San Juan de la Rambla, Spain
San Juan de la Rambla, Spain

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Palacios V.,S.L. Perpetuo Socorro no12 Entresuelo | Garcia E.J.,S.L. Perpetuo Socorro no12 Entresuelo | Llaneza L.,S.L. Perpetuo Socorro no12 Entresuelo | Garcia-Dominguez F.,Subdireccion General de Medio Natural | And 2 more authors.
European Journal of Wildlife Research | Year: 2016

GPS collars are commonly used to estimate predation and scavenging rates in large carnivores. However, little information is available on the impact of different schedules on feeding site detection rates. Here, we evaluated the effect of different GPS schedules on the detection rate of wolves’ feeding sites in a human-dominated landscape of NW Iberia (Galicia), where the main food sources for wolves were large livestock ungulates (horses and cattle). Combining an intensive GPS schedule of 20 min time intervals between locations, used as reference values, with the field examination of clusters of locations, on average, we observed a 40 and 24 % decrease in clusters and events detection rates from 20 to 40 min, respectively, and a 13 and 15 % decrease from 40 to 60 min, respectively. On the other hand, on a subset of monitoring days, from 10 to 20 min, the proportion of events detected decreased by 6 %. The decrease in detection rates over time was similar across livestock species and age classes. It is worth noting that the decrease in detection rates was higher for scavenging events, which can be common in human-dominated landscapes, compared to predation events. Our results indicate that using long time intervals between locations to study wolf feeding behavior in human-dominated landscapes will underestimate not only predation rates, but also the importance of scavenging events. Since a 10-min schedule reduces the expected battery life of collars notably and the decrease in detection rate was low between 10 and 20 min, compared to 20 min and the longer time intervals explored, we recommend a GPS schedule of 20 min to study the feeding behavior of wolves in human-dominated landscapes. © 2016 Springer-Verlag Berlin Heidelberg


The present Atlantic range of the Mediterranean monk seal (Monachus monachus), a critically endangered species, comprises two populations in the Desertas Islands and Cape Blanco region. The species is currently the subject of an action plan that encourages the recolonization of its former range. I investigated their causes of its disappearance using species records from paleo-archeological sites and historical sightings/toponyms. I hypothesize that the species' prehistoric range extended from the continental coasts of North Africa to the Iberian Peninsula, an area larger than its current known range. It is further hypothesized that the historic range included at least 13 colonies, seven more than the present number; and that the original optimal breeding habitat was open beaches, while sea caves were a suboptimal, marginal habitat. It is suggested that hunting and the disappearance of two islands due to a historical tsunami event explain the disappearance of the other populations, leaving only those at the Desertas Islands and Cape Blanco that were sheltered in sea caves. Furthermore, the use of sea caves, in conjunction with effective legal protection in the 20th century, explains the present-day survival of these Atlantic colonies of M. monachus. © 2015 Society for Marine Mammalogy.


Gonzalez L.M.,Subdireccion General de Medio Natural | Montoto F.G.D.,Subdireccion General de Medio Natural | Mereck T.,Fundacion CBD Habitat | Alves J.,Fundacion CBD Habitat | And 5 more authors.
ORYX | Year: 2016

Guinea-Bissau is host to the westernmost subpopulation of the common hippopotamus Hippopotamus amphibius, which is one of only two known populations inhabiting coastal waters. The presence of hippopotamuses causes conflict with rice farmers as a result of crop damage and the absence of effective measures to protect crops. To develop an effective method for protecting rice fields, we studied the patterns of access to flooded and rain-fed rice fields by hippopotamuses and assessed the effect of the installation of electric fences. Hippopotamuses were detected in 54% of the flooded fields (n = 100) and in 31.9% of the rain-fed fields (n = 91). They were detected more frequently in fields on offshore islands than on the mainland, in unfenced than in fenced fields, and in fields closer to running water. Hippopotamuses entered fenced flooded fields less frequently than unfenced, and were detected most frequently at the end of the rainy season and the start of the dry season, and in the period of vegetative stem growth. Electric fences were an effective deterrent and facilitated increased rice production. The maintenance and cost of the electric fencing were acceptable to farmers, and therefore the use of such fencing is recommended to resolve the conflict between hippopotamuses and farmers in Guinea-Bissau and in other areas with similar conditions. Copyright © Fauna & Flora International 2016


Jimenez J.,Institute Of Research In Game Resources Csic Ronda Of Toledo S N | Garcia E.J.,A.RE.NA. Asesores en Recursos Naturales S.L. Perpetuo Socorro no 12 Entresuelo | Llaneza L.,A.RE.NA. Asesores en Recursos Naturales S.L. Perpetuo Socorro no 12 Entresuelo | Palacios V.,A.RE.NA. Asesores en Recursos Naturales S.L. Perpetuo Socorro no 12 Entresuelo | And 4 more authors.
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 naïve 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. © 2016, Society for Conservation Biology.


Jimenez J.,Institute of Research in Game Resources CSIC | Garcia E.J.,S.L. Perpetuo Socorro no12 Entresuelo | Llaneza L.,S.L. Perpetuo Socorro no12 Entresuelo | Palacios V.,S.L. Perpetuo Socorro no12 Entresuelo | And 4 more authors.
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 naïve 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. © 2016 Society for Conservation Biology


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.

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