Decomposition in differing snow regimes in high Arctic Svalbard

Rapidly rising temperatures are having great effects on the high arctic ecosystem, historically characterized by long, cold winter periods, and cold dry summers. Due to the length of the winter season, arctic soils have been an important carbon sink, but may now be facing increased microbial activity due to increasing temperatures. Temperature, moisture, and litter quality play important roles in decomposition processes, where winter temperature, summer moisture, and plant community composition is strongly influenced by the amount of accumulated snow during the winter period. Increased winter snow depth has been found to increase winter soil temperatures, therefore increasing microbial activity and decomposition in the winter period. Decomposition of green and rooibos tea bags was studied in a long-term experiment in Adventdalen, Svalbard, where snow was manipulated behind snow fences to create Ambient, Medium, and Deep regimes. Open top chambers (OTCs) were used to measure simulated warmer summer temperatures on tea bag decomposition. Decomposition was measured for an annual term (September 2017-August 2018), a winter term (September 2017-June 2018), and a summer term (June 2018-August 2018, inside and outside of open top chambers). Temperature loggers recorded soil surface temperature hourly throughout the study period. Enhanced snow depth increased winter temperatures in the Deep and Medium snow regimes compared to Ambient. The Deep regime had delayed snowmelt compared to the Ambient and Medium regimes, and was coolest regime during the summertime. The Medium regime was the warmest regime during summer, by visual observation. Soil moisture decreased in all snow regimes over the course of the summer period, and soil moisture measured inside of OTCs was lower than outside of OTCs. Green tea and rooibos tea demonstrated different patterns of decomposition under the varying snow depth regimes. Annual decomposition was lowest in the Deep regime for both substrates. Annual decomposition was highest in Medium for green tea and highest in Ambient for rooibos tea. Decomposition was lower inside of OTCs than outside of OTCs for both types of tea. These results demonstrate the complexity of the processes driving decomposition in Arctic soils. Increased snow cover may cause lower decomposition in long-term studies where plant and microbial community composition may have changed over time, suggesting that winter soil temperatures alone may not be as important in these changing ecosystems

MOLT PATTERNS AND SEXING AND AGING CRITERIA FOR TEN SPECIES OF HIGH ELEVATION LANDBIRDS FROM SOUTHEASTERN PERU

Abstract ∙ Knowledge of molt patterns and their resulting plumages is useful for aging and sexing birds and, in mono‐ chromatic species, morphometric measurements can help to discern males from females. However, these data are largely undescribed for the majority of the world’s bird species, especially in the tropics. We sought to classify the molt strategy for 10 species of Neotropical passerines during their breeding seasons and considered whether a combination of wing chord, tail length and mass could be used to determine their sex. We used banding data from three years of mark‐recapture study at Wayqecha Biological Station (2900 m a.s.l.) along the east slope of the Andes in southeastern Peru to characterize molt and estimate morphological measurements. Each of the species exhibited a complete definitive prebasic molt and either a partial (nine species) or partial‐incomplete (one species) preformative molt, which we interpreted to be consistent with a complex basic molt strategy. For five of the 10 species, we found that wing, tail, and body mass measurements were useful in distinguishing between males and females. This study contributes to our understanding of tropical bird molt by providing previously undescribed aging and sexing criteria for some tropical landbirds common to high elevations of southern Peru.Resumen ∙ Patrones de muda y criterios para categorizar sexo y edad en diez especies de aves altoandinas en el sureste de Perú Los patrones de muda en la mayoría de las aves Neotropicales son poco conocidos y en especial se desconoce si las medidas corporales pueden ser usadas para determinar el sexo en especies sin dimorfismo sexual. En este trabajo clasificamos la estrategia de muda para 10 especies de paserinos Neotropicales y también exploramos si una combi‐ nación de medidas de longitud del ala, longitud de la cola y masa corporal pueden ser usadas para la determinación del sexo. Usamos datos de anillamiento de tres años de un estudio de recaptura en la Estación Biológica Wayqecha (2900 m s.n.m.) en el flanco oriental de los Andes al sureste de Perú. Cada especie exhibió una estrategia básica compleja de muda con una muda prebásica definitiva compleja, y una muda preformativa parcial (nueve especies) o parcial‐incompleta (uno especie). Para cinco de cada 10 especies, la combinación de medidas de la longitud del ala, la cola, y la masa corporal sirvieron para distinguir entre machos y hembras. Este estudio contribuye a la creciente literatura sobre los patrones de muda en aves tropicales y provee herramientas para clasificar la edad y el sexo de aves con plumaje sexualmente monocromático

General anaesthetic and airway management practice for obstetric surgery in England: a prospective, multi-centre observational study

