RESUMO
Understanding the sensory ecology of species is vital if we are to predict how they will function in a changing environment. Visual cues are fundamentally important for many predators when detecting and capturing prey. However, many marine areas have become more turbid through processes influenced by climate change, potentially affecting the ability of marine predators to detect prey. We performed the first study that directly relates a pelagic seabird species's foraging behaviour to oceanic turbidity. We collected biologging data from 79 foraging trips and 5472 dives of a visually dependent, pursuit-diving seabird, the Manx shearwater (Puffinus puffinus). Foraging behaviour was modelled against environmental variables affecting underwater visibility, including water turbidity, cloud cover and solar angle. Shearwaters were more likely to initiate area-restricted search and foraging dives in clearer waters. Underwater visibility also strongly predicted dive rate and depth, suggesting that fine-scale prey capture was constrained by the detectability of prey underwater. Our novel use of dynamic descriptors of underwater visibility suggests that visual cues are vital for underwater foraging. Our data indicate that climate change could negatively impact seabird populations by making prey more difficult to detect, compounded by the widely reported effects of reduced prey populations.
Assuntos
Mergulho , Animais , Aves , Ecologia , Comportamento Alimentar , Comportamento PredatórioRESUMO
Haematological analyses can reveal the physiological condition of birds, which are known to efficiently disguise symptoms of stress and disease. However, the interpretation of such analyses requires species-specific baseline data, which are lacking for most free-living seabird species. We provide baseline reference data for several haematological parameters in northern gannets (Morus bassanus) and combine this with telemetry and dietary data to understand the links between haematological condition and foraging behaviour. Blood samples were collected from breeding northern gannets in July 2017 (n = 15) and 2018 (n = 28), which were also equipped with GPS tags. Smears were prepared for performing blood cell counts, including immature erythrocyte and microcyte percentages, total and differential leucocyte counts, heterophil : lymphocyte (H : L) ratio and total thrombocyte count; the remaining blood was used for stable isotope analysis and foraging behaviours were inferred from the recovered tag data. Blood cell counts revealed that the sampled birds were highly stressed and some showed an immune response, evident from the abnormal leucocyte counts and the H : L ratio. There were no sex-related differences in haematological parameters or diet, in contrast to foraging parameters where females undertook longer trips than males and spent proportionately more time in search behaviours. The percentage time spent actively foraging was weakly negatively correlated with the percentage of eosinophils. While there was no direct link between haematological condition and diet, one bird feeding at a relatively low trophic level undertook exceptionally short foraging trips and showed abnormal blood cell counts. This suggests a link between haematological condition and foraging ecology that can be employed in assessing seabird health.
RESUMO
Ongoing monitoring of the availability of hospital critical care resources is necessary to assure patients in the emergency medical services (EMS) system reach appropriate care. In this densely populated area Multnomah County, Oregon, ambulances have been diverted by radio from several hospitals before finding one that would accept the patient. Dispatch centers and base-stations had no reliable method to monitor the availability of hospital resources. Data were not available for use in establishing policy. In response, this community developed an on-line, computerized system known as Computerized Hospital On-Line Resources Allocation Link (CHORAL) that visually displays the resource status of all hospitals to the 911 center, base station, and participating hospitals. A change of status requires simple keystrokes for entry into the computer which in turn transmitted automatically to all other CHORAL computers. Six patient care resources are monitored: Adult Ward (AW); Computerized Axial Tomography Scan (CT); Critical Care (CC); Labor and Delivery (LD); Pediatric (PEDS); and Psychiatric Secure Beds (PSB). Paramedics use protocol to determine if a particular patient fits one of these categories. Availability is relayed to paramedics by the 911 center and the base-station. During the first three months of system operation, there were 337 diversions representing 4,527 hours among 10 of the 12 participating hospitals. The most common resource resulting in diversion was PSB, which was unavailable for 2,195 hours (48.5%). Unavailability of CT resulted in the lowest number of diversions (1.3%, 60.3 hours).(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Redes de Comunicação de Computadores , Sistemas de Comunicação entre Serviços de Emergência , Serviços Médicos de Emergência/organização & administração , Ambulâncias , Alocação de Recursos para a Atenção à Saúde , Unidades Hospitalares , Humanos , Fatores de Tempo , Transporte de PacientesRESUMO
Review of a large renal transplant experience revealed a 17.3% incidence of posttransplant erythrocytosis. The influence of kidney source, pretransplant hematocrit, duration of pretransplant dialysis, renal transplant function, acute rejection, transplant renal artery stenosis, urinary tract obstruction, smoking, diabetes, retention of native kidneys, splenectomy, parathyroidectomy, immunosuppression, hypertension, and liver enzyme abnormalities on the development of erythrocytosis in 53 recipients was determined. Comparison was made with 49 control recipients matched for kidney function, time after grafting, age, and sex. Erythrocytosis occurred 3 to 90 months after transplantation and persisted for 1 to over 84 months. Risk factors for the development of erythrocytosis were smoking, diabetes, and a rejection free course. In contradistinction to previous smaller series, erythrocytosis occurred in patients with good renal function (serum creatinine 1.62 +/- 0.43 mg/dl) without prominence of graft rejection, transplant artery stenosis or obstruction. Despite therapeutic phlebotomy, 11 thromboembolic events occurred in 10 of the 53 patients with erythrocytosis, but in none of the controls (P less than 0.001). The high incidence of erythrocytosis following renal transplantation and the risk of associated thromboembolic events should encourage awareness and controlled evaluation of therapeutic modalities.