Search

Detection probability is an important input when studying and managing species. It reduces the miscalculations of the estimates of occupancy, population abundances and their trends inherent to the imperfect detection during sampling. However, detection probability may vary in relation to environmental and biological factors, such as the presence of other species of similar ecological niche. We used a two-species single-season occupancy model to analyse the detection probability of the native Eurasian otter Lutra lutra and the invasive American mink Neovison vison in the northeast of the Iberian Peninsula and to test for potential differences in their detection when co-occurring and when not. Despite the known behavioural change of American mink towards a more terrestrial diet and a more diurnal activity pattern in the presence of Eurasian otter, their detectability did not vary when both species co-occurred versus when they did not. However, we observed seasonal differences in the probability of detection. Specifically, the probability of detection was higher in winter for both species. Furthermore, Eurasian otter was more often detected in sites with clay substrate, whereas American mink in sites with clay and rocks. These results indicate that the effectiveness of monitoring of Eurasian otter and American mink remains independent of the species co-occurrence. Yet, seasonal variations in the detection should be taken into account when monitoring.

53 pages, 10 figures, 20 tables, This paper provides an overview of the last 40 years of use, and in many cases abuse, of the natural resources in Catalonia, a country that is representative of European countries in general, and especially those in the Mediterranean region. It analyses the use of natural resources made by mining, agriculture, livestock, logging, fishing, nature tourism, and energy production and consumption. This use results in an ecological footprint, i.e., the productive land and sea surface required to generate the consumed resources and absorb the resulting waste, which is about seven times the amount available, a very high number but very similar to other European countries. This overexploitation of natural resources has a huge impact on land and its different forms of cover, air, and water. For the last 25 years, forests and urban areas have each gained almost 3% more of the territory at the expense of agricultural land; those municipalities bordering the sea have increased their number of inhabitants and activity, and although they only occupy 6.7% of the total surface area, they account for 43.3% of the population; air quality has stabilized since the turn of the century, and there has been some improvement in the state of aquatic ecosystems, but still only 36% are in good condition, while the remainder have suffered morphological changes and different forms of nonpoint source pollution; meanwhile the biodiversity of flora and fauna remains still under threat. Environmental policies do not go far enough so there is a need for revision of the legislation related to environmental impact and the protection of natural areas, flora, and fauna. The promotion of environmental research must be accompanied by environmental education to foster a society which is more knowledgeable, has more control and influence over the decisions that deeply affect it. Indeed, nature conservation goes hand in hand with other social and economic challenges that require a more sustainable vision. Today’s problems with nature derive from the current economic model, which is environmentally unsustainable in that it does not take into account environmental impacts. Lastly, we propose a series of reasonable and feasible priority measures and actions related to each use made of the country’s natural resources, to the impacts they have had, and to their management, in the hope that these can contribute to improving the conservation and management of the environment and biodiversity and move towards sustainability, This research was funded by the Institut d’Estudis Catalans (IEC). With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

Simple Summary Invasive species are widely recognized to negatively affect native species through both direct and indirect interactions. When diet overlap between the native and invasive species increases, their competitive interaction is expected to increase too. This in turn may lead to displacement of one of the species. However, the specific mechanisms of the diet displacement are still unclear. In this study, we analysed the diet and diet overlap between the critically endangered European mink and the invasive American mink during the invasion process of the latter species by means of stable isotope analyses. We found a significant diet overlap between the native and invasive mink when they co-occur, an important individual variation of diet, and no significant change of diet of the native species in response to the arrival of the invasive mink. These results suggest significant competitive pressure imposed on the native European mink by the invasive American mink. As such, urgent implementation of control measures of invasive species is needed to ensure the viability and conservation of endangered European mink populations. Abstract The pressure elicited by invasive species on native species significantly increases with the increase of the overlap of their ecological niches. Still, the specific mechanisms of the trophic displacement of native species during the invasion process are unclear. The effects of the invasive American mink (Neovison vison) on the critically endangered European mink (Mustela lutreola) was assessed by analyses of diet and niche overlap during the invasion process. To do this, the isotopic composition (δ13C and δ15N) of both species of mink and their four main types of prey was analysed. Significant trophic overlap between the native European mink and invasive American mink was found when they coexisted in sympatry. Furthermore, both mink species were characterised by significant individual variation in diet and no obvious change in diet of the native species in response to the arrival of the introduced species was observed. High niche overlap registered between both species in sympatry with no displacement in diet of the native mink in response to the arrival of the invasive mink is expected to have important consequences for the viability and conservation of the native mink populations, as it suggests high competitive pressure.

espanolLa actualizacion de los datos sobre distribucion y frecuencia del desman (Galemys pyrenaicus) en Cataluna y Andorra muestra una regresion reciente importante en ambos territorios de los Pirineos en los que esta especie tiene su limite nororiental de distribucion. Esta informacion se ha obtenido, tras la prospeccion repetida de indicios de desman en 420 tramos fluviales en los periodos 2000-2003 y 2013-2107. La regresion se refleja en la frecuencia relativa de la especie y afecta a todas las cuencas fluviales, con disminuciones de tramos con resultado positivo del 43% en Cataluna y del 70% en Andorra. Tambien se observa una extincion local aparente en varios cursos fluviales, en la mayor parte de los cuales el desman tenia una presencia importante en 2000-2003. Se desconocen las causas de esta regresion general, aunque se supone que no existe una causa unica y que ha sido consecuencia de la suma de varios factores de escala local. Entre los factores que pueden haber incidido se citan la fragmentacion del area, los cambios en la gestion de las centrales hidroelectricas, el incremento de la demanda de agua en los valles pirenaicos, las obras publicas en el entorno fluvial y episodios de crecidas catastroficas. Un factor que quiza tambien haya infuido en la regresion es la recolonizacion reciente de la nutria (Lutra lutra) de los rios con desman, lo que podria haber generado una depredacion poco tolerable sobre poblaciones pequenas. Por el contrario, no parece que haya influido el cambio climatico, ya que el desman se mantiene bien en rios del limite meridional con condiciones climaticas potencialmente menos adecuadas. A consecuencia de esta regresion reciente, aplicando los criterios de la IUCN, el desman se deberia de considerar una especie amenazada en la zona de estudio, con las categorias EN (En Peligro) en Cataluna y CR (En Peligro Critico) en Andorra. EnglishThe update of the data about distribution and frequency of the desman (Galemys pyrenaicus) in Catalonia and Andorra –on its northeastern distribution limit- shows a recent and very important regression of this species. This information has been obtained with the monitoring of the desman in 420 river sections in the periods 2000-2003 and 2013-2107. The regression is mainly reflected in the relative frequency of the species and affects all the river basins, with a decrease in the positive points percentages of 43% in Catalonia and 70% in Andorra. An apparent local extinction is also observed in several river courses, in most of which the desman had an important presence in 2000-2003. The causes of this general regression are unknown, although it is assumed that there is no single cause and that it has been the result of the addition of several local factors. The factors that may have affected are the historical fragmentation of the populations, changes in the management of hydroelectric power plants, the increase in water demand in the Pyrenean valleys, public works in the rivers and some episodes of catastrophic floods. A factor that may have also contributed to the regression is the recent recolonization of the otter (Lutra lutra) in rivers with desmans, which could have generated a dangerous depredation over small and fragile populations. On the contrary, climate change does not seem to have influenced, since the desman does not show a negative trend in rivers of the southern limit with less suitable climatic conditions. As a consequence of this recent regression, applying the criteria of the IUCN, the desman must be considered a threatened species in the study area, with the categories EN-Endangered in Catalonia and CR-Critically Endangered in Andorra.

