Botias C.,Centro Apicola Regional CAR |
Martin-Hernandez R.,Centro Apicola Regional CAR |
Martin-Hernandez R.,Institute Recursos Humanos Para la Ciencia y la Tecnologia INCRECYT |
Garrido-Bailon E.,Centro Apicola Regional CAR |
And 5 more authors.
Research in Veterinary Science | Year: 2012
Microsporidiosis caused by infection with Nosema apis or Nosema ceranae has become one of the most widespread diseases of honey bees and can cause important economic losses for beekeepers. Honey can be contaminated by spores of both species and it has been reported as a suitable matrix to study the field prevalence of other honey bee sporulated pathogens. Historical honey sample collections from the CAR laboratory (Centro Apícola Regional) were analyzed by PCR to identify the earliest instance of emergence, and to determine whether the presence of Nosema spp. in honey was linked to the spread of these microsporidia in honey bee apiaries. A total of 240 frozen honey samples were analyzed by PCR and the results compared with rates of Nosema spp. infection in worker bee samples from different years and geographical areas. The presence of Nosema spp. in hive-stored honey from naturally infected honey bee colonies (from an experimental apiary) was also monitored, and although collected honey bees resulted in a more suitable sample to study the presence of microsporidian parasites in the colonies, a high probability of finding Nosema spp. in their hive-stored honey was observed. The first honey sample in which N. ceranae was detected dates back to the year 2000. In subsequent years, the number of samples containing N. ceranae tended to increase, as did the detection of Nosema spp. in adult worker bees. The presence of N. ceranae as early as 2000, long before generalized bee depopulation and colony losses in 2004 may be consistent with a long incubation period for nosemosis type C or related with other unknown factors. The current prevalence of nosemosis, primarily due to N. ceranae, has reached epidemic levels in Spain as confirmed by the analysis of worker honey bees and commercial honey. © 2011 Elsevier Ltd.
PubMed | Institute of Research in Game Resources CSIC, Tragsatec, S.L. Perpetuo Socorro no12 Entresuelo, University of Oviedo and Subdireccion General de Medio Natural
Type: Journal Article | Journal: Conservation biology : the journal of the Society for Conservation Biology | Year: 2016
In many cases, the first step in large-carnivore management is to obtain objective, reliable, and cost-effective estimates of population parameters through procedures that are reproducible over time. However, monitoring predators over large areas is difficult, and the data have a high level of uncertainty. We devised a practical multimethod and multistate modeling approach based on Bayesian hierarchical-site-occupancy models that combined multiple survey methods to estimate different population states for use in monitoring large predators at a regional scale. We used wolves (Canis lupus) as our model species and generated reliable estimates of the number of sites with wolf reproduction (presence of pups). We used 2 wolf data sets from Spain (Western Galicia in 2013 and Asturias in 2004) to test the approach. Based on howling surveys, the nave estimation (i.e., estimate based only on observations) of the number of sites with reproduction was 9 and 25 sites in Western Galicia and Asturias, respectively. Our model showed 33.4 (SD 9.6) and 34.4 (3.9) sites with wolf reproduction, respectively. The number of occupied sites with wolf reproduction was 0.67 (SD 0.19) and 0.76 (0.11), respectively. This approach can be used to design more cost-effective monitoring programs (i.e., to define the sampling effort needed per site). Our approach should inspire well-coordinated surveys across multiple administrative borders and populations and lead to improved decision making for management of large carnivores on a landscape level. The use of this Bayesian framework provides a simple way to visualize the degree of uncertainty around population-parameter estimates and thus provides managers and stakeholders an intuitive approach to interpreting monitoring results. Our approach can be widely applied to large spatial scales in wildlife monitoring where detection probabilities differ between population states and where several methods are being used to estimate different population parameters.
Banha F.,University of Évora |
Gimeno I.,CSIC - Pyrenean Institute of Ecology |
Lanao M.,Tragsatec |
Touya V.,Area de Calidad de las Aguas |
And 3 more authors.
