Short and long-term outcomes of surgery for inflammatory (uncomplicated) ileocecal Crohn's disease: Multicentric retrospective analysis of 211 patients.

BACKGROUND: Surgical management for patients with inflammatory ileocecal Crohn's disease (CD) could be a reasonable alternative to second-line medical treatment. AIM: To assess short and long-term outcomes of patients operated on for inflammatory, ileocecal Crohn's disease. METHODS: A retrospective analysis of patients intervened at four referral hospitals during 2012-2021 was performed. RESULTS: 211 patients were included. 43% of patients underwent surgery more than 5 years after diagnosis, and 49% had been exposed to at least one biologic agent preoperatively. 89% were operated by laparoscopy, with 1.6% conversion rate. The median length of the resected bowel was 25 cm (7-92) and three patients (1.43%) received a stoma. Median follow-up was 36 (17-70) months. The endoscopic recurrence-free survival proportion at 24, 48, 72, 96, and 120 months was 56%, 52%, 45%, 38%, and 33%, respectively. The clinical recurrence-free survival proportion at 24, 48, 72, 96, and 120 months was 83%, 79%, 76%, 74%, and 74%, respectively. In multivariate analysis, previous biological treatment (HR=2.01; p = 0.001) was associated with a higher risk of overall recurrence. CONCLUSION: Surgery in patients with primary inflammatory ileocecal CD is associated with good postoperative outcomes, low postoperative morbidity with reasonable recurrence rates.

Short-term outcomes following total colectomy for inflammatory bowel disease in Denmark after implementation of laparoscopy: a nationwide population-based study.

AIM: A laparoscopic approach to total colectomy (TC) for inflammatory bowel disease (IBD) is being increasingly used, but data on its comparative benefits over open TC are conflicting. The aim of this study was to examine 90-day outcomes following laparoscopic and open TC for IBD in a nationwide cohort after the introduction of laparoscopy. METHOD: IBD patients undergoing TC in Denmark from 2005 to 2017 were identified from the Danish National Patient Registry. We used Kaplan-Meier methodology to estimate mortality and Cox regression analysis to estimate adjusted mortality rate ratios (aMRRs) and adjusted hazard ratios (aHRs) of reoperation, readmission and intensive care unit (ICU) transfer, comparing patients undergoing laparoscopic versus open TC. RESULTS: We identified 1095 patients undergoing laparoscopic TC and 1523 patients undergoing open TC. Following emergency TC, 90-day mortality was 2.8% (1.6%-4.9%) after laparoscopic TC and 9.1% (7.0%-11.8%) after open TC. Ninety-day mortality was 0.9% (0.3%-2.5%) after laparoscopic TC and 2.6% (1.5%-4.3%) after open elective TC. The aMRRs associated with laparoscopic TC were 0.45 (95% CI 0.25-0.80) in emergency cases and 0.29 (95% CI 0.10-0.86) in elective cases. Risks of readmission were comparable following laparoscopic versus open TC, both in emergency [aHR = 0.93 (95% CI 0.76-1.15)] and elective [aHR = 0.83 (95% CI 0.68-1.02)] cases, while risks of ICU transfer and reoperation were lower following laparoscopic TC, both in emergency cases [aHR = 0.53 (95% CI 0.35-0.82) and aHR = 0.26 (95% CI 0.15-0.47)] and elective [aHR = 0.58 (95% CI 0.35-0.95) and aHR = 0.37 (95% CI 0.21-0.66)] cases. CONCLUSION: The introduction of laparoscopic TC for IBD in Denmark was not associated with increased mortality or morbidity. In fact, laparoscopic TC for IBD may be associated with lower short-term mortality and morbidity compared with open TC.

Short-Term Results of Operative Treatment of Primary Ileocecal Crohn's Disease: Retrospective, Comparative Analysis between Early (Luminal) and Complicated Disease.

Early surgical treatment for patients with ileocecal Crohn's disease (CD) could be an alternative to biological therapy. The aim of this study is to compare operative outcomes following ileocecal resection for patients with luminal and complicated CD. Patients operated for primary ileocecal CD during 8 years in one tertiary-referral hospital were allocated into 2 groups: those operated for early (luminal) disease (ECD), and for complications of CD (CCD). A retrospective comparative analysis was performed. A total of 273 patients were included in the analysis, 85 (31%) of which were in the ECD group. No difference was found regarding time from diagnosis to surgery. Surgical procedures were longer in the CCD group, with lower rates of laparoscopic approach (93 vs. 99%, p = 0.035) and higher conversion rates (20 vs. 2%, p < 0.001). ECD had non-significant differences in terms of major postoperative complications (9.4 vs. 14.9%, p = 0.215), shorter hospital stays, and lower rates of anastomotic leakage (3.5 vs. 6.8%, p = 0.285). Conversely, the CCD group had higher reoperation and re-hospitalization rates. Adequate timing for the indication of surgery in primary ileocecal CD, including an early discussion considering both medical and surgical treatment as options, could positively influence operative outcomes.