When a population shows a marked morphological change, it is important to know whether that population is genetically distinct; if it is not, the novel trait could correspond to an adaptation that might be of great ecological interest. Here, we studied a subspecies of water shrew, Neomys fodiens niethammeri, which is found in a narrow strip of the northern Iberian Peninsula. This subspecies presents an abrupt increase in skull size when compared to the rest of the Eurasian population, which has led to the suggestion that it is actually a different species. Skulls obtained from owl pellets collected over the last 50 years allowed us to perform a morphometric analysis in addition to an extensive multilocus analysis based on short intron fragments successfully amplified from these degraded samples. Interestingly, no genetic divergence was detected using either mitochondrial or nuclear data. Additionally, an allele frequency analysis revealed no significant genetic differentiation. The absence of genetic divergence and differentiation revealed here indicate that the large form of N. fodiens does not correspond to a different species and instead represents an extreme case of size increase, of possible adaptive value, which deserves further investigation.

The Pyrenean desman (Galemys pyrenaicus) is a small semi-aquatic mammal endemic to the Iberian Peninsula. The species has recently experienced a strong decline and some of its populations are severely threatened with extinction. To help in the preservation of this species, it is critical to understand its genetic structure and main evolutionary units, as these may have specific local adaptations and could be of great conservation value. Sequencing reduced representation libraries (ddRAD) from 26 specimens selected from across its entire range, we obtained around 45,000 loci per specimen and 1185 single nucleotide polymorphisms. Heterozygosity varied substantially among individuals from different areas. Interestingly, specimens from the southeastern Pyrenees had some of the lowest proportions of heterozygous positions inferred from genome-wide data in mammals so far. In addition, we estimated a tree reflecting genomic divergence, performed a principal component analysis, and carried out a Bayesian analysis of the population structure. Combined evidence supported the existence of five distinct genomic clusters largely coincident with the main mountain ranges where the species occurs, with few specimens presenting relevant admixture levels. There was good correspondence between these populations and the mitochondrial lineages detected in a previous study, yet substantial differences in some areas demonstrate the importance of performing genomic analysis to reveal the whole population history. Although the analysis of further specimens is necessary to better characterize the distribution of the different evolutionary units, the distinctive geographical structure of this species revealed by the genomic data should be considered in future conservation plans., This work was financially supported by research Projects CGL2011-22640 and CGL2014-53968-P of the “Plan Nacional I + D+I del Ministerio de Economía y Competitividad” (Spain) to J.C. with contribution of project 014/2008 of the “Convocatoria de ayudas a proyectos de investigación en la Red de Parques Nacionales” (Spain) to J.G. M.Q. was supported by fellowship BES-2012-057135 of the Ministerio de Economía y Competitividad (Spain).

An understanding of population dynamics, especially in endangered species that present metapopulation structures, such Arvicola sapidus, is important to gain knowledge of the dispersal and patterns of both occupation and space use. Here, we use radio tracking to report for the first time the relationship of the southern water vole with the environment in a Mediterranean mountain riparian area and also the relationships between individuals. Along the Montsant River, the size of the home ranges, the average distance travelled daily, the population density and the habitat quality were contrasted. In the subsection with better quality habitat, both the home ranges and distances travelled were smaller than in the subsection with poorer quality habitat, whilst population density was higher in the subsection with better quality habitat. Interactions (static and dynamic) between individuals reflected low sociality, especially between members of different groups. Within a group, adult males did not interact, but interactions between male and female adults intensified during the reproductive period. The home ranges of individuals changed with the emergence of new available gaps and in response to reproduction needs. Tracking a dispersant young male showed a trajectory in stages and made obvious the high risk of predation during this period. Our results here, and previously, indicate the possible effect of habitat quality on space use and relationships between individuals, emphasising the importance of the quality and structure of habitat in the conservation of the southern water vole.

Resumen El conocimiento de las alternancias entre actividad/descanso durante ciclos de 24 h es importante para comprender la forma en que las especies interaccionan con el medio y, a la vez, puede proporcionar herramientas para desarrollar medidas de conservacion adecuadas. El conocimiento sobre esta alternancia de actividad y reposo es escaso en la rata de agua Arvicola sapidus, un roedor endemico de la peninsula Iberica y Francia. El presente estudio tiene como objetivo contribuir al conocimiento de los patrones de actividad/reposo hora a hora, mediante la cuantificacion de las distancias recorridas (asociadas a actividad) para diferentes individuos de Arvicola sapidus en un tramo del rio Montsant, utilizando la tecnica del radioseguimiento. Los resultados han mostrado que la rata de agua se comporta como una especie catemeral. La aproximacion al patron de actividad obtenida mediante datos sobre la frecuencia de actividad en intervalos de una hora mostro una menor resolucion que la aproximacion obtenida a partir de las distancias medias recorridas en intervalos de una hora. Los individuos que ocupaban un habitat suboptimo recorrieron una distancia media por hora mayor que la de los individuos que ocupaban un habitat optimo. La actividad se ha relacionado con las condiciones de habitat. Estas consideraciones ayudarian a explicar por que la fragmentacion y destruccion del habitat se configuran como las principales causas de regresion de la rata de agua, asi como la importancia de la conservacion del habitat para favorecer el mantenimiento de la especie. Palabras-clave: actividad, Arvicola sapidus, distancias recorridas, habitat, radioseguimiento. Abstract Knowledge of the alternation between activity and rest during the 24 h daily cycle is important in order to understand how species interact with the environment and can also provide tools for designing appropriate conservation measures. At present, little is known about this alternation in Arvicola sapidus, an endemic rodent restricted to the Iberian Peninsula and France. This study aims to extend our knowledge of this rodent’s hour to hour activity/rest patterns by using radiotelemetry to quantify the distances travelled (associated with activity) by individual southern water voles along a stretch of the Montsant River. The results showed that the southern water vole’s behaviour is cathemeral. The use of data of frequency of activity in one-hour intervals to assess the activity pattern showed a lower resolution than the use of data of the mean distances travelled in one-hour intervals. The individuals occupying a suboptimal habitat travelled a greater mean distance per hour than individuals occupying an optimal habitat, indicating that their activity was related to the habitat conditions. These considerations may help to explain why fragmentation and habitat destruction are emerging as the main cause of the decline of the southern water vole, and underline the importance of habitat conservation to encourage the maintenance of the species. Key words: activity, Arvicola sapidus, distances travelled, habitat, radiotelemetry. DOI: 10.7325/Galemys.2015.A5

