Central-place Foraging in an Arctic Seabird Provides Evidence for Storer-Ashmole's Halo

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Resultados preliminares sobre la ecología trófica de la pardela balear, Puffinus mauretanicus a partír de aves marcadas con Data-Loggers

A data logger devised and manufactured by our research team in order to study the homing routes of carrier pigeons was subsequently modified to study the homing behaviour and foraging strategies of breeding marine birds. Recent versions of the data logger, equipped with a flight sensor and depth meter or saltwater switch, were used in a study of the foraging strategies of chick-rearing Balearic shearwaters (Puffinus mauretanicus) in the framework of the project LIFE-Puffinus financed by the Balearic Government and the EU. Due to low recapture rates (only 3 out of 6 tagged birds were recovered), only preliminary data from a small sample are available. Data loggers have recorded data on the pattern of nest attendance (including departure time to foraging trips and return time) and the diurnal pattern of flight and dive activity (including depth and duration of dives). Despite the small sample size, the results show that our data loggers can successfully be applied to the study of the breeding biology and foraging ecology-including the diving pattern-of Balearic shearwaters and similar species.Un dispositivo electrónico diseñado y producido por nuestro equipo de investigación con la finalidad de estudiar las rutas de vuelo de palomas mensajeras ha sido adaptado al uso en investigación de la conducta de nidificación y estrategias de alimentación en aves marinas. Versiones mejoradas del aparato, equipado con un sensor de vuelo, y un profundímetro (o bien un sensor de agua marina) se han utilizado para el estudio de las estrategias de alimentación de individuos reproductores de la pardela balear (Puffinus mauretanicus), en el marco del proyecto LIFEPuffinus financiado por el Govern de les Illes Balears y la UE. Disponemos únicamente de datos preliminares, debido al pequeño tamaño de la muestra, ya que sólo se recuperaron tres de los seis aparatos colocados sobre las aves. Los data-loggers han proporcionado información sobre el modelo de permanencia en el nido (incluyendo los horarios de salidas y entradas ), la distribución diaria de las actividades de vuelo y buceo, así como la profundidad y duración de las zambullidas. A pesar del pequeño tamaño de la muestra, nuestros resultados sugieren que este tipo de data logres puede utilizarse en estudios de conducta de nidificación y alimentación de aves de la talla de la pardela balear, incluyendo el estudio del modelo de buceo

Annual variation in great skua diets: the importance of commercial fisheries and predation on seabirds revealed by combining dietary analyses

This study combines conventional dietary assessment with stable isotope techniques to describe Great Skua (Stercorarius skua) diet. Stable carbon and nitrogen isotope ratios in feathers of Great Skua chicks collected over three years were analyzed in conjunction with pellet and regurgitate collections. A significant drop in trophic status was detected in 1997, which likely resulted from an increase in herring and mackerel in the diet. These items were almost certainly obtained from a commercial trawler, as evidenced by a significant drop in territorial attendance during the ship's absence. Feathers yielded significantly different δ13C values among years, and part of this may have been related to a period of enhanced phytoplankton growth during 1996. A combined approach, such as the one described here, is likely to become increasingly useful in elucidating the diets of polyphagous birds

Partitioning of diving effort in foraging trips of northern gannets

Many species of seabirds are known to undertake foraging trips that vary in duration, lasting from a few hours up to several days. However, the important question of how individuals allocate their time during foraging trips of different durations has received relatively little attention until recently. Using activity loggers, we examined the foraging behavior of chick-rearing northern gannets, Morus bassanus (L., 1758), during trips of different durations, and tested predictions concerning how foraging activity varies across trips. There was no evidence of a relationship between dive frequency during the first 3 h of a trip and trip duration, suggesting that the decision to continue on a longer trip was not affected by an adult's initial rate of encounter with prey. Flight constituted approximately 50% of total trip time, and the dive rate of birds per daylight hour was apparently unaffected by trip duration. Birds dived at similar rates on the outward and return sections of their foraging trips, which suggests that they may have been "topping up" on food on their return. Overall our results suggest that, unlike other pelagic seabirds, northern gannets at the Bass Rock do not adjust their individual foraging strategies among trips of different durations

iTalian RegIstry of doUble inner branch stent graft for arch PatHology (the TRIUmPH Registry)

Objective: The objective of this study was to assess early and midterm results after endovascular aortic arch repair using a double inner branch stent graft (DIBSG) in patients with aortic arch aneurysm or dissection unfit for open surgery. Methods: Between 2012 and 2018, there were 24 patients with aortic arch disease who were treated with a single model of a DIBSG (Terumo Aortic, Glasgow, United Kingdom) in nine Italian cardiovascular centers. We investigated technical success, mortality, occurrence of major complications, and need for reintervention in a multicenter, nonrandomized, retrospective fashion. Results: The in-hospital mortality rate was 16.7%. Cerebrovascular events occurred in 25% of patients and major strokes in 12.5%. Two patients experienced a retrograde dissection (8.3%), whereas none reported any type I or type III endoleak. During a mean follow-up of 18 months (range, 1-60 months), one patient died of a nonaortic cause and one reported a nonarch-related major stroke. No late secondary intervention was needed during the follow-up. Excluding from the analysis the first six patients treated until 2014 as part of the learning curve, in-hospital mortality, major stroke, and retrograde dissection rates were 11.1%, 11.1%, and 5.6%, respectively. Conclusions: Endovascular aortic arch repair using this model of DIBSG is feasible, and results are acceptable for a new technique in a high-risk subset of patients. Operative mortality suffers the effect of a learning curve, whereas midterm aorta-related survival is promising. Endovascular repair of aortic arch disease with a DIBSG should always be considered to give high-risk patients a chance of repair. Large-scale studies are needed to assess the long-term durability of this technique