There are no current descriptions of general anaesthesia characteristics for obstetric surgery, despite recent changes to patient baseline characteristics and airway management guidelines. This analysis of data from the direct reporting of awareness in maternity patients' (DREAMY) study of accidental awareness during obstetric anaesthesia aimed to describe practice for obstetric general anaesthesia in England and compare with earlier surveys and best-practice recommendations. Consenting patients who received general anaesthesia for obstetric surgery in 72 hospitals from May 2017 to August 2018 were included. Baseline characteristics, airway management, anaesthetic techniques and major complications were collected. Descriptive analysis, binary logistic regression modelling and comparisons with earlier data were conducted. Data were collected from 3117 procedures, including 2554 (81.9%) caesarean deliveries. Thiopental was the induction drug in 1649 (52.9%) patients, compared with propofol in 1419 (45.5%). Suxamethonium was the neuromuscular blocking drug for tracheal intubation in 2631 (86.1%), compared with rocuronium in 367 (11.8%). Difficult tracheal intubation was reported in 1 in 19 (95%CI 1 in 16-22) and failed intubation in 1 in 312 (95%CI 1 in 169-667). Obese patients were over-represented compared with national baselines and associated with difficult, but not failed intubation. There was more evidence of change in practice for induction drugs (increased use of propofol) than neuromuscular blocking drugs (suxamethonium remains the most popular). There was evidence of improvement in practice, with increased monitoring and reversal of neuromuscular blockade (although this remains suboptimal). Despite a high risk of difficult intubation in this population, videolaryngoscopy was rarely used (1.9%)

Distribution, habitat use, and migratory life history of Southern Dolly Varden (Salvelinus malma lordi) in a salmon-bearing watershed on the Central Coast, British Columbia

Anadromous freshwater fishes are among the most threatened vertebrates in North America. Population declines and collapses due to overfishing, habitat loss, and climate change have long been documented for socioeconomically important salmonids such as Pacific salmon (Oncorhynchus spp), but the conservation status of other species such as Dolly Varden char (Salvelinus malma) remains largely unknown. Even without the pressures of direct commercial harvest, many anadromous salmonids may still be vulnerable to the other threats faced by commercially-harvested species, but conservation efforts continue to be hampered by a lack of basic life history and demographic information. While the Northern Dolly Varden (S. m. malma) has been assessed as “Special Concern” by the Committee on the Status of Endangered Wildlife in Canada, the Southern Dolly Varden (S. m. lordi) has received little conservation attention despite near ubiquity in coastal watersheds from Alaska to Washington, partly due to a lack of data throughout the broad coastal range. I conducted surveys on a population of Southern Dolly Varden in a lake-headed coastal watershed on the mid coast of British Columbia to identify key spawning, rearing, and foraging habitat, to characterize seasonal patterns in their iteroparous anadromous migratory life history, and to assess the extent of migratory coupling among Pacific salmon and Dolly Varden throughout the year. I found that Dolly Varden used a wide range of habitats distributed throughout the entire watershed, and that there were distinct seasonal movements that were temporally associated with Pacific salmon migrations. My observations indicate that this population of Southern Dolly Varden requires the entire extent of the watershed, from lake tributaries to the estuarine river mouth, for individuals to express their complete migratory life history, and that this population is vulnerable to any disturbance leading to the degradation or loss of access to key habitats for spawning, rearing, and foraging. This population could serve as a baseline for understanding the conservation status of Southern Dolly Varden throughout the rest of the range, and can be used as a rare model for studying predator-prey migratory coupling as it relates to socioeconomically important species of Pacific salmon.Science, Faculty ofZoology, Department ofGraduat

Decomposition in differing snow regimes in high Arctic Svalbard

Rapidly rising temperatures are having great effects on the high arctic ecosystem, historically characterized by long, cold winter periods, and cold dry summers. Due to the length of the winter season, arctic soils have been an important carbon sink, but may now be facing increased microbial activity due to increasing temperatures. Temperature, moisture, and litter quality play important roles in decomposition processes, where winter temperature, summer moisture, and plant community composition is strongly influenced by the amount of accumulated snow during the winter period. Increased winter snow depth has been found to increase winter soil temperatures, therefore increasing microbial activity and decomposition in the winter period. Decomposition of green and rooibos tea bags was studied in a long-term experiment in Adventdalen, Svalbard, where snow was manipulated behind snow fences to create Ambient, Medium, and Deep regimes. Open top chambers (OTCs) were used to measure simulated warmer summer temperatures on tea bag decomposition. Decomposition was measured for an annual term (September 2017-August 2018), a winter term (September 2017-June 2018), and a summer term (June 2018-August 2018, inside and outside of open top chambers). Temperature loggers recorded soil surface temperature hourly throughout the study period. Enhanced snow depth increased winter temperatures in the Deep and Medium snow regimes compared to Ambient. The Deep regime had delayed snowmelt compared to the Ambient and Medium regimes, and was coolest regime during the summertime. The Medium regime was the warmest regime during summer, by visual observation. Soil moisture decreased in all snow regimes over the course of the summer period, and soil moisture measured inside of OTCs was lower than outside of OTCs. Green tea and rooibos tea demonstrated different patterns of decomposition under the varying snow depth regimes. Annual decomposition was lowest in the Deep regime for both substrates. Annual decomposition was highest in Medium for green tea and highest in Ambient for rooibos tea. Decomposition was lower inside of OTCs than outside of OTCs for both types of tea. These results demonstrate the complexity of the processes driving decomposition in Arctic soils. Increased snow cover may cause lower decomposition in long-term studies where plant and microbial community composition may have changed over time, suggesting that winter soil temperatures alone may not be as important in these changing ecosystems