Resumen Se han estudiado los cambios en la distribucion y frecuencia de los micromamiferos semiacuaticos, entre los anos 2000 y 2013-2014, de la red fluvial del parque natural Alt Pirineu, en los Pirineos meridionales. La especie prioritaria del estudio ha sido el desman iberico (Galemys pyrenaicus), pero tambien se han evaluado las frecuencias de los musganos (Neomys fodiens y Neomys milleri) y la rata de agua (Arvicola sapidus), para las que los datos del ano 2000 eran parciales. Es la primera vez que se realiza un estudio diacronico sobre la frecuencia relativa del desman a escala regional y aplicando un metodo identico en los dos muestreos. La metodologia utilizada ha sido la deteccion de indicios de presencia de estas especies en 66 tramos fluviales, prospectados en los dos periodos considerados. Actualmente, los micromamiferos mas comunes son los musganos, presentes en casi todos los tramos (94%), seguidos del desman (45%) y de la rata de agua (34%). Se ha constatado que el desman presenta una regresion intensa en una subcuenca fluvial (Noguera de Cardos) y ha desaparecido en su cabecera. Esta regresion parece atribuible a cambios recientes en la gestion hidroelectrica y se ha iniciado un seguimiento para evaluar esta hipotesis. Palabras clave: Arvicola, Galemys, mamiferos semiacuaticos, Neomys, seguimiento. Abstract We have studied the changes in the distribution and frequency of semiaquatic micromammals in the river network of Alt Pirineu Natural Park (southern Pyrenees, Iberian Peninsula) between 2000 and 2013-2014. The priority of this work has been the Iberian Desman (Galemys pyrenaicus) but we also evaluated the frequency in Water Shrews (Neomys fodiens and Neomys milleri) and Southern Water Vole (Arvicola sapidus), for which 2000 data were incomplete. It is the first time that a diachronic study on the relative frequency of Iberian Desman takes place at regional level and using an identical method in the two surveys. The methodology was the detection of faeces of these species in 66 river sections, prospected in the two periods considered. The most common semiaquatic mammals were Water Shrews, present in almost all river sections (94%), followed by the Desman (45%) and the Water Vole (34%). We found an intense regression of the Desman in a river basin where this species was common in 2000 (Noguera de Cardos) and it is extinct in the upper basin of this river. This local regression is probably attributable to a recent change in the model of hydroelectric management and we started a survey to evaluate this hypotesis. Keywords: Arvicola, Galemys, Neomys, semiaquatic mammals, survey. DOI: 10.7325/Galemys.2015.A4

The genetic characteristics of introduced populations have a relevant impact on their ability to establish and spread. The American mink (Neovison vison), native to North America, is an important invasive species in the Iberian Peninsula. Here, we used mitochondrial DNA sequences data to investigate the genetic diversity and phylogeographic structure of invasive versus native populations of this species. We also evaluated whether genetic diversity in invasive populations could be explained by the genetic characteristics of the native sources from which they derived. Phylogenetic analysis revealed two major lineages in the native range, which indicated a clear separation between western and eastern populations. On the contrary, we found no evidence of genetic structure in the invasive range. This was probably the result of the diverse origins of the released specimens and the rapid expansion and encounters of the introduced populations. We detected spatial mixing of both North American lineages in several sampling localities of the north central area of the Iberian Peninsula, giving rise to high levels of genetic diversity in some areas compared to North American populations. This could potentially lead to higher fitness of these individuals and thus increase the population viability and invasiveness of this species. These results point to the need to better study the populations in which lineages mix and, if necessary, intensify control efforts in them.

The ongoing academization of gastronomic studies indicates the necessity for a commonly accepted classification system for cooks that does not contradict scientific approaches. This work discusses the fundamentals used by chefs and scientists to classify unelaborated food products; proposes taxonomic gastronomy as a new interdisciplinary framework that studies the taxonomy surrounding gastronomy; and presents a categorization of unelaborated food products that follows commonly accepted culinary criteria yet avoids contradiction by scientific knowledge. As little literature focuses on these issues, and similar experiences are scarce, it is concluded that further cross-disciplinary endeavors such as this will continue to be greatly fruitful., This work was carried out in the framework of the agreement between the Universitat de Barcelona and elBulliFoundation signed on 23 October 2012 and was subsidized by the Catalan government (grant number 2009SGR0403, 2014SGR1241, 2014SGR7, 2014SGR514, 2014SGR1315, 2014SGR1208, 2014SGR1480 and 2014SGR623).

For the recovery and conservation of endangered species such as the southern water vole Arvicola sapidus, it is important to understand the effects of predation on their populations. The impact of a predator on a prey species depends on the dynamics and structure of their populations, the abundance of both species and their relationships with other species. When considering broad geographic areas, the analysis of the trophic dimension can provide an estimate of the effect of predatory pressure on the prey. To determine the potential impact of predators on the southern water vole, we used information provided in 74 studies concerning the diet of predators in the geographical range of the prey species. The trophic spectrum was determined based on faeces, stomach contents or pellets in which the arvicoline was present. Based on the percentage of biomass consumed in each of nine trophic categories, the potential impact posed by predators was linked with dietary profile, trophic diversity, intensity of southern water vole consumption and availability of preferred prey. In the localities studied, southern water voles are not the preferred prey of any of the predators we considered, but represent an alternative prey for some of them, especially when their main prey species are scarce. The predators with the greatest potential impact on southern water vole populations are Lutra lutra and Ardea cinerea; those with a moderate impact are some mesocarnivores (Felis silvestris, Genetta genetta, Neovison vison, Vulpes vulpes and Martes foina), a bird frequenting aquatic environments (Ciconia ciconia), and the raptors Aquila fasciatus and Hieraaetus pennatus. The results obtained may be useful in the planning of measures for the conservation of the southern water vole, such as translocations or reintroductions, and in the design of strategies to reduce predatory pressure with the aim of promoting the success of these programmes.

Understanding changes over time in the distribution of interacting native and invasive species that may be symptomatic of competitive exclusion is critical to identify the need for and effectiveness of management interventions. Occupancy models greatly increase the robustness of inference that can be made from presence/absence data when species are imperfectly detected, and recent novel developments allow for the quantification of the strength of interaction between pairs of species. We used a two-species multi-season occupancy model to quantify the impact of the invasive American mink on the native European mink in Spain through the analysis of their co-occurrence pattern over twelve years (2000–2011) in the entire Spanish range of European mink distribution, where both species were detected by live trapping but American mink were culled. We detected a negative temporal trend in the rate of occupancy of European mink and a simultaneous positive trend in the occupancy of American mink. The species co-occurred less often than expected and the native mink was more likely to become extinct from sites occupied by the invasive species. Removal of American mink resulted in a high probability of local extinction where it co-occurred with the endemic mink, but the overall increase in the probability of occupancy over the last decade indicates that the ongoing management is failing to halt its spread. More intensive culling effort where both species co-exist as well as in adjacent areas where the invasive American mink is found at high densities is required in order to stop the decline of European mink.

The Pyrenean desman is considered a flagship species for biodiversity and evolution. However, its scientific knowledge is still under development and currently on debate, particularly in relation to its behavioural ecology and social organization. Based on the previous hypothesis of individual desmans being solitary and territorial, activity and space patterns were considered to be arranged to avoid conspecifics. However, recent insights into the species’ social behaviour revealed non-interspecific avoidance. With this study, we provide novel insights into the activity and space patterns of the desman, and their relation to its social behaviour. A total of 30 individuals were trapped, 18 of which provided informative radiotracking data to study (1) activity behaviour, (2) the proportion of the home range utilized and the distances travelled, and (3) the dominant movement directionality. Activity and space use patterns were affected by daylight and seasonality, but not by sex, age or number of other conspecifics sharing the home range. In contrast to the previous observations, individuals did not show a pattern of directionality in their movements. Noticeably, we observed encounters between individuals without evidence of aggressive behaviour. Our results suggest that desmans do not alter their activity or their spatial behaviour to avoid encounters with conspecifics, as previously suggested. These novel findings provide more evidence of a social structure and organization with social interactions and non-aggressive behaviour. This is of relevance for management actions and for the conservation of this endemic mammal.

