Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Factors affecting plumage oiling levels in a Kentish Plover Charadrius alexandrinus population after a major oil spill

100%

Dominiguez J., Vidal M.

Acta Ornithologica

2009

tom 44

nr 2

The oil tanker Prestige, with a 77 000-tonne cargo of heavy fuel oil, was badly damaged on 13 November 2002 off the Galician coast (NW Spain), where it leaked about 63 000 tonnes of oil. During the winter of 2002 and spring of 2003, we studied the degree of oil contamination in the plumage of the Kentish Plover Charadrius alexandrinus. Using the Generalized Estimated Equations (GEE), we evaluated the hypothesis that the presence of oiled birds in the breeding period could be influenced by 1) the location of the beach (estuarine versus non-estuarine), 2) the presence of an intertidal area in the lagoon associated with the beach, 3) the distance from the initial spill location and 4) the month. The worst affected body parts were the abdomen, and, to a lesser extent, the breast. The location of the beach was the only predictor included in the final model. The beaches with the highest average scores of oiled birds were those located on the non-estuarine coast. The other two predictors with significant parameters in the univariate analysis were the distance from the initial spill location and the month.

Using remote sensing data to model European wild rabbit (Oryctolagus cuniculus) occurrence in a highly fragmented landscape in northwestern Spain

80%

Tapia L., Dominguez J., Regos A., Vidal M.

Acta Theriologica

2014

tom 59

nr 2

We model the occurrence of European wild rabbit in fragmented environments in a mountainous area of northwestern Spain (Gerês–Xurés Biosphere Reserve). We carried out a field survey by sampling the presence/absence of pellets in 237 plots (100 × 100 m) selected at random below an altitude of 800 m. For modelling purposes, we considered eight predictors related to vegetation, topography, human influence and heterogeneity. We obtained vegetation and ecological predictors from land use/land cover maps derived from Landsat Enhanced Thematic Mapper Plus images (acquired at the same time as the field data) and calculated vegetation indices by using a supervised classification method. We obtained topographical predictors from a Global Digital Elevation Model (GDEM) and used a generalized linear model to describe the occurrence of the European wild rabbit. The overall accuracy of the Landsat-derived map in Baixa Limia was 87.51 %, and the kappa coefficient was 0.85. The most parsimonious model included “grassland and crops”, “mean slope”, “distance to roads”, “urban settlements” and “ecotone scrubland-forest”. Five predictors were consequential, three of them with a positive sign for the presence of the species (scrub, urban settlements and ecotone scrubland-forest) and two with a negative sign (mean slope and distance to roads). The information on habitat requirements of European wild rabbit in the area provides a good framework for determining the habitat requirements of this keystone species in mountainous ecosystems in northwestern Iberian Peninsula.

Ograniczanie wyników

1 Acta Ornithologica

1 Acta Theriologica

2 Vidal M.

1 Dominguez J.

1 Dominiguez J.

1 Regos A.

1 Tapia L.

1 2014

1 2009

Wyniki wyszukiwania

Factors affecting plumage oiling levels in a Kentish Plover Charadrius alexandrinus population after a major oil spill

Using remote sensing data to model European wild rabbit (Oryctolagus cuniculus) occurrence in a highly fragmented landscape in northwestern Spain