New member of GEDA

Ainara Cortés-Avizanda has joined the GEDA for a 2-year postdoctoral position. She will be working on the ecology of the Griffon vulture. A species that has recently clonized Mallorca following an unusal storm. A rare case of natural colonization by a large species. Welcome Ainara!

Award by the Spanish Society of Evolutionary Biology !

The work on the evolutionary demography of the Belearic Wall lizard by A. Rotger presented at the VI Congress of the Spanish Society of Evolutionary Biology was awarded with the 2nd prize for the best scientific poster. 


Well done Andreu!

New Publication on Vulture Ecology: movements and sanitary regulations !

Arrondo, E., Moleón, M., Cortés-Avizanda, A., Jiménez, J., Beja, P., Sánchez-Zapata, J.A, Donázar, J.A. 2018. Invisible barriers: Differential sanitary regulations constrain vulture movements across country borders. Biological Conservation, 219: 46-52. doi.org/10.1016/j.biocon.2017.12.039

Abstract: Political boundaries may represent ecological barriers due to differences in wildlife management policies. In the European Union, it might be expected that these differences should be highly diluted, because all countries have to comply with common directives issued by the European Commission. However, the subsidiarity principle may lead to the uneven uptake of European Union regulations, which can impact on biodiversity conservation due to unequal legislation in neighboring countries, particularly in the case of highly mobile organisms.

Photo: M. Gomila (@miknuk)

Here we address this issue, by analyzing how EU regulations issued in response to the Bovine Spongiform Encephalopathy (BSE) crisis differentially affected vulture conservation in Portugal and Spain. Gyps fulvus) and 11 cinereous vultures (Aegypius monachus) from Spain, we found that the Spanish-Portuguese border acts as a quasi-impermeable barrier. In fact, there was an abrupt decline in the number of vulture locations across the Spanish-Portuguese border, with modelling showing that this was unlikely to be related to differences in land cover or topography. Instead, the pattern found was likely due to differences in trophic resource availability, namely carcasses from extensive livestock husbandry, resulting from the differential application of European sanitary legislation regarding the mandatory removal of dead livestock from the field. Overall, our results should be seen as a warning signal to policy makers and conservation managers, highlighting the need for a stronger integration of sanitary and environmental policies at the European level.

New Publication on seabird mortality and fishery !

Genovart M, Bécares J, Igual J-M, Martinez-Abrain, A., Escandell, R., Sánchez, A., Rodriguez, R., Arcos, J.-M., Oro, D. 2018 Differentialadult survival at close seabird colonies: The importance of spatial foragingsegregation and bycatch risk during the breeding season. Global Change Biology.00:1–13. https://doi.org/10.1111/gcb.13997

Abstract: Marine megafauna, including seabirds, are critically affected by fisheries bycatch. However, bycatch risk may differ on temporal and spatial scales due to the uneven distribution and effort of fleets operating different fishing gear, and to focal species distribution and foraging behavior. Scopoli's shearwater Calonectris diomedea is a long-lived seabird that experiences high bycatch rates in longline fisheries and strong population-level impacts due to this type of anthropogenic mortality. Analyzing a long-term dataset on individual monitoring, we compared adult survival (by means of multi-event capture–recapture models) among three close predator-free Mediterranean colonies of the species. Unexpectedly for a long-lived organism, adult survival varied among colonies. We explored potential causes of this differential survival by (1) measuring egg volume as a proxy of food availability and parental condition; (2) building a specific longline bycatch risk map for the species; and (3) assessing the distribution patterns of breeding birds from the three study colonies via GPS tracking. Egg volume was very similar between colonies over time, suggesting that environmental variability related to habitat foraging suitability was not the main cause of differential survival. On the other hand, differences in foraging movements among individuals from the three colonies expose them to differential mortality risk, which likely influenced the observed differences in adult survival. The overlap of information obtained by the generation of specific bycatch risk maps, the quantification of population demographic parameters, and the foraging spatial analysis should inform managers about differential sensitivity to the anthropogenic impact at mesoscale level and guide decisions depending on the spatial configuration of local populations. The approach would apply and should be considered in any species where foraging distribution is colony-specific and mortality risk varies spatially. 