Predator control has historically shaped management towards minimising predator pressure on sensitive species in most hunting and protected areas. Despite widespread use, few studies of medium-sized carnivores have evaluated such control. To fill this void, we studied the effect of control on shaping a carnivore community consisting of European badgers Meles meles Linnaeus, 1758, stone martens Martes foina Erxleben, 1777 and red foxes Vulpes vulpes Linnaeus, 1758, in the Serra de Montsant area (NE Spain), and we report the recovery dynamics for different habitats (forest, scrubland and cultivated land) over time (3 years) when that control was halted. The results show that non-selective predator control is inadequate to reconcile the conservation of ecosystems with hunting. Specifically, it favours the frequency of occurrence of red foxes, which are the main consumer of small game species, and also reduces the frequency of occurrence of European badgers and stone martens, which are protected speci...

To promote management and conservation, it is useful to identify the factors that determine species distribution and to understand the mechanisms that regulate the organization of species assemblages or influence the dynamics of communities. Using information provided by 842 camera-trap photos and 8175 scats, we studied the factors that favour the coexistence of European badgers (Meles meles), red foxes (Vulpes vulpes) and stone martens (Martes foina) in a Mediterranean, agroforestry environment in the Iberian Peninsula. With extensive, simultaneous occupation of the space, and simultaneous activity during a broad time period (basically nocturnal and crepuscular activity patterns), the carnivores displayed different strategies depending on the availability of resources. In summer when plant resources were abundant and easy to access, there was a high overlap in patterns of diet and activity, and the temporal avoidance of the superior competitor allowed joint use of the same plots. In autumn, when there were fewer resources (although still sufficient) that were harder to access, the maintenance of food overlap was compensated for by avoidance and a reduction in overlapping activity. In winter and spring, the differentiation in response behaviour was evident in the partial substitution of plant resources. Differentiation in niche dimensions has been linked to complementarity, the differential needs and capacities of each species, and their biology. Differentiation in response behaviour was compatible with the hierarchical structure of the carnivores: European badger; red fox; stone marten. Knowledge of these factors and mechanisms increases our understanding and can help in the prediction of responses to disturbances. Consequently, it helps to improve management and conservation actions.

The American mink Neovison vison is an elusive mustelid that is monitored mostly through the detection of its field signs, namely, footprints and scats. In Europe, the American mink has been often monitored using the standard otter survey strategy developed specifically for the Eurasian otter Lutra lutra, requiring to walk transects of 600 m spaced at least 5 km apart. We tested whether the standard otter survey strategy was appropriate for surveying mink. We studied a high-density population of mink along a 9-km stretch of river between December 2004 and April 2005. Monthly surveys were conducted and scats and footprints were recorded within 100-m sections along the river. The results showed a monthly variation in signs recovery, with the months of December, January and February being the best ones for surveying. Transects of 600 m detected mink between 74 and 90 % of the times in all months, excluding March when detection was as low as 56 %. Taken all together, the results suggest that the standard otter survey strategy was adequate to detect mink, at least in this case where species density was high. The study also highlighted monthly differences in signs detection, suggesting that temporal variations should be taken into account when designing the sampling strategy and the length of the sampling units (transects). In the months immediately following the mating season (and possibly in lower-density mink populations), it may be advisable to increase the length of transects to increase detection of mink.

We studied the morphology of American mink Neovison vison in five out of the six introduced populations in Spain. The spatial and temporal variation of body weight (BW), body length (BL), tail length, hind-foot length and ear length were analysed. Temporal trends in BW and BL in relation to years since mink introduction were also analyzed. In addition, we tested the effect of sex, age (juvenile, subadult and adult) and age–sex interaction, on each parameter. Morphological parameters differed between populations, illustrating the high variability of body size of American mink in different environments, and the phenotypic plasticity of the species. Annual variations were synchronized between populations, suggesting a large-scale effect on all of them. BW and BL showed a decreasing trend in both males and females in relation to years since introduction. This decrease may be related to mink's diet. Differences in sex and age were found, pointing to sexual dimorphism in adults, subadults and juveniles. The dimorphism in non-adult individuals suggests that subadult males may have a competitive advantage from subadult females in feeding and/or hunting on bigger prey from an early age (resource partitioning hypothesis).

The Southern water vole, Arvicola sapidus, is endemic to the Iberian Peninsula and France. Despite being catalogued as vulnerable, our current knowledge of this species is not sufficient to establish measures for its conservation and recovery, particularly in riparian zones of Mediterranean mountain areas. The aim of this study was to identify factors related to habitat configuration that determine the presence or absence of the species in the Montsant River. Specifically, we associated the presence/absence of this arvicolid rodent with composition of vegetation, river bank morphology, and watercourse characteristics. The results suggest that, in this area, the most favorable places for the species are those with a high degree of cover of herbaceous plants (mainly helophytes) and moderate to low levels of tree and shrub cover; gently sloping banks and a soft substrate; and the presence of water, with moderate to high stream widths and depths. In addition, we developed a classification method which allowed us to classify and characterize habitat conditions: the optimal scenario (preferential for arvicoline establishment), the suboptimal scenario (whose use is related to opportunities to find best scenarios), and the hostile scenario (not acceptable for use). In such riparian areas, the results revealed that the Southern water vole is a specialist in terms of habitat selection, but behaves as a generalist in terms of occupancy. Its ability to adapt to suboptimal conditions widens the options for managing Southern water vole populations, and indicates that the maintenance and rehabilitation of habitat along continuous stretches of river is the most effective approach to achieving self-sustaining populations.

Loss of biodiversity due to biological invasions is one of the most critical issues our society is facing. American mink is one of the most nefarious invasive non-native species and has major consequences for diversity, ecosystems and economics. A project to evaluate the impact of American mink has been carried out in Catalonia since 2000 under the aegis of regional and national government and a European LIFE programme. In this study, we tested whether temporal variations in the relative abundance of native species were related to American mink. In addition, we compared the abundance of natives before and after mink arrival. Among the competitors spotted genet and European polecat, mink abundance and arrival had a significant negative effect on their populations. However, among black rat and fish prey only three native fish species had a negative temporal relation with the abundance of mink and three fish species showed a significant difference in their abundance before and after mink arrival. The effect of mink was significant among species with a higher niche overlap (polecat and genet versus mink). The persistence and coexistence of the alien and native species seems to depend on heterogeneity, in terms of the based on niche segregation among these species.

The traditional way to deal with hunting interests is often focused on predator control. This approach requires a detailed understanding of predator responses to game management. Control methods can be non-selective and, consequently, can potentially have a negative impact on non-target predator species, affecting carnivore guild. In order to assess the potential risks associated with non-selective predator control in the presence of intraguild competition, the classical Lotka–Volterra competition model was used, but with two additional factors: a linear factor for capture mortality (mortality caused by predator control) and a factor for vacated niche occupancy associated with immigration. Simulation in a scenario with three species revealed that one of them, the red fox Vulpes vulpes, which presented the highest intrinsic growth rate, can show population increases even under moderate control, whereas the population of European badger Meles meles, with a lower intrinsic growth rate, was reduced and, in some cases, may even become extinct. Lastly, the stone marten Martes foina presented a differential response, depending on the removal intensity and strategy employed. This behaviour is compatible with the results observed in a Mediterranean environment subjected to two types of game management: non-selective predator control (culling) and no control. In areas with non-selective control and moderate predator removal, the red fox population remained stable, while the stone marten and the European badger populations reduced markedly or disappeared.

