Decadal Trends in Abundance, Size and Condition of Antarctic Toothfish in McMurdo Sound, Antarctica, 1972-2010

We report analyses of a dataset spanning 38 years of near-annual fishing for Antarctic toothfish Dissostichus mawsoni, using a vertical setline through the fast ice of McMurdo Sound, Antarctica, 1972-2010. This constitutes one of the longest biological time series in the Southern Ocean, and certainly the longest for any fish. Fish total length, condition and catch per unit effort (CPUE) were derived from the more than 5500 fish caught. Contrary to expectation, length-frequency was dominated by fish in the upper half of the industrial catch. The discrepancy may be due to biases in the sampling capabilities of vertical (this study) versus benthic (horizontal) fishing gear (industry long lines), related to the fact that only large Antarctic toothfish (more than 100 cm TL) are neutrally buoyant and occur in the water column. Fish length and condition increased from the early 1970s to the early 1990s and then decreased, related to sea ice cover, with lags of 8 months to 5 years, and may ultimately be related to the fishery (which targets large fish) and changes in the Southern Annular Mode through effects on toothfish main prey, Antarctic silverfish Pleuragramma antarcticum. CPUE was constant through 2001 and then decreased dramatically, likely related to the industrial fishery, which began in 1996 and which concentrates effort over the Ross Sea slope, where tagged McMurdo fish have been found. Due to limited prey choices and, therefore, close coupling among mesopredators of the Ross Sea, Antarctic toothfish included, the fishery may be altering the trophic structure of the Ross Sea

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Annual prey consumption of the Common Murre, a Dominant Seabird in the California Current

In this project, researchers compiled information on Common Murre (Uria aalge) population size, diet, field metabolic rate, prey energy densities and assimilation efficiency to estimate the bird’s annual prey consumption between Cape Blanco, Ore. and Point Conception, California

Annual prey consumption of the Common Murre, a Dominant Seabird in the California Current

In this project, researchers compiled information on Common Murre (Uria aalge) population size, diet, field metabolic rate, prey energy densities and assimilation efficiency to estimate the bird’s annual prey consumption between Cape Blanco, Ore. and Point Conception, California

Population Studies of Tidal Marsh Breeding Birds at Rush Ranch: A Synthesis

Rush Ranch, with the largest contiguous area of fully-tidal marsh remaining in northern Suisun Bay, is critical habitat for a number of endemic bird species that breed in brackish tidal marsh. Despite the abundance of non-native invasive plants (particularly perennial pepperweed, Lepidium latifolium) and altered hydrology, it is the best remaining representative in Solano County of the tidal marsh that once covered more than 27,000 ha (67,000 acres) in Suisun Bay. This paper presents a synthesis of bird population studies conducted at Rush Ranch since the late 1970s, concentrating on California clapper rail (Rallus longirostris obsoletus), California black rail (Laterallus jamaicensis coturniculus), Suisun song sparrow (Melospiza melodia maxillaris), common yellowthroat (Geothlypis trichas), and marsh wren (Cistothorus palustris). These studies indicate declines in clapper rail abundance, when we compared the past 8 years to surveys conducted 10 to 25 years ago. However, black rails appear to be increasing at Rush Ranch, and overall in Suisun Bay. Nest monitoring of reproductive attempts by song sparrows conducted between 1996 and 2005 indicates low overall nest survival rates, mainly from high predation rates, but also great year-to-year variability. Low nest survival rates of tidal marsh song sparrows observed at Rush Ranch appear to be too low to sustain populations, and such low rates are consistent with the apparent population declines observed for this subspecies at Rush Ranch. Nest survival and other components of reproductive success of tidal marsh birds should be monitored in the future to provide information on ecosystem condition and population health, as well as the response of these species to management, including control of non-native plant species.