Biological Invasions | Year: 2016
The zebra mussel, Dreissena polymorpha (Pallas 1771), is an invasive freshwater species with major negative impacts, promoting changes in ecosystem structure and function and also contributing to economic losses. Navigation has been considered the primary vector of dispersion and little importance has been given to alternative natural (waterbirds) and other human vectors. Using an experimental approach under field conditions, we evaluated and compared zebra mussel dispersal potential by fishing gear (waders and keepnets) versus mallard ducks (Anas platyrhynchos), by examining the adherence and survival rate of zebra mussel larvae on each vector. In addition, we evaluated the survival of zebra mussel larvae under desiccating conditions (i.e., a set of controlled temperatures and relative humidities). Larvae adhered to all types of vectors and survived desiccation under both laboratory and field conditions and thus appear able to be dispersed long distances overland by both ducks and fishing gear. Specifically, on a per-event basis, fishing gear has a higher potential to spread zebra mussel larvae than ducks. Survival was three times higher on human vectors and the number of larvae attached to human vectors was over double of that on the ducks. However, our findings demonstrate that natural vectors, like ducks, can contribute to the transport of zebra mussel larvae at a local scale. Nevertheless, since vectors related to human activity presented a higher potential for transport, it is imperative to continue campaigns to raise the awareness of anglers and boaters as well as continue the implementation of legislation to reduce the risk of zebra mussel dispersal. © 2015, Springer International Publishing Switzerland.
Igea J.,Institute Of Biologia Evolutiva Csic Upf |
Igea J.,Imperial College London |
Aymerich P.,University of Barcelona |
Fernandez-Gonzalez A.,Biosfera Consultoria Medioambiental S.L |
And 5 more authors.
BMC Evolutionary Biology | Year: 2013
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. © 2013 Igea et al.; licensee BioMed Central Ltd.
Podra M.,University of Barcelona |
Podra M.,Tallinn University |
Gomez A.,TRAGSATEC |
Palazon S.,University of Barcelona
European Journal of Wildlife Research | Year: 2013
An experimental release of the European mink (Mustela lutreola) was carried out in the Salburua wetland in North Spain between 2008 and 2010. A partial removal of feral American mink (Neovison vison) was done preceding the release. The survival and the cause of death of each of 27 captive-bred minks were studied during five months after release. Only 22 % of the minks (N = 6) survived during whole radio-tracking period. Predation was the most significant cause of mortality (76 %, N = 16). Seven European minks (33 % of mortality) were killed by another "mink-size" carnivore-the causes of death of these individuals were of particular interest to clarify possible impact of a few remained American mink to released European mink. We used three criteria to identify the exact causes of death of these seven minks: 1. Comparison of the distances of bite marks with the inter-canine distances of small carnivores, 2. Site descriptions and signs of predators and 3. Density of carnivores within the study area. None of the criteria taken separately allowed the complete identification of the predator species. Summing up the results of all three criteria, a male American mink was found to be the most likely predator of at least six released European minks (29 % of overall mortality and 38 % of predated minks). Our results show that the presence of American mink, even if the number is estimated to be low, may seriously limit the success of reinforcement or reintroduction of the European mink. © 2013 Springer-Verlag Berlin Heidelberg.
Palazon S.,Ramaderia |
Melero Y.,University of Barcelona |
Gomez A.,Tragsatec |
Lopez De Luzuriaga J.,Asociacion Vison Europeo |
And 2 more authors.
ORYX | Year: 2012
Abstract 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. © 2012 Fauna & Flora International.
Duran C.,Ebro Hydrographic Confederation |
Lanao M.,Tragsatec |
Anadon A.,Tragsatec |
Touya V.,Ebro Hydrographic Confederation
Aquatic Invasions | Year: 2010
Dreissena polymorpha has invaded seven rivers in the Ebro River basin (Spain) in the period 2001-2009. In this paper, we present a compilation of management strategies directed by the Ebro Hydrographic Confederation (CHE) with the aim of showing the different steps taken by this organisation to prevent the spread of this invader. These practical procedures are accompanied by diverse educational materials to inform and make people aware of the importance of this problem. The experience gained during these years has allowed the establishment of both an adequate sampling schedule and a sampling method for larval monitoring with the purpose of detection of zebra mussel populations. On the other hand, we have observed that mechanical cleaning and drying techniques are the physical control methods most frequently used by affected users in the Ebro basin, with use of chlorine as chemical method. © 2010 The Author(s).