We describe novel aspects of the social organisation of the Pyrenean desman, Galemys pyrenaicus, by studying home range and shelter use behaviour in a local population. A total of 45 individuals were trapped of which 20 provided informative radiotracking data. In contrast to the currently accepted hypothesis [Stone RD. The social organization of the Pyrenean desman (Galemys pyrenaicus) as revealed by radiotelemetry. J Zool 212:117–129; 1987b; Stone RD, Gorman ML. Social organization of the European mole (Talpa europaea) and the Pyrenean desman (Galemys pyrenaicus). Mammal Rev 15 (1):35–42; 1985] individuals were not strictly territorial. Notably, there was no aggression between conspecifics, with simultaneous use of resting sites (shelters used for more than one hour). Resting sites were not permanent or exclusive for any individual. Individuals shared resting sites simultaneously, regardless of sex or age. Our observations recall for a new evaluation of the social structure and organisation of this species based on the new evidence that reveals higher frequency of social interactions than previously described. Resting sites may play an important role in the social organisation of the species, for instance by allowing direct and indirect communicative interactions among neighbouring individuals. This finding is of significance for the management (e.g. census and population monitoring) and conservation (e.g. habitat suitability to allow social interactions) of this endemic and seriously threatened unique mammal.

The effectiveness of culling campaigns to eradicate or limit populations of the alien, invasive American mink in Catalonia was studied by comparing the annual relative abundance of culled versus non-culled populations. We selected three populations that were culled under government campaigns and a fourth that served as a control and hence was left undisturbed (not culled). The study took place between 2002 and 2006 and annual relative abundances were estimated from trapping with bankside traps. The abundance of all four populations remained relatively stable throughout the study period. However, the annual relative abundance of the culled populations was lower than that of the non-culled population, which indicates that culling may have lowered the densities of mink, although eradication was not achieved. We also determined the potential distribution of the American mink in Catalonia by means of a habitat suitability model. The final aim was to assist in planning this species’ management. Almost all watercourses in Catalonia were identified as suitable for the American mink, with preferred areas located in the northeast. We recommend that the government and administrations promote culling campaigns focused on limiting the spread of the American mink as eradication is likely to be difficult to be achieved under the current situation. Target areas should be located on the edges of the American mink’s range and should be prioritized to limit the spread of this species to areas in which there are endangered native species.

Space use, intra-territorial habitat preferences, and factors affecting both were studied in an invading population of American mink, Mustela vison, in two rivers of a Mediterranean region of Spain. Average linear home range was 1.19 ± 0.73 km (±SD) and core area was 0.21 ± 0.08 km for resident males (n = 10); while for females (n =5) they were 0.54 ± 0.14 and 0.19 ± 0.11 km, respectively. Overlapping between the home ranges of residents was low. In no case their core areas overlapped. Home ranges were small in comparison to other study areas and in general the resident minks were territorial. Linear home range length was related to individual weight and to the river. Weight had a positive effect indicating a potential body condition effect, while river may be showing a habitat quality effect. Habitat preferences were positively affected by the abundance of helophytic vegetation and negatively by the presence of human activity. Helophytic vegetation offers both food and refuges, while human activity may represent a potential danger. Percentage of captures was higher inside the core areas and was slightly influenced positively by abundance of helophytic vegetation. All this information should be considered when designing and implementing measures to control the expansion of Amer- ican minks. We recommend keeping going with the trapping sessions but, given the results obtained, reducing the distance between traps down to 200 m to maximize capturability (i.e., about doubling the trapping effort), and, when available, placing them near helophytic vegetation. In the absence of helophytic vegetation, traps should be located near any kind of vegetation providing coverage for mink and far from human activity

Melero, Y., Palazon, S. and Gosalbez, J. 2008. Morphological adaptation of an invasive American mink population in Mediterranean areas of Spain. — Acta Zoologica (Stockholm) 89 : 47‐51 In this work we studied the morphology of an invasive population of American mink Mustela vison in Catalonia, Mediterranean Spain. Body weight, body length, tail length, hindfoot length and ear length were measured for four age‐sex classes: subadult male ( n = 17), subadult female ( n = 16), adult male ( n = 36) and adult female ( n = 10). A General Linear Mixed Model was used to test the effect of year, sex, age and age‐sex interaction, on each parameter. The morphological results differed from those of other introduced populations because of their different origin and their adaptation to different environments. Differences in sex and age were found, pointing to sexual dimorphism both in adults and subadults. The degree of dimorphism was lower than that of other populations, probably because of a lack of trophic niche separation between male and female mink because in the study area only small prey animals were available.

[Background] Multilocus data are becoming increasingly important in determining the phylogeny of closely related species and delimiting species. In species complexes where unequivocal fossil calibrations are not available, rigorous dating of the coalescence-based species trees requires accurate mutation rates of the loci under study but, generally, these rates are unknown. Here, we obtained lineage-specific mutation rates of these loci from a higher-level phylogeny with a reliable fossil record and investigated how different choices of mutation rates and species tree models affected the split time estimates. We implemented this strategy with a genus of water shrews, Neomys, whose taxonomy has been contentious over the last century., [Results] We sequenced 13 introns and cytochrome b from specimens of the three species currently recognized in this genus including two subspecies of N. anomalus that were originally described as species. A Bayesian multilocus species delimitation method and estimation of gene flow supported that these subspecies are distinct evolutionary lineages that should be treated as distinct species: N. anomalus (sensu stricto), limited to part of the Iberian Peninsula, and N. milleri, with a larger Eurasian range. We then estimated mutation rates from a Bayesian relaxed clock analysis of the mammalian orthologues with several fossil calibrations. Next, using the estimated Neomys-specific rates for each locus in an isolation-with-migration model, the split time for these sister taxa was dated at 0.40 Myr ago (with a 95 % confidence interval of 0.26 – 0.86 Myr), likely coinciding with one of the major glaciations of the Middle Pleistocene. We also showed that the extrapolation of non-specific rates or the use of simpler models would lead to very different split time estimates., [Conclusions] We showed that the estimation of rigorous lineage-specific mutation rates for each locus allows the inference of robust split times in a species tree framework. These times, in turn, afford a better understanding of the timeframe required to achieve isolation and, eventually, speciation in sister lineages. The application of species delimitation methods and an accurate dating strategy to the genus Neomys helped to clarify its controversial taxonomy., This work was financially supported by research project CGL2011-22640/BOS of the “Plan Nacional I + D + I del Ministerio de Ciencia e Innovación” (Spain) to J.C. with contribution of project 014/2008 of the “Convocatoria de ayudas a proyectos de investigación en la Red de Parques Nacionales” (Spain) to J.G. The research of A.A.B. was supported by the Russian Foundation for Basic Research, project 14-04-00034. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

This study describes the diet of European mink (Mustela lutreola) in Northern Spain. The diet was analysed from 105 European mink samples. Moreover, we collected other 37 faeces from a radiotracked European mink male. The European mink diet was based on small mammals (relative frequency of occurrences 36,9%), fish (30,6%) and birds (17,8%). The Levins index of trophic-niche width was 3,76. Wood mouse Apodemus sylvaticus was the most consumed small mammal and Cyprinids -mainly Barbus sp. was the most consumed fish. The average size and weight of consumed fish were 13,5 cm and 31,5 g, respectively and males consumed larger and heavier fish than females.

