Beached bird surveys in Portugal 1990-1996

Between 1990 and 1996 a large proportion of the Portuguese coast was systematically surveyed for dead seabirds during the winter (October to March). About 5330 Km of beaches were walked during this period and 2660 dead seabirds were recorded. Razorbill Alca torda was the most common species, followed by Gannet Morus bassanus, Yellow-legged Gull Larus cachinnans and Lesser Black-backed Gull L. fuscus. Together, these species accounted for 73.7% of all corpses found. Most casualties were found in the central area of the Portuguese coast. Beaches in these regions face predominant northwesterly winds and are close to an important upwelling area which represents a potentially good feeding zone for seabirds. Oil contamination of the corpses was generally low, especially when compared with those recorded in similar surveys in some northern European countries. Deaths due to entanglement in fishing gear were significantly lower than those reported in previous surveys and they apparently no longer represent a major threat to seabirds in the Portuguese coast

The diet of a nocturnal pelagic predator, the Bulwer's petrel, across the lunar cycle

Existe informação suplementar disponível na versão online.The lunar cycle is believed to strongly influence the vertical distribution of many oceanic taxa, with implications for the foraging behaviour of nocturnal marine predators. Most studies to date testing lunar effects on foraging have focused on predator activity at-sea, with some birds and marine mammals demonstrating contrasting behavioural patterns, depending on the lunar-phase. However, to date no study has focused on how the lunar cycle might actually affect predator-prey interactions in the upper layers of the ocean. Here, we tested whether the diet of the predominantly nocturnal pelagic predator, the Bulwer's petrel (Bulweria bulwerii) would change throughout the lunar cycle, using molecular analysis to augment detection and taxonomic resolution of prey collected from stomach-contents. We found no evidence of dietary shifts in species composition or diversity, with Bulwer's petrel always consuming a wide range of mesopelagic species. Other co-variables potentially affecting light availability at-sea, such as percentage of cloud cover, did not confound our results. Moreover, many of the species found are thought not to reach the sea-surface. Our findings reveal that nocturnal predators are probably more specialized than previously assumed, irrespective of ambient-light, but also reveal deficiencies in our current understanding of species vertical distribution and predation-dynamics at-sea.Fundação para a Ciência e a Tecnologia (FCT); FEDERinfo:eu-repo/semantics/publishedVersio

IR, Raman and SERS spectra of 2-(methoxycarbonylmethylsulfanyl)-3,5-dinitrobenzene carboxylic acid

2-(Methoxycarbonylmethylsulfanyl)-3,5-dinitrobenzenecarboxylic acid was prepared by nucleophilic substitution. FT-IR and FT-Raman spectra of 2-(methoxycarbonylmethylsulfanyl)-3,5-dinitrobenzenecarboxylic acid were recorded and analyzed. Surface enhanced Raman scattering (SERS) spectrum was recorded on a silver colloid. The vibrational wavenumbers were computed by density functional theoretical (DFT) computations at the B3LYP/6-31G* level and they were found to be in good agreement with the experimental values. Significant metal-molecule interaction has been substantiated by the appearance of intense Ag-O mode in the SERS spectrum and this is indicative of the nearness of nitro and carbonyl group to the silver surface. SERS studies suggest a tilted orientation of the molecule at the metal surface

Lanthanopolyoxotungstates in silica nanoparticles: multi-wavelength photoluminescent core/shell materials

We thank Dr Marc Willinger and the RNME (National Electronic Microscopy Network, Portugal) for HRTEM images. Electronic supplementary information (ESI) available: FT-IR and FT-Raman spectra, additional HRTEM images and complementary photoluminescence spectra details, see DOI: 10.1039/b919691a.Photoluminescent lanthanopolyoxotungstate core/shell nanoparticles are prepared by the encapsulation of lanthanide-containing polyoxometalates (POMs) with amorphous silica shells. The preparation of morphological well-defined core/shell nanoparticles is achieved by the hydrolysis of tetraethoxysilane in the presence of POMs using a reverse microemulsion method. The POMs used are decatungstolanthanoates of [Ln(W(5)O(18))(2)](9-) type (Ln(III) = Eu, Gd and Tb). Photoluminescence studies show that there is efficient emission from the POM located inside the SiO(2) shells, through excitation paths that involve O --> Eu/Tb and O --> W ligand-to-metal charge transfer. It is also shown that the excitation of the POM containing europium(III) may be tuned towards longer wavelengths via an antenna effect, by coordination of an organic ligand such as 3-hydroxypicolinate. The POM/SiO(2) nanoparticles form stable suspensions in aqueous solution having the advantage of POM stabilization inside the core and the possibility of further surface grafting of chemical moieties via well known derivatization procedures for silica surfaces. These features together with the possibility of tuning the excitation wavelength by modifying the coordination sphere in the lanthanopolyoxometalate, make this strategy promising to develop a new class of optical bio-tags composed of silica nanobeads with multi-wavelength photoluminescent lanthanopolyoxometalate cores.FCT- POCI/QUI/58887/2004FCT- PTDC/ QUI/67712/2006FCT- SFRH/BD/30137/2006FCT- SFRH/BPD/14954/200