Data from: Linking the wintering and breeding grounds of warblers along the Pacific Flyway

Long-distance migration is a behavior that is exhibited by many animal groups. The evolution of novel migration routes can play an important role in range expansions, ecological interactions, and speciation. New migration routes may evolve in response to selection in favor of reducing distance between breeding and wintering areas, or avoiding navigational barriers. Many migratory changes are likely to evolve gradually and are therefore difficult to study. Here, we attempt to connect breeding and wintering populations of myrtle warblers (Setophaga coronata coronata) to better understand the possible evolution of distinct migration routes within this species. Myrtle warblers, unlike most other warblers with breeding ranges primarily in eastern North America, have two disjunct overwintering concentrations—one in the southeastern USA and one along the Pacific Coast—and presumably distinct routes to-and-from these locations. We studied both myrtle and Audubon's warblers (S. c. auduboni) captured during their spring migration along the Pacific Coast, south of the narrow region where these two taxa hybridize. Using stable hydrogen isotopes and biometric data, we show that those myrtle warblers wintering along the southern Pacific Coast of North America are likely to breed at high latitudes in Alaska and the Yukon rather than in Alberta or further east. Our interpretation is that the evolution of this wintering range and migration route along the Pacific Coast may have facilitated the breeding expansion of myrtle warblers into northwestern North America. Moreover, these data suggest that there may be a migratory divide within genetically similar populations of myrtle warblers

MOLT PATTERNS AND SEXING AND AGING CRITERIA FOR TEN SPECIES OF HIGH ELEVATION LANDBIRDS FROM SOUTHEASTERN PERU

Abstract ∙ Knowledge of molt patterns and their resulting plumages is useful for aging and sexing birds and, in mono‐ chromatic species, morphometric measurements can help to discern males from females. However, these data are largely undescribed for the majority of the world’s bird species, especially in the tropics. We sought to classify the molt strategy for 10 species of Neotropical passerines during their breeding seasons and considered whether a combination of wing chord, tail length and mass could be used to determine their sex. We used banding data from three years of mark‐recapture study at Wayqecha Biological Station (2900 m a.s.l.) along the east slope of the Andes in southeastern Peru to characterize molt and estimate morphological measurements. Each of the species exhibited a complete definitive prebasic molt and either a partial (nine species) or partial‐incomplete (one species) preformative molt, which we interpreted to be consistent with a complex basic molt strategy. For five of the 10 species, we found that wing, tail, and body mass measurements were useful in distinguishing between males and females. This study contributes to our understanding of tropical bird molt by providing previously undescribed aging and sexing criteria for some tropical landbirds common to high elevations of southern Peru.Resumen ∙ Patrones de muda y criterios para categorizar sexo y edad en diez especies de aves altoandinas en el sureste de Perú Los patrones de muda en la mayoría de las aves Neotropicales son poco conocidos y en especial se desconoce si las medidas corporales pueden ser usadas para determinar el sexo en especies sin dimorfismo sexual. En este trabajo clasificamos la estrategia de muda para 10 especies de paserinos Neotropicales y también exploramos si una combi‐ nación de medidas de longitud del ala, longitud de la cola y masa corporal pueden ser usadas para la determinación del sexo. Usamos datos de anillamiento de tres años de un estudio de recaptura en la Estación Biológica Wayqecha (2900 m s.n.m.) en el flanco oriental de los Andes al sureste de Perú. Cada especie exhibió una estrategia básica compleja de muda con una muda prebásica definitiva compleja, y una muda preformativa parcial (nueve especies) o parcial‐incompleta (uno especie). Para cinco de cada 10 especies, la combinación de medidas de la longitud del ala, la cola, y la masa corporal sirvieron para distinguir entre machos y hembras. Este estudio contribuye a la creciente literatura sobre los patrones de muda en aves tropicales y provee herramientas para clasificar la edad y el sexo de aves con plumaje sexualmente monocromático.</jats:p

Raw hydrogen isotope values and bird measurements

Raw hydrogen isotope values and bird measurement

Isomap Assignment Output Files

IsoMAP output files in .asc format for each feather. Directory substructure represents species (Audubon's versus myrtle) and is further divided by molt, with "alt" (alternate feather) versus basic (basic feather)