Risk of incisional hernia repair in patients with inflammatory bowel disease.

AIM: Patients with inflammatory bowel disease (IBD) may undergo several abdominal surgeries with a risk of incisional hernia repair (IHR). The objectives of this study were to establish the risk of IHR and to analyse predictors of IHR after a first-time abdominal surgery for IBD. METHOD: This Danish nationwide register-based cohort study (1996-2018) followed IBD patients from index operation until the date of IHR. The absolute risk was calculated as the cumulative incidence proportion treating death as a competing risk. Cox proportional hazard regression was used to compare the risk of IHR among different subtypes of IBD and to explore predictors of IHR. IBD subtypes were classified as ulcerative colitis (UC), Crohn's disease (CD) or unclassified IBD (IBD-U). RESULTS: In total, 10 130 patients with IBD (UC 3911 [39%]; CD 4210 [41%]; IBD-U 2009 [20%]) underwent either an open or a laparoscopic index operation. The 10-year cumulative incidence of IHR varied between 5.0% and 6.3%, with a significantly higher risk in patients with UC and IBD-U. Patients with UC (75.9%) and IBD-U (91.9%) had more (two or more) abdominal surgeries in the follow-up period compared with CD (51.9%). The risk of IHR increased dramatically with the number of surgeries, although not as markedly if a laparoscopic approach was used. Male sex, age, comorbidity, fascial dehiscence, wound infection and presence of stoma were predictors of IHR for patients with IBD. CONCLUSION: The long-term risk of IHR was roughly 5%-6%, with a higher risk in patients with UC and IBD-U. Open surgical approach and number of previous surgeries were, among other things, important predictors of IHR.

Activity patterns throughout the annual cycle in a long-distance migratory songbird, the red-backed shrike Lanius collurio.

BACKGROUND: Long-distance migratory birds undergo complex annual cycles during which they must adjust their behaviour according to the needs and conditions encountered throughout the year. Yet, variation in activity throughout the entire annual cycle has rarely been studied in wild migratory birds. METHODS: We used multisensor data loggers to evaluate the patterns of activity throughout the complete annual cycle of a long-distance migratory bird, the red-backed shrike Lanius collurio. Accelerometer data was used to identify life-history stages and to estimate levels of activity during various phases of the annual cycle. In this study, we analysed the variation in daytime activity along the annual cycle and between migratory and non-migratory days. RESULTS: The birds' daytime activity varied throughout the annual cycle while night-time activity was almost exclusively restricted to migratory flights. The highest daytime activity levels were observed during the breeding season, while it remained low during autumn migration and the winter period. Daytime activity differed between sexes during the breeding period, when the males showed the highest level in activity. During migratory periods, both sexes exhibited a higher daytime activity in spring compared to autumn migration, being particularly high in the final migratory leg towards the breeding ground. The birds showed a lower daytime activity on migratory days (days when a migratory flight took place during the succeeding night) than on non-migratory days during both migratory seasons. CONCLUSIONS: Activity measured during daytime results from a combination of several behaviours, and a high daytime activity during spring migration and the breeding period is possibly reflecting particularly energy-demanding periods in the annual cycle of migratory birds. The use of multisensor data loggers to track annual activity provides us with a full annual perspective on variation in activity in long-distance migratory species, an essential approach for understanding possible critical life-history stages and migration ecology.

Implementation of a standardized surgical technique in robot-assisted restorative rectal cancer resection: a single center cohort study.

BACKGROUND: Despite increasing focus on the technical performance of total mesorectal excision over recent decades, anastomotic leakage (AL) continues to be a serious complication for many patients, even in the hands of experienced surgical teams. This study describes implementation of standardized surgical technique in an effort to reduce variability, decrease the risk of anastomotic leakage, and improve associated short-term outcomes for rectal cancer patients undergoing robot-assisted restorative rectal resection (RRR). METHODS: We evaluated all rectal cancer patients undergoing robot-assisted RRR at Aarhus University Hospital between 2017 and 2020. Six standardized surgical steps directed to improve anastomotic healing were mandatory for all RRR. Additional changes were made during the period with prohibition of systemic dexamethasone and limiting the use of endoscopic stapling devices. RESULTS: The use of the full