Adaptive models predict that variation in the spacing of microtines during reproductive periods may reflect mating strategies linked to differences in habitat characteristics. Using spatial and morphological analyses, we aimed to assess the mating system adopted by a population of rock-dwelling snow voles, Chionomys nivalis (Martins, 1842), and its functional significance within high-mountain environments. Spacing data coincided with a pattern generally associ - ated with promiscuous mating: males had largely overlapping home ranges, whereas female home ranges showed a very reduced or absent degree of overlap. In addition, ranges overlapped considerably between sexes. Males had signif- icantly greater body mass than females, and the magnitude of this difference resembled more a promiscuous than a polygamous or monogamous species. Also, relative testis size of males was in the range reported for promiscuous voles. Our results fit the predictions made by food abundance and distribution optimality models, suggesting that mat - ing strategies might be related to the habitat occupied by C. nivalis. In alpine rocky formations, vegetation is sparse and patchily distributed, and competing females could benefit from defending an exclusive territory. In turn, males might be unable to monopolize widely spaced females by defending exclusive territories, which may result in extensive overlap between their spatial ranges. Resume : Les modeles d'adaptation predisent que la variation de l'espacement des microtines durant la periode de re- production peut etre reliee a des strategies de reproduction associees aux differences de caracteristiques des habitats. Des analyses spatiales et morphologiques nous ont servi a evaluer le systeme d'accouplement adopte par une popula- tion de campagnols des neiges, Chionomys nivalis (Martins, 1842), et a faire des hypotheses sur son importance fonc- tionnelle dans les milieux de haute altitude. Les donnees sur l'espacement correspondent a un pattern generalement associe a un accouplement de promiscuite: les aires vitales des mâles se recoupent considerablement, alors que celles des femelles ont peu ou pas de recoupement. De plus, les aires vitales des deux sexes se chevauchent beaucoup. Les mâles ont une masse corporelle significativement plus grande que celle des femelles et l'importance de cette difference correspond plus a ce que l'on retrouve chez une espece qui pratique la promiscuite plutot que la polygamie. De plus, la taille relative des testicules des mâles se situe dans l'etendue des mesures signalees chez les especes qui pratiquent la promiscuite. Nos resultats concordent avec les predictions des modeles d'optimalite de l'abondance et de la reparti - tion de la nourriture, ce qui indique que les strategies d'accouplement sont peut-etre reliees a l'habitat occupe par C. nivalis. Comme la vegetation dans les formations rocheuses alpines est eparse et repartie de facon contagieuse, les femelles tirent sans doute un benefice de la defense d'un territoire exclusif. D'autre part, si les mâles defendaient un territoire, ils n'arriveraient probablement pas a s'assurer l'exclusivite des femelles eparses, ce qui explique l'important chevauchement dans leurs aires vitales.

The aim of this study was to examine how factors affecting male scent attractiveness to females interact with factors influencing male social dominance in rock-dwelling snow voles, Chionomys nivalis. We analysed the effect of particular phenotypic traits of male fitness, including relative body weight, bilateral asymmetry levels and haematocrit volume, upon relative success at both intra- and intersexual processes (measured as the outcome of social interactions among males and the level of attraction of males' odours to females, respectively). We found that males achieving more dominant status were those of higher relative body weight, which may give them physical advantage in intrasexual contests. Although social status of experimental males was not directly influenced by haematocrit volumes or levels of asymmetry, data from their original population indicate that relative heavier males are indeed more symmetric than lighter males. Regarding the attractiveness of male's odours, results show that relative body weight was unimportant to females, which principally favoured scents of individuals with higher haematocrit volumes. In addition, females tended to be more attracted towards the scents of less asymmetric males. These findings suggest that relative success of male C. nivalis at intra- and intersexual levels might be influenced by different factors. Nevertheless, due to the tight interrelationship between traits of male fitness, attraction to females and achievement of dominant status may not be completely independent. We further hypothesize that intrinsic information contained in male odour cues could be adaptively, and differently, used by conspecifics of both sexes in this species.

Human intervention is the main cause of the decline of the Critically Endangered European mink Mustela lutreola. In this study we analysed the main causes of direct human-caused mortality of the species in Spain. A total of 47 mortality records were obtained for the period 1950–1989, and 145 for 1990–2008. There was temporal variation in the cause of death, with trapping and shooting being the most common causes of mortality in 1950–1989 and road-kills in 1990–2008. In the case of road-kills there was variation related to road type. Males were more affected by road-kills than females, especially during the mating season when they range more widely. Our results indicate that there has been a change in human social behaviour and in people's awareness of the species, with a reduction in European mink captured and shot but an increase in mortality on roads.

Among microtine rodents, reaction to chemical cues from conspecifics is assumed to reflect social and spatial relationships. Generally, strong attraction of particular odours correlates with non-aggressive behaviour and high spatial tolerance towards odour donors, whereas weak attraction correlates with greater levels of aggression and spatial segregation. In the present study, we examined whether winter odour preferences of the snow vole Chionomys nivalis, a rock-dwelling microtine principally found at high-mountainous regions, differ from that of other vole species, owing to their different social organization during overwintering periods. The social structure of C. nivalis over the winter period is relatively unusual among vole species in that they become nomadic and solitary. In odour choice trials under laboratory conditions, we found that both males and females avoided zones with conspecific odours of both sexes in comparison with unscented control zones or own odours. These results are consistent with the elevated levels of intraspecific aggression and spatial isolation of C. nivalis during overwintering periods. Furthermore, scent-elicited self-grooming increased when their own odour was offered against conspecific cues. This, in combination with an active avoidance of conspecific odours, might functionally contribute to minimize direct confrontations between solitary individuals, thereby reducing the risks of aggressive encounters during overwintering periods.

We examined winter social behaviour of the snow voleChionomys nivalis Martins, 1842, a rock-dwelling microtine found principally in high-mountain biotopes. We conducted dyadic encounters among wild-caughtC. nivalis to determine patterns of intraspecific tolerance and the degree of aggressiveness between and within sexes during wintering periods. Our data show a high frequency of agonistic behaviours in all social encounters. Male pairs spent less time being aggressive than female pairs but more time in investigative behaviours. In contrast, the intensity of aggression displayed during interactions was significantly higher in male-male encounters than in female-female encounters, with an intermediate level of aggression in male-female encounters. The low degree of social tolerance found seems to be in agreement with the available data on the social organization of this species and further suggests that individuals may not spatially associate during over-wintering periods. Although both males and females were socially intolerant, the different patterns observed between the sexes may underlie different strategies.

We conducted a laboratory experiment to examine whether dominance status affects the use of locations occupied (i.e. scent-marked) by same-sex conspecifics among wild-caught snow vole males (Chionomys nivalis). Given that the costs of invading scent-marked areas should partially depend on the intruder's competitive ability, we hypothesised that, once a dominance relationship has been established with the owner of marks, the use of these areas by males would vary differently between dominant and subordinate individuals. Before any previous experience with the owner, scented substrates and nests were highly attractive to all males, indicating a general preference for recently occupied areas. However, after relative social status was established through direct interaction the subsequent response of males was altered differently, subordinate individuals reducing the use of marked areas to a much greater extent than dominants. Competitive relationships between male C. nivalis were found to be influenced by differences in body weight, larger males tending to display a more dominant pattern of behaviour. Our results reveal that male C. nivalis may require some direct experience with potential opponents to modulate their response towards occupied locations. Additionally, we suggest that the ability of males to conditionally respond to social signals from particular competing conspecifics might be used to lower the costs of prospective agonistic interactions.