Population Studies of Tidal Marsh Breeding Birds at Rush Ranch: A Synthesis

Rush Ranch, with the largest contiguous area of fully-tidal marsh remaining in northern Suisun Bay, is critical habitat for a number of endemic bird species that breed in brackish tidal marsh. Despite the abundance of non-native invasive plants (particularly perennial pepperweed, Lepidium latifolium) and altered hydrology, it is the best remaining representative in Solano County of the tidal marsh that once covered more than 27,000 ha (67,000 acres) in Suisun Bay. This paper presents a synthesis of bird population studies conducted at Rush Ranch since the late 1970s, concentrating on California clapper rail (Rallus longirostris obsoletus), California black rail (Laterallus jamaicensis coturniculus), Suisun song sparrow (Melospiza melodia maxillaris), common yellowthroat (Geothlypis trichas), and marsh wren (Cistothorus palustris). These studies indicate declines in clapper rail abundance, when we compared the past 8 years to surveys conducted 10 to 25 years ago. However, black rails appear to be increasing at Rush Ranch, and overall in Suisun Bay. Nest monitoring of reproductive attempts by song sparrows conducted between 1996 and 2005 indicates low overall nest survival rates, mainly from high predation rates, but also great year-to-year variability. Low nest survival rates of tidal marsh song sparrows observed at Rush Ranch appear to be too low to sustain populations, and such low rates are consistent with the apparent population declines observed for this subspecies at Rush Ranch. Nest survival and other components of reproductive success of tidal marsh birds should be monitored in the future to provide information on ecosystem condition and population health, as well as the response of these species to management, including control of non-native plant species.

Annual prey consumption of a dominant seabird, Common Murre, in the California Current

We collated information on population size, diet composition, energy requirements, energy densities of prey species, and assimilation efficiency from the literature to estimate annual prey consumption by Common Murres (Uria aalge) between Cape Blanco, Oregon and Point Conception, California in 2004. We estimated that the population consumed approximately 242,250 metric tons of prey, including 70,500 metric tons consumed by breeding adults, 51,920 metric tons consumed by nonbreeding adults and subadults during the breeding season (March-August), 119,620 metric tons consumed by all birds during the wintering period (September –February), and 214 metric tons consumed by dependent chicks prior to leaving breeding colonies. Pacific hake (Merluccius productus) and market squid (Loligo opalescens) each made up over 20% of annual prey consumption. Other species making up at least 10% of annual consumption included shiner surfperch (Cymatogaster aggregata), northern anchovy (Engraulis mordax), and rockfish (Sebastes spp.). Chick diet was dominated by anchovy/sardine (Sardinops sagax; 63%), rockfish (21%), and smelt (Osmeridae spp.; 7%). Understanding these prey requirements is important for understanding the dynamics of predator and prey populations and for effective management of ocean resources

Annual prey consumption of a dominant seabird, Common Murre, in the California Current

We collated information on population size, diet composition, energy requirements, energy densities of prey species, and assimilation efficiency from the literature to estimate annual prey consumption by Common Murres (Uria aalge) between Cape Blanco, Oregon and Point Conception, California in 2004. We estimated that the population consumed approximately 242,250 metric tons of prey, including 70,500 metric tons consumed by breeding adults, 51,920 metric tons consumed by nonbreeding adults and subadults during the breeding season (March-August), 119,620 metric tons consumed by all birds during the wintering period (September –February), and 214 metric tons consumed by dependent chicks prior to leaving breeding colonies. Pacific hake (Merluccius productus) and market squid (Loligo opalescens) each made up over 20% of annual prey consumption. Other species making up at least 10% of annual consumption included shiner surfperch (Cymatogaster aggregata), northern anchovy (Engraulis mordax), and rockfish (Sebastes spp.). Chick diet was dominated by anchovy/sardine (Sardinops sagax; 63%), rockfish (21%), and smelt (Osmeridae spp.; 7%). Understanding these prey requirements is important for understanding the dynamics of predator and prey populations and for effective management of ocean resources