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Santa Cruz de la Palma, Spain

Reque J.A.,University of Valladolid | Martin E.,Consejeria de Medio Ambiente
Forest Systems | Year: 2015

Aim of the study: a) To present the trial-and-error approach followed in the design and patent of a manufactured seed and seedling protector effective against mice and voles, rabbits, wild boar and deer (http://bopiweb.com/elemento/829172/). b) To assess the viability of direct oak seeding with and without protection in the complex acorn predation reality of post fire restoration and under-planting in existing pine afforestations. Study area: Northern Plateau of Spain, in an area of extreme acorn predation. Material and methods: We followed a classical trial-and-error approach for problem solving. Different modifications to a wire mesh screen cylinder were tested in subsequent trials aiming to evaluate the effects on acorn predation and early emerging plant survival and growth. The final protector is based on a thin wire mesh cylinder with three innovations: a truncated cone, a circular crown and a sphere compartment. Further we assessed the viability of direct oak seeding with and without protection in the complex acorn predation reality of post fire restoration and underplanting in existing pine afforestations. Main results: The manufactured seed protector was found to be effective against synergic attacks of mice, rodents, wild boars and herbivores. Survival of protected oak was 77% under canopies and 32% in open light conditions two years after sowing. Research highlights: Our results confirm the viability of direct oak seeding for woodland restoration if seed predation is controlled. © 2015 INIA. Source


Jalut G.,CNRS Functional Ecology & Environment Laboratory | Turu i Michels V.,Fundacio Marcel Chevallier | Dedoubat J.-J.,CNRS Functional Ecology & Environment Laboratory | Otto T.,CNRS Functional Ecology & Environment Laboratory | And 8 more authors.
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2010

At the north-western limit of the Mediterranean basin, in the Mediterranean-Oceanic transition zone, the multidisciplinary study of two palaeolakes: Villaseca and La Mata (Province of Leon), provides data on the last deglaciation. The juxtaglacial lakes were formed during a deglaciation phase of the last cold stage (Weichselian/Würm) estimated, from the regional and Pyrenean chronological data, between circa 48. ka and 32. ka (ka: 1000. years ago). Their drainage occurred circa 17. ka and 15. ka respectively, during the definitive glacial retreat phases. These results provide evidence for a glacial maximum extension preceding the global Last Glacial Maximum (LGM) and an early deglaciation. Comparisons with the Pyrenean data show that in the most important glacial basins of the Pyrenean-Cantabrian range, glaciers were still present at middle elevation circa 18-20. ka. The final deglaciation did not happen until around 16. ka.During the period 48-13.3ka, along the Pyrenean-Cantabrian range, three stages can be distinguished in the deglacial processes. Between circa 48 and 32ka, the deglacial retreats were contemporaneous with D-O events 12 to 6. Between circa 32ka and 18ka, major sedimentary modifications were rare. Two of them are synchronous with D-O 4 and 3. A glacial readvance also occurred during this period along the Pyrenean-Cantabrian range. Between 18 and 17ka, major sedimentary changes and an increase in the δ18O records of the NGRIP ice-core record are synchronous. Between 15 and 13.3ka, glacial retreats and sedimentary changes are synchronous with the climatic improvement observed from the end of the Oldest Dryas to the end of the Bölling-Alleröd period.These correspondencies suggest relationships between the deglacial processes in the western Mediterranean and the palaeoenvironmental events in the North Atlantic region during the last Glacial-Interglacial transition. During the Full Glacial period, the pollen data indicates dominant steppic environments. The Oldest Dryas was not a constant cooling phase and from around 15.5. ka, the pollen data indicates a slight warming. During the Holocene, until circa 2040. cal BP, mixed oak forests developed and pine was a prominent component of the Cantabrian landscape. Then the forests were destroyed due to mining, agriculture and fire, and this favoured the extension of heathland. © 2010. Source


