21 research outputs found
Flight and foraging patterns of lesser black-backed gulls and Northern gannets in the southern North Sea
The study focuses on the foraging ecology of two common seabird species of the southern North Sea, lesser black-backed gulls and northern gannets. The spatiotemporal patterns were considered in light of offshore wind farms, representing a recent anthropogenic pressure on the birds' foraging and space use. Flight and foraging patterns of both species were recorded by attaching small GPS data loggers on breeding birds at different German North Sea Islands. Their foraging patterns differed among the six studied breeding colonies and between the sexes, and also indicated a large amount of individual specialisation in foraging behaviour. The vertical flight distribution of lesser black-backed gulls showed that birds flew in the critical heights of the rotor swept areas of offshore wind farms to a certain extent, and thus were likely to collide with offshore turbines, expecially during bad weather conditions. Northern gannets, which are rather inflexible flyers with poor flight manoeuvrability compared to the gulls, largely avoided the offshore wind farm areas, and only crossed those areas where turbines were not installed yet
Flug- und Nahrungssuchmuster von Heringsmöwen und Basstölpeln in der sĂŒdlichen Nordsee
The study focuses on the foraging ecology of two common seabird species of the southern North Sea, lesser black-backed gulls and northern gannets. The spatiotemporal patterns were considered in light of offshore wind farms, representing a recent anthropogenic pressure on the birds' foraging and space use. Flight and foraging patterns of both species were recorded by attaching small GPS data loggers on breeding birds at different German North Sea Islands. Their foraging patterns differed among the six studied breeding colonies and between the sexes, and also indicated a large amount of individual specialisation in foraging behaviour.
The vertical flight distribution of lesser black-backed gulls showed that birds flew in the critical heights of the rotor swept areas of offshore wind farms to a certain extent, and thus were likely to collide with offshore turbines, expecially during bad weather conditions.
Northern gannets, which are rather inflexible flyers with poor flight manoeuvrability compared to the gulls, largely avoided the offshore wind farm areas, and only crossed those areas where turbines were not installed yet
Peri-operative red blood cell transfusion in neonates and infants: NEonate and Children audiT of Anaesthesia pRactice IN Europe: A prospective European multicentre observational study
BACKGROUND: Little is known about current clinical practice concerning peri-operative red blood cell transfusion in neonates and small infants. Guidelines suggest transfusions based on haemoglobin thresholds ranging from 8.5 to 12âgâdl-1, distinguishing between children from birth to day 7 (week 1), from day 8 to day 14 (week 2) or from day 15 (â„week 3) onwards. OBJECTIVE: To observe peri-operative red blood cell transfusion practice according to guidelines in relation to patient outcome. DESIGN: A multicentre observational study. SETTING: The NEonate-Children sTudy of Anaesthesia pRactice IN Europe (NECTARINE) trial recruited patients up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures from 165 centres in 31 European countries between March 2016 and January 2017. PATIENTS: The data included 5609 patients undergoing 6542 procedures. Inclusion criteria was a peri-operative red blood cell transfusion. MAIN OUTCOME MEASURES: The primary endpoint was the haemoglobin level triggering a transfusion for neonates in week 1, week 2 and week 3. Secondary endpoints were transfusion volumes, 'delta haemoglobin' (preprocedure - transfusion-triggering) and 30-day and 90-day morbidity and mortality. RESULTS: Peri-operative red blood cell transfusions were recorded during 447 procedures (6.9%). The median haemoglobin levels triggering a transfusion were 9.6 [IQR 8.7 to 10.9] gâdl-1 for neonates in week 1, 9.6 [7.7 to 10.4] gâdl-1 in week 2 and 8.0 [7.3 to 9.0] gâdl-1 in week 3. The median transfusion volume was 17.1 [11.1 to 26.4] mlâkg-1 with a median delta haemoglobin of 1.8 [0.0 to 3.6] gâdl-1. Thirty-day morbidity was 47.8% with an overall mortality of 11.3%. CONCLUSIONS: Results indicate lower transfusion-triggering haemoglobin thresholds in clinical practice than suggested by current guidelines. The high morbidity and mortality of this NECTARINE sub-cohort calls for investigative action and evidence-based guidelines addressing peri-operative red blood cell transfusions strategies. TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02350348
The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance
INTRODUCTION
Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic.
RATIONALE
We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs).
RESULTS
Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants.