Seasonal variations in the diet and foraging behaviour of dunlins Calidris alpina in a South European estuary: improved feeding conditions for northward migrants

During the annual cycle, migratory waders may face strikingly different feeding conditions as they move between breeding areas and wintering grounds. Thus, it is of crucial importance that they rapidly adjust their behaviour and diet to benefit from peaks of prey abundance, in particular during migration, when they need to accumulate energy at a fast pace. In this study, we compared foraging behaviour and diet of wintering and northward migrating dunlins in the Tagus estuary, Portugal, by video-recording foraging birds and analysing their droppings. We also estimated energy intake rates and analysed variations in prey availability, including those that were active at the sediment surface. Wintering and northward migrating dunlins showed clearly different foraging behaviour and diet. In winter, birds predominantly adopted a tactile foraging technique (probing), mainly used to search for small buried bivalves, with some visual surface pecking to collect gastropods and crop bivalve siphons. Contrastingly, in spring dunlins generally used a visual foraging strategy, mostly to consume worms, but also bivalve siphons and shrimps. From winter to spring, we found a marked increase both in the biomass of invertebrate prey in the sediment and in the surface activity of worms and siphons. The combination of these two factors, together with the availability of shrimps in spring, most likely explains the changes in the diet and foraging behaviour of dunlins. Northward migrating birds took advantage from the improved feeding conditions in spring, achieving 65% higher energy intake rates as compared with wintering birds. Building on these results and on known daily activity budgets for this species, our results suggest that Tagus estuary provides high-quality feeding conditions for birds during their stopovers, enabling high fattening rates. These findings show that this large wetland plays a key role as a stopover site for migratory waders within the East Atlantic Flyway.This study was supported by Fundação para a Ciência e a Tecnologia (http://alfa.fct.mctes.pt/) through Project PTDC/MAR/119920/2010 and grants to RCM (SFRH/BD/44871/2008), TC (SFRH/BPD/46967/2008) and CDS (SFRH/BPD/64786/2009). JPG was under a research contract within project “Sustainable Use of Marine Resources - MARES” (CENTRO-07-ST24-FEDER-002033), co-financed by “Mais Centro” Regional Operational Programme (Centro Region) and European Regional Development Fund (ERDF). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.publishe

Global assessment of marine plastic exposure risk for oceanic birds

Plastic pollution is distributed patchily around the world’s oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species

Quantifying annual spatial consistency in chick-rearing seabirds to inform important site identification

Animal tracking has afforded insights into patterns of space use in numerous species and thereby informed area-based conservation planning. A crucial consideration when estimating spatial distributions from tracking data is whether the sample of tracked animals is representative of the wider population. However, it may also be important to track animals in multiple years to capture changes in distribution in response to varying environmental conditions. Using GPS-tracking data from 23 seabird species, we assessed the importance of multi-year sampling for identifying important sites for conservation during the chick-rearing period, when seabirds are most spatially constrained. We found a high degree of spatial overlap among distributions from different years in most species. Multi-year sampling often captured a significantly higher portion of reference distributions (based on all data for a population) than sampling in a single year. However, we estimated that data from a single year would on average miss only 5 % less of the full distribution of a population compared to equal-sized samples collected across three years (min: −0.3 %, max: 17.7 %, n = 23). Our results suggest a key consideration for identifying important sites from tracking data is whether enough individuals were tracked to provide a representative estimate of the population distribution during the sampling period, rather than that tracking necessarily take place in multiple years. By providing an unprecedented multi-species perspective on annual spatial consistency, this work has relevance for the application of tracking data to informing the conservation of seabirds

Global assessment of marine plastic exposure risk for oceanic birds

Plastic pollution is distributed patchily around the world’s oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species