fish and varies in function of avail- abity. Amphibians and aquatic reptiles, such as water snakes are secondary prey, whilst birds, mammals and invertebrates are accesory prey.
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