You can see more information in the Press Note by IMEDEA here (in Spanish)

Back to the Balearic Islands (part II) !

The gulls equipped with a GSM/GPS device are slowly coming back to the Balearic Islands. This bird (image below) has stopped at the same spot that it has visited few months ago during its northern journey. The lake at Tormos ( 42°7'0" N - 0°40'60" W) is an important stop-over site for birds moving from the Mediterranean region to the Cantabric sea. 

New Publication on Plover survival in Mallorca

Garcia, P. J. and Tavecchia, G., 2018 Apparent survival and long-term population growth rate of the Kentish Plover Charadrius alexandrinus in Mallorca, Balearic Archipelago, Spain. Ardeola 65. 2-2. doi: http://dx.doi.org/10.13157/arla.65.1.2018.sc2

This was a collaboration between the GEDA and the GOB aiming to estimate the survival probability of Kentish Plovers in Mallroca using data from 1977. The main question was whether there was a trend in survival probability in the last twenty years.

https://commons.wikimedia.org/wiki/File:Charadrius_alexandrinus_0711.jpg

Abstract: During the last few decades, many breeding waders have been declining worldwide, probably due to the reduction of suitable coastal habitats. Diagnosis of population parameters has become increasingly important for the conservation of waders.
 We used capture-recapture information of 214 adult Kentish Plovers Charadrius alexandrinus, marked between 1977 and 2015 at two breeding areas in Mallorca, Spain, to assess any possible temporal trend in the survival probability. Mean adult survival probability was 0.756 ± 0.05 with no differences between the two areas. The sparseness of the data did not permit robust estimates of yearly survival. However, models with a temporal trend in survival probability were not retained. An age-structured population model including demographic stochasticity suggested a stable population (l = 1.024 ± 0.09). Perturbation analyses indicated that a 10% increase in mean breeding success (from 0.44 to 0.63), by reducing habitat loss or nest predation, would be sufficient to obtain positive population trajectories. 

New Publication on immune response in seabirds

Garnier, R., Ramos, R. Sanz-Aguilar, A., Poisbleau, M., Weimerskirch, H., Burthe, A., Tornos, J. and Boulinier, T., 2017. Interpreting ELISA analyses from wild animal samples: Somerecurrent issues and solutions Funcitonal Ecology, 31, 2255–2262 .DOI: 10.1111/1365-2435.12942

Abstract
1.Many studies in disease and ecological immunology rely on the use of assays that quantify the amount of specific antibodies (immunoglobulin) in samples. Enzymelinked immunosorbent assays (ELISAs) are increasingly used in ecology due to their availability for a broad array of antigens and the limited amount of sampling material they require. Two recurrent methodological issues are nevertheless faced by researchers: (1) the limited availability of immunological assays and reagents developed for non-model species, and (2) the statistical determination of the cut-off threshold used to distinguish individual samples that are likely to have or not to have antibodies against a specific antigen.

Photo: Victor París

2. Here, we outline two solutions to deal with these issues. First, we show that implementing two assays with differing detection methods can help validate the use of reagents, such as antibodies, in species different from their intended target. We illustrate this by comparing the quantification of  specific vaccinal antibodies against Newcastle disease virus (NDV) using two ELISA approaches in four seabird species (Cory’s shearwater, European shag, European storm petrel and Southern rockhopper penguin).
3. Second, we provide a simple way to determine from the distribution of ELISA values whether the assayed samples are likely to be made of a single group of individuals (likely negative) or of two groups of individuals (negative and positive). We illustrate the use of this approach with two independent datasets: NDV antibody levels following vaccination and anti-Borrelia antibody levels following natural exposure.
4. The practical implementation of these methodological approaches could provide a way to efficiently apply ELISAs and other immune-based assays to address questions in the growing fields of ecological immunology and disease ecology.