Dana E.D.,Egmasa Consejeria de Medio Ambiente | Lopez-Santiago J.,Egmasa Consejeria de Medio Ambiente | Garcia-de-Lomas J.,Egmasa Consejeria de Medio Ambiente | Garcia-Ocana D.M.,Egmasa Consejeria de Medio Ambiente | And 2 more authors.
Aquatic Invasions | Year: 2010

Pacifastacus leniusculus (an invasive species in European water bodies) was detected for the first time in the Andalusia Region (S. Spain) in the year 2000. Since 2005, a continuous control management programme has been carried out by the Environmental Regional Government. Management efforts aimed to reduce the population size, to contain the dispersal and reduce the probability of deliberate translocation into other rivers caused by illegal captures. A combination of techniques was used, including crayfish traps, manual removal from artificial refuges and electrofishing. In the 2005-2009 period, 31 374 specimens were captured. The mean catch rate per worker and day declined from 30.4 ± 3.2 specimens in the first year to 9.8 ± 1.7 in the fourth year, therefore suggesting a sharp decrease in population size. Summer was the period of mating and maximum yields, whereas minimum yields were obtained in Winter, coinciding with egg incubation in burrows. The results obtained and the experience gained will provide essential baseline information for the future management of non-native crayfish in the region. © 2010 The Author(s). Source


Bonnaud E.,Aix - Marseille University | Bonnaud E.,University Paris - Sud | Medina F.M.,Consejeria de Medio Ambiente | Vidal E.,Aix - Marseille University | And 8 more authors.
Biological Invasions | Year: 2011

Cats are among the most successful and damaging invaders on islands and a significant driver of extinction and endangerment. Better understanding of their ecology can improve effective management actions such as eradication. We reviewed 72 studies of insular feral cat diet from 40 islands worldwide. Cats fed on a wide range of species from large birds and medium sized mammals to small insects with at least 248 species consumed (27 mammals, 113 birds, 34 reptiles, 3 amphibians, 2 fish and 69 invertebrates). Three mammals, 29 birds and 3 reptiles recorded in the diet of cats are listed as threatened by the IUCN. However, a few species of introduced mammals were the most frequent prey, and on almost all islands mammals and birds contributed most of the daily food intake. Latitude was positively correlated with the predation of rabbits and negatively with the predation of reptiles and invertebrates. Distance from landmass was positively correlated with predation on birds and negatively correlated with the predation of reptiles. The broad range of taxa consumed by feral cats on islands suggests that they have the potential to impact almost any native species, even the smallest ones under several grams, that lack behavioral, morphological or life history adaptations to mammalian predators. Insular feral cat's reliance on introduced mammals, which evolved with cat predation, suggests that on many islands, populations of native species have already been reduced. © 2010 Springer Science+Business Media B.V. Source


Balmori A.,Consejeria de Medio Ambiente
Science of the Total Environment | Year: 2016

Radio transmitters and associated devices may induce negative effects that can bias the results of ongoing research. The main documented effects of radio transmitters on animals include reduced survival, decreased productivity, changes in behaviour and movement patterns and a biased sex ratio. The only factors that have claimed responsibility for these possible damages are the weight of the radio transmitter and associated devices, and the attachment type. The electromagnetic radiation produced by radio transmitters has not been considered so far in research. There have been no studies evaluating the effects of non-ionising electromagnetic radiation (radiofrequency signals) necessary for tracking, although the problems found were significantly associated with the length of time that animals had been carrying their radio transmitters. Similar problems as those in radiotracked animals have been found in numerous studies with animals exposed to radiofrequency radiation for a sufficient amount of time. Laboratory scientists investigating the orientation of animals know they have to shield the place where experiments are performed to prevent interference from man-made radiation, as anthropogenic signals may distort the results. It is paradoxical that, at the same time, field scientists investigating the movements and other aspects of animal biology are providing animals with radio transmitters that emit the same type of radiation, since this may affect the results concerning their orientation and movement. This paper identifies gaps in the knowledge that should be investigated in-depth. The possibility that the radiofrequency radiation from radiotracking devices is responsible for the findings should be considered. Considering this factor may allow researchers to best understand the long-term effects found. © 2015 Elsevier B.V. Source

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