8 documents found, page 1 of 1
Assessment of harbour porpoise bycatch along the Portuguese and Galician Coast:...
Torres-Pereira, Andreia; Araújo, Hélder; Monteiro, Silvia Silva; Ferreira, Marisa; Bastos-Santos, Jorge; Sá, Sara; Nicolau, Lídia; Marçalo, AnaThe Iberian harbour porpoise population is small and fisheries bycatch has been described as one of its most important threats. Data on harbour porpoise strandings collected by the Portuguese and Galician stranding networks between 2000 and 2020 are indicative of a recent mortality increase in the western Iberian coast (particularly in northern Portugal). Overall, in Portugal and Galicia, individuals stranded d...
Seabird abundance and distribution off western iberian waters estimated through...
Araújo, Hélder; Rodrigues, Pedro; Bastos Santos, Jorge; Ferreira, Marisa; Pereira, Andreia; Martinez Cedeira, Jose; Vingada, José; Eira, CatarinaWestern Iberian waters are important migratory flyways, stopover sites, and wintering areas for several of the world’s seabird species. To describe seabird species composition, distribution, and abundance in these waters, we performed six aerial surveys in September and/or October of each year, 2010–2015, covering 74 840 km2. Using line transect methodology, 27 396 seabird sightings from 17 taxonomic groups wer...
Balearic shearwater and northern gannet bycatch risk assessment in Portuguese C...
Araújo, Hélder; Correia Rodrigues, Pedro; Debru, Philippe; Ferreira, Marisa; Vingada, José; Eira, CatarinaEven though incidental captures in fisheries are one of the major threats to seabirds, bycatch has been difficult to quantify and specific risk areas are rarely identified. The present study evaluates the potential fisheries bycatch effect on two of the most emblematic seabird species wintering off continental Portugal, the critically endangered Balearic Shearwater and Northern Gannet. Information was collected...
Monitoring Abundance and Distribution of Northern Gannets Morus bassanus in Wes...
Araújo, Hélder; Rodrigues, Pedro; Bastos-Santos, Jorge; Ferreira, Marisa; Pereira, Andreia; Martínez-Cedeira, José; Vingada, José; Eira, CatarinaSeveral North Atlantic breeding seabirds, such as the Northern Gannet Morus bassanus, use Western Iberian Waters for wintering and migration. In this study, we aimed at producing absolute population estimates of post-breeding Gannets and evaluating the importance of the study area within the species’ migration range. We performed six aerial surveys in September and/or October each year between 2010 and 2015, co...
Striped dolphins as trace element biomonitoring tools in oceanic waters: accoun...
Monteiro, Sílvia S.; Bozzetti, Márcia; Torres, Jordi; Tavares, Ana S.; Ferreira, Marisa; Pereira, Andreia T.; Sá, Sara; Araújo, HélderIn Europe, monitoring contaminant concentrations and their effects in the marine environment is required under the Marine Strategy Framework Directive (MSFD, 2008/56/EC). The striped dolphin (Stenella coeruleoalba) is the most abundant small cetacean species in Portuguese oceanic waters, representing a potential biomonitoring tool of contaminant levels in offshore waters. Concentrations of nine trace elements w...
Wireless Capsule Endoscope Location and a Robotic Validation Experiment
Figueiredo, Isabel N.; Pinto, Luís; Perdigoto, Luís; Oliveira, Marina; Araújo, Hélder; Figueiredo, Pedro N.We present results concerning the validation of a novel approach for wireless capsule endoscope localization, using as ground truth a simulated biological/mechanical environment experiment. The approach relies essentially on image-based methods. It involves a hybrid multi-scale affine and elastic image registration procedure which is afterwards appropriately complemented with calibration and visual odometry tec...
The importance of Portuguese Continental Shelf Waters to Balearic Shearwaters r...
Araújo, Hélder; Bastos-Santos, Jorge; Rodrigues, Pedro Correia; Ferreira, Marisa; Pereira, Andreia; Henriques, Ana Catarina; Monteiro, Sílvia S.The Balearic shearwater Puffinus mauretanicus is one of the most threatened seabirds in the world. To evaluate the abundance and distribution of Balearic Shearwaters in Portuguese Continental Shelf Waters, during the post-breeding period when migrating birds are outside the Mediterranean Sea, we conducted 5 aerial surveys between 2010 and 2014 (21 survey days covering 62,716 km2). Following a line transect meth...
Cetacean occurrence, habitat preferences and potential for cetacean-fishery int...
Goetz, Sabine; Read, Fiona L.; Ferreira, Marisa; Martínez Portela, Julio; Begoña Santos, Maria; Vingada, José; Siebert, Ursula; Marçalo, AnaIberian Atlantic waters are heavily exploited by Spanish and Portuguese fisheries. Overlaps between fishery target species and cetacean diet, and between fishing grounds and cetacean foraging areas, can lead to cetacean–fishery interactions including bycatch mortality of cetaceans. The present study assesses cetacean distribution, habitat preferences and hotspots for cetacean–fishery interactions by using a coo...