Escalante E.F.,Tragsa IDi |
Gil R.C.,Tragsa IDi |
Fraile M.A.S.M.,Tragsatec |
Water (Switzerland) | Year: 2014
This paper investigates the economic aspects of Managed Aquifer Recharge (MAR) techniques considered in the DINA-MAR (Depth Investigation of New Areas for Managed Aquifer Recharge in Spain) project. This project firstly identified the areas with potential for MAR for the whole of the Iberian Peninsula and Balearic Islands of Spain using characteristics derived from 23 GIS layers of physiographic features, spanning geology, topography, land use, water sources and including existing MAR sites. The work involved evaluations for 24 different types (techniques) of MAR projects, over this whole area accounting for the physiographic features that favor each technique. The scores for each feature for each type of technique were set based on practical considerations and scores were accumulated for each location. A weighting was assigned to each feature by “training“ the integrated score for each technique across all the features with the existing MAR sites overlay, so that opportunities for each technique could be more reliably predicted. It was found that there were opportunities for MAR for 16% of the area evaluated and that the additional storage capacity of aquifers in these areas was more than 2.5 times the total storage capacity of all existing surface water dams in Spain. The second part of this work, which is considered internationally unique, was to use this GIS methodology to evaluate the economics of the various MAR techniques across the region. This involved determining an economic index related to key physiographic features and applying this as an additional GIS overlay. Again this was trained by use of economic information for each of the existing MAR sites for which economic data and supply or storage volume were available. Two simpler methods were also used for comparison. Finally, the mean costs of MAR facilities and construction projects were determined based on the origin of the water. Maps of potential sites for Managed Aquifer Recharge (or “MAR zones“) in the Iberian Peninsula and Balearic Islands of Spain and the results of the previous economic studies developed at the beginning of the project were used as the foundation for the economic analysis. Based on these data, a new specific mapping of the total expected costs for all “MAR zones“ (€/m3) was proposed based on the techniques that were considered most appropriate for each Spanish study case. Capital costs ranged from Euro 0.08-0.58 per m3/year. Overall, this study investigates the opportunity and economic feasibility of implementing new MAR projects and provides support to decision makers in Spain. The novel mapping provides valuable guidance for the future development of Managed Aquifer Recharge projects for water managers and practitioners. © 2014 by the authors.
Huhn F.,University of Santiago de Compostela |
von Kameke A.,University of Santiago de Compostela |
Allen-Perkins S.,TRAGSATEC |
Montero P.,INTECMAR |
And 2 more authors.
Continental Shelf Research | Year: 2012
Horizontal Lagrangian surface transport is studied in the Ria de Vigo, an estuary in NW Spain with tidal and wind-driven dynamics. Surface drifters and the surface flow from a high-resolution 3-D hydrodynamic model are compared to each other. In particular, our analysis is based on a classical comparison of real and artificial trajectories and on Lagrangian Coherent Structures (LCS) defined as ridges in spatial fields of the Finite-Time Lyapunov Exponent (FTLE). The trajectories of the drifters are in good agreement with the prediction of the model in two out of four cases. Further, FTLE ridges computed from the model velocity fields are found to mark transport barriers for the drifters. The results indicate that the model is able to represent the general circulation in the estuary. Main patterns in the Lagrangian surface transport in the model are shown for two typical meteorological situations, north wind and south wind. They can be interpreted as an imprint of a 3-dimensional circulation pattern in the Ria de Vigo and reveal in detail the separation of the time-dependent in- and outflow at the surface of the estuary. © 2012 Elsevier Ltd.
PubMed | Tragsatec, Institute Investigacion en Recursos Cinegeticos CSIC UCLM JCCM, Subdireccion General de Medio Natural. Ministerio de Agricultura and University of Oviedo
Type: | Journal: Scientific reports | Year: 2017
Obtaining reliable estimates of the structure of carnivore communities is of paramount importance because of their ecological roles, ecosystem services and impact on biodiversity conservation, but they are still scarce. This information is key for carnivore management: to build support for and acceptance of management decisions and policies it is crucial that those decisions are based on robust and high quality information. Here, we combined camera and live-trapping surveys, as well as telemetry data, with spatially-explicit Bayesian models to show the usefulness of an integrated multi-method and multi-model approach to monitor carnivore community structures. Our methods account for imperfect detection and effectively deal with species with non-recognizable individuals. In our Mediterranean study system, the terrestrial carnivore community was dominated by red foxes (0.410 individuals/km