CONCLUSION
Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century
Varying foraging patterns in response to competition? A multicolony approach in a generalist seabird
Reducing resource competition is a crucial requirement for colonial seabirds to ensure adequate selfâ and chickâprovisioning during breeding season. Spatial segregation is a common avoidance strategy among and within species from neighboring breeding colonies. We determined whether the foraging behaviors of incubating lesser blackâbacked gulls (Larus fuscus) differed between six colonies varying in size and distance to mainland, and whether any differences could be related to the foraging habitats visited. Seventyânine incubating individuals from six study colonies along the German North Sea coast were equipped with GPS data loggers in multiple years. Dietary information was gained by sampling food pellets, and blood samples were taken for stable isotope analyses. Foraging patterns clearly differed among and within colonies. Foraging range increased with increasing colony size and decreased with increasing colony distance from the mainland, although the latter might be due to the inclusion of the only offshore colony. Gulls from larger colonies with consequently greater densityâdependent competition were more likely to forage at land instead of at sea. The diets of the gulls from the colonies furthest from each other differed, while the diets from the other colonies overlapped with each other. The spatial segregation and dietary similarities suggest that lesser blackâbacked gulls foraged at different sites and utilized two main habitat types, although these were similar across foraging areas for all colonies except the single offshore island. The avoidance of intraspecific competition results in colonyâspecific foraging patterns, potentially causing more intensive utilization of terrestrial foraging sites, which may offer more predictable and easily available foraging compared with the marine environment
Decreasing ÎŽ13C and ÎŽ15N values in four coastal species at different trophic levels indicate a fundamental food-web shift in the southern North and Baltic Seas between 1988 and 2016
Marine ecosystems are exposed to increasing
human pressures and climatic change worldwide. It has
therefore become essential to describe ecosystem statuses
with respect to multinational protection schemes,
often necessitating long-term monitoring programmes.
Changes in the food-web structure, which can be monitored
via stable isotope measurements, represent an
important descriptor of the status of marine ecosystems.
We investigated long-term changes (29 years) in isotopic
values (ÎŽ13C and ÎŽ15N) in four indicative organisms
at different trophic levels in the southern North and
Baltic Seas: bladderwrack (Fucus vesiculosus), blue
mussel (Mytilus ssp.), eelpout (Zoarces viviparus), and
herring gull (Larus argentatus). Time series analyses
using generalised additive models revealed largely consistent
declines in ÎŽ13C and ÎŽ15N throughout all trophic
levels of the coastal food web at all study sites, indicating
a clear change in these coastal regions from 1988 to
2016. There were no clear long-term patterns in egg
biometrics for herring gulls, except for a consistent
increase in eggshell thickness. The declines in stable
isotope values were in line with the results of previous
long-term studies of single higher-trophic-level species,
which suggested that the noted changes were mainly
caused by altered foraging patterns of the studied species.
The current results demonstrate that declines in
ÎŽ13Cand ÎŽ15N have occurred throughout the whole food
web, not just in particular species. We discuss the possible
reasons for the decrease in stable isotope values,
including decreasing eutrophication and an increase in
terrestrial carbon source
Terrestrial and Marine Foraging Strategies of an Opportunistic Seabird Species Breeding in the Wadden Sea
<div><p>Lesser black-backed gulls <i>Larus fuscus</i> are considered to be mainly pelagic. We assessed the importance of different landscape elements (open sea, tidal flats and inland) by comparing marine and terrestrial foraging behaviours in lesser black-backed gulls breeding along the coast of the southern North Sea. We attached GPS data loggers to eight incubating birds and collected information on diet and habitat use. The loggers recorded data for 10â19 days to allow flight-path reconstruction. Lesser black-backed gulls foraged in both offshore and inland areas, but rarely on tidal flats. Targets and directions were similar among all eight individuals. Foraging trips (n = 108) lasted 0.5â26.4 h (mean 8.7 h), and ranges varied from 3.0â79.9 km (mean 30.9 km). The total distance travelled per foraging trip ranged from 7.5â333.6 km (mean 97.9 km). Trips out to sea were significantly more variable in all parameters than inland trips. Presence in inland areas was closely associated with daylight, whereas trips to sea occurred at day and night, but mostly at night. The most common items in pellets were grass (48%), insects (38%), fish (28%), litter (26%) and earthworms (20%). There was a significant relationship between the carbon and nitrogen isotope signals in blood and the proportional time each individual spent foraging at sea/land. On land, gulls preferentially foraged on bare ground, with significantly higher use of potato fields and significantly less use of grassland. The flight patterns of lesser black-backed gulls at sea overlapped with fishing-vessel distribution, including small beam trawlers fishing for shrimps in coastal waters close to the colony and large beam-trawlers fishing for flatfish at greater distances. Our data show that individuals made intensive use of the anthropogenic landscape and seascape, indicating that lesser black-backed gulls are not a predominantly marine species during the incubation period.</p></div
ÎŽ<sup>13</sup>C and ÎŽ<sup>15</sup>N values from red blood cell and blood plasma in relation to the proportion of foraging spent at sea for the six lesser black-backed gulls for which information was available.
<p>One red blood cell and one blood plasma value are given for each individual. Bold lines: regression lines of linear model; dotted lines: 95% confidence interval.</p
First passage time analysis of foraging behaviour of lesser black-backed gulls nesting on Spiekeroog in 2010.
<p>First passage time analysis of foraging behaviour of lesser black-backed gulls nesting on Spiekeroog in 2010.</p
Frequency distribution of (a) foraging-trip duration, (b) foraging range, and (c) total distance travelled for foraging trips targeting the sea (blue bars) and land (grey bars).
<p>Bars show the mean percentage over all eight individuals, and the vertical lines represent the standard error.</p