This paper provides a criterion to determine the age of live Pyrenean desmansGalemys pyrenaicus (E. Geoffroy, 1811) by observing dental wear. The criterion is based on the comparison of the estimated age by examining the growth rings on dental sections and the wear observed on the upper canine tooth. Bone matter from different areas in the north of Spain was studied. This species has a high life expectancy. In its natural environment, the desman may live to be over 5 years old.

Environmental conditions in mountainous regions have influenced the nature of some adaptations among small mammals and this may apply to strategies of habitat use in alpine biotopes. In the present paper, microhabitat use in relation to microhabitat availability of a population of snow voles Chionomys nivalis Martins, 1842, a nonhibernating microtine rodent that inhabits high-mountain environments exclusively, was studied. The results show that C. nivalis did not use microhabitats in proportion to availability, suggesting a preference for certain habitat charac - teristics. Chionomys nivalis strongly used scree areas at all times, whereas the use of available areas of mixed shrubs (Juniperus communis and Cytisus oromediterraneus) and Scots pine (Pinus sylvestris) was lower than expected. Factors other than food, such as favourable microclimate or refuge from predators, might determine regular use of rocky microhabitats. The results also revealed differences in the use of rocky structures related to sex and reproductive condi - tion, suggesting different strategies of spatial use related to reproductive tasks. Juveniles and reproductive females used central zones of the scree and areas with scree junipers (J. communis) significantly more than expected, whereas repro- ductive males and nonreproductive adults used scree areas in proportion to availability. Based on its unique morpholog - ical, physiological, and ecological characteristics, C. nivalis can be considered a rock-dwelling specialist of alpine environments. Resume : Dans les zones montagneuses, les conditions environnementales ont influence la nature de certaines adapta- tions chez les petits mammiferes et cela peut etre vrai des strategies d'utilisation de l'habitat dans les biotopes alpins. On trouvera ici les resultats d'une etude sur l'utilisation des microhabitats en fonction de leur disponibilite chez une population de campagnols des neiges Chionomys nivalis Martins, 1842, un rongeur microtine qui n'hiberne pas et qui vit exclusivement dans les habitats de haute montagne. Les resultats indiquent que C. nivalis n'utilise pas les microha- bitats proportionnellement a leur disponibilite, ce qui laisse supposer l'existence d'une preference pour certaines carac- teristiques de l'habitat. Les campagnols frequentent beaucoup les zones d'eboulis en tout temps, alors qu'ils utilisent les zones buissonneuses mixtes (Juniperus communis et Cytisus oromediterraneus) et les zones de pins sylvestres (Pinus sylvestris) moins que prevu. Des facteurs autres que la nourriture, par exemple un microclimat favorable ou une protection contre les predateurs, peuvent expliquer l'utilisation reguliere des microhabitats rocheux. I l y a aussi des dif- ferences d'utilisation des structures rocheuses entre mâles et femelles et entre individus de statuts reproducteurs diffe - rents, ce qui suggere des strategies variables d'utilisation de l'espace selon les tâches reproductrices. Les juveniles et les femelles reproductrices frequentent les zones centrales des eboulis et les zones d'eboulis-genevriers ( J. communis) significativement plus que prevu, alors que les mâles reproducteurs et les adultes non reproducteurs utilisent les zones d'eboulis en fonction de leur disponibilite. Des caracteristiques morphologiques, physiologiques et ecologiques particu - lieres font de C. nivalis une espece specialiste des zones rocheuses des milieux alpins.

The ‘scent-matching’ hypothesis predicts that competitors could identify resource holders by investigating scent marks from a given area and matching these with the owner's odour when they meet. Previous studies on small rodents have supported the use of scent matching among males with mutually exclusive ranges. We designed an experiment to evaluate the potential role of scent matching in the snow vole, a species in which males have largely overlapping ranges but individually use specific locations within shared areas. Initial exploration of enclosures containing a choice between a scent-marked and an unmarked area established that males were more attracted to recently occupied areas. During a subsequent social encounter with either the donor of the scent marks present in the enclosure (matching opponent) or another male (nonmatching opponent), males were less aggressive towards matching than nonmatching opponents. Furthermore, during exploration of enclosures after encounters, males spent significantly less time at the scent-marked side after meeting a matching male but not after meeting another male. These results suggest that male snow voles may use scent matching to identify potential opponents and to respond differentially to occupied areas. By modifying their behaviour after assessing the identity of their opponents, males may be able to minimize current and prospective costly encounters with resource holders. Our findings show that the mechanism of scent matching is also compatible with spatial systems in which competing conspecifics possess overlapping ranges.

The use of trophic and spatial resources in a guild composed of five species of insectivorous mammals (Galemys pyrenaicus, Talpa europaea, Neomys fodiens, Sorex coronatus, and Sorex minutus) was studied. The characteristics of the macrohabitat were studied based on data from trap lines. Those pertaining to the microhabitat were examined through a study of the sites where each animal was caught. The diet was studied by analysis of the digestive tract as well as the availability of resources in various microhabitats. The results show a high level of segregation in the use of trophic resources. The microhabitat used on the ground surface has a low level of segregation among the shrews. A comparison of the diet of each species with the results from the invertebrate sampling carried out in different microhabitats (water, subsoil, humus, ground surface) shows that there is a relation between the food consumed and its availability in the microhabitats utilised by each species. This study suggests that the coexistence among the insectivorous species studied may be explained by the use of the microhabitat and diet segregation. The differences in diet would be a consequence of the use of different microhabitats.

In total, 298 transects (each 600 m long) were surveyed between 1987 and 1995 for otter Lutra lutra (Linnaeus, 1758) signs (spraints, smears and jellies) in nine rivers of NE Spain. Also two stretches of the rivers Noguera Ribagor^ana (length 2 km) and Noguera Pallaresa (length 2.6 km) in the Spanish Pyrenees were surveyed monthly between November 1989 and October 1990 for all otter tracks and signs. In both cases, all stones, rocks, beaches, hollows, caves, walls, shelves, and vegetation in the river and bankside within a 5 m band from the river edge (each side) were examined. The type of substrate on which findings were made was noted together with, the number of signs at a site. A seasonal pattern was found for the Pyrenean rivers with greatest sign density in winter and spring. In Mediterranean rivers, seasonality was not evident, founding even more signs in summer in some stretches. A total of 547.0 signs/km were recorded on the river Noguera Ribagor^ana during a year of study, of which 9.6% were smears, 1.0% jellies and 89.4% spraints. On the river Noguera Pallaresa 261.5 signs/km were noted, of which 9.2% were smears, 1.1% jellies and 89.7% spraints. A variation in sign deposition substrata (earth-beaches, grass, and rocks) and site (banks, middle river islands, caves/cracks, and river-stream confluences) throughout the year was observed. In the Noguera Ribagorgana stretch, periods of greatest sign deposition appear to be related to the presence of cubs. In accordance with the theory of the marking of resource use, a number of the spraints might not be significant, but rather the result of immature cub behaviour.

[Background] Species with strict ecological requirements may provide new insights into the forces that shaped the geographic variation of genetic diversity. The Pyrenean desman, Galemys pyrenaicus, is a small semi-aquatic mammal that inhabits clean streams of the northern half of the Iberian Peninsula and is endangered in most of its geographic range, but its genetic structure is currently unknown. While the stringent ecological demands derived from its aquatic habitat might have caused a partition of the genetic diversity among river basins, Pleistocene glaciations would have generated a genetic pattern related to glacial refugia., [Results] To study the relative importance of historical and ecological factors in the genetic structure of G. pyrenaicus, we used mitochondrial and intronic sequences of specimens covering most of the species range. We show, first, that the Pyrenean desman has very low levels of genetic diversity compared to other mammals. In addition, phylogenetic and dating analyses of the mitochondrial sequences reveal a strong phylogeographic structure of a Middle Pleistocene origin, suggesting that the main lineages arose during periods of glacial isolation. Furthermore, both the spatial distribution of nuclear and mitochondrial diversity and the results of species distribution modeling suggest the existence of a major glacial refugium in the northwestern part of the Iberian Peninsula. Finally, the main mitochondrial lineages show a striking parapatric distribution without any apparent exchange of mitochondrial haplotypes between the lineages that came into secondary contact (although with certain permeability to nuclear genes), indicating incomplete mixing after the post-glacial recolonization. On the other hand, when we analyzed the partition of the genetic diversity among river basins, the Pyrenean desman showed a lower than expected genetic differentiation among main rivers., [Conclusions] The analysis of mitochondrial and intronic markers in G. pyrenaicus showed the predominant effects of Pleistocene glaciations on the genetic structure of this species, while the distribution of the genetic diversity was not greatly influenced by the main river systems. These results and, particularly, the discovery of a marked phylogeographic structure, may have important implications for the conservation of the Pyrenean desman., We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI). This work was financially supported by research projects CGL2008-00434/BOS and CGL2011-22640/BOS of the Plan Nacional I + D + I del Ministerio de Ciencia e Innovación to J.C., and 014/2008 of the Convocatoria de ayudas a proyectos de investigación en la Red de Parques Nacionales to J.G.

The diet of Sorex coronatus (Millet, 1828) was studied by the analysis of digestive tracts from 178 individuals collected in Quinto Real Massif, western Pyrenees (north of the Iberian Peninsula). In total, 28 different types of food were determined. The most important prey species, as determined by numerical presence (N) and Simpson's dominance index (D"), were Chilopoda (%N = 12.8; D" = 21.4), Diptera larvae (%N = 22.0; D"= 17.7), Oligochaeta: Opistopora (%N = 11.3; D" = 12.2), Gastropoda (%N = 7.0; D" = 8.7), adult Coleoptera (%N = 6.9; D" = 8.0) and Hemiptera (%N = 6.0; D" = 5.3). Diets of both sexes were similar. The diet of S. coronatus in the study area was similar to the diet of S. araneus described in the literature.

Patterns of daily activity and the factors affecting it were studied in an invading Mediterranean population of American mink, Neovison vison, radiotracked in the northeast of Spain during the post breeding season (winter – half year). We distinguished between local activity, defined as active behaviour without spatial displacement, locomotion activity as active locomotion behaviour while foraging or travelling, and inactivity. We studied the effect of sex, age, daylight (nocturnal or diurnal), month, river flow and average rainfall on the activity of eight males and three females. Male mink presented more locomotion activity than females and subadult mink had more locomotion activity than adult mink. Average rainfall per day had a negative effect on locomotion, while daylight had no effect on either total activity or locomotion activity. Studied mink spent most of their time inactive in-den. These results are accordance with the patterns of activity shown by other native and invasive populations.

Les modifications de la distribution du vison d'Europe (Mustela lutreola) entre 1950 et 1999 sont decrites, avec 258 nouvelles donnees pour l'espece. Toutes les donnees proviennent du nord de l'Espagne (Pays basque, Rioja, Navarre, NO Aragon, NE Castilla-Leon) avec quelques-unes du sud de la Catalogne. Le type de donnees s'est modifie au cours du temps. La quantite d'animaux tues par l'homme a diminue alors que la mortalite due a la route a augmente. Entre 1980 et 1999, les visons ont ete trouves dans 99 carres UTM (10 x 10 km), et dans seulement 85 carres depuis 1990 (2,0 % et 1,8 % du territoire espagnol, respectivement). M.lutreola existe sous forme de trois noyaux de populations, plus ou moins connectes. On peut emettre deux hypotheses principales pour expliquer la repartition actuelle du vison d'Europe en Espagne; (1) M lutreola se trouve en Espagne depuis avant le XIX e siecle, au sein de son aire historique, et (2) M. lutreola a rejoint l'Espagne recemment (au cours du XX e siecle) a partir du SO de la France, par une extension au sud. Nos donnees semblent confirmer cette derniere hypothese. Meme si des visons d'Europe ont ete trouves dans des rivieres fortement polluees, ils evitent en general les eaux polluees. De plus, l'etablissement, a l'interieur de l'aire de repartition du vison d'Europe, d'une population de visons d'Amerique dans le nord de l'Espagne, et l'expansion de la grosse population de visons americains depuis le centre de l'Espagne, ainsi que la presence d'ADVirus chez plusieurs visons d'Europe constituent de serieuses menaces pour sa survie en Espagne.

Department of Animal Biology (Vertebrates), University of Barcelona, Av. Diagonal 645, 08028 Barcelona, Spain Biodiversity and Animal Protection Service, General Direction of Environment and Biodiversity, Catalonia Government, Doctor Roux, 80, 08017 Barcelona, Spain Tragsatec, Division of Environmental Servicies, Julian Camarillo, 6B-4 D, 28037 Madrid, Spain Aranzadi Society of Sciences, Department of Vertebrates, Zorroagagaina kalea, 11, 20014 Donostia-San Sebastian, Spain

Des donnees sur la structure de population d'Arvicola terrestris de la Vallee d'Aran (Lerida, Espagne), en relation avec l'âge relatif, sont presentees. 684 individus (340 ♂ et 380 ♀) ont ete pieges de juillet 1983 a decembre 1984, dans les pâturages de la rive gauche de la Garonne, entre les villages d'Arros et Aubert. Les individus captures ont ete distribues, selon les caracteristiques du pelage, de la mue, de la morphologie crânienne, de l'etat sexuel et des donnees morpho- et craniometriques, en six classes d'âge relatif (0-V). Les resultats obtenus sont en accord avec la dynamique de reproduction de la population (...)

The breeding season of Talpa europaea Linnaeus, 1758, in the NE of the Iberian Peninsula lasts from December to June, with maximum activity from January to March. Both males and females reach sexual maturity once they have completed their first year. The number of embryos per litter is neither connected with the age of the female nor the month of capture. The length breeding season in the area studied implies that some females may have two or even three litters per year under favourable conditions. The average number of embryos per female in the population, as a whole, is 3.12 (n=17). The differences noted in comparison with other European populations can be attributed to the differing climatic conditions which are directly related to the timing of the breeding season.

Diet composition, niche measures, and prey consumption of three sympatric species of carnivores, one non-native and introduced, the American minkNeovison vison Schreber, 1777, and two native, the spotted genetGenetta genetta Linnaeus, 1758 and the Eurasian otterLutra lutra Linnaeus, 1758, were studied in a Spanish Mediterranean area. The study was based on the analysis of prey remains in the faeces of the predators. Faeces of mink (n = 444), genet (n = 310), and otter (n = 108) were collected all year round for four years along the Llobregat (21 km) and Gavarresa rivers (12 km). Simultaneously, and in the same area, prey species density and weight were estimated by means of trapping. The diet of mink and genet was dominated by the American crayfishProcambarus clarkii, while the otter fed almost exclusively on fish. Compared to the mink, the genet seemed to specialise more on small mammals while the mink specialised more on aquatic birds, especially in autumn-winter. Niche overlap was higher between mink and genet than between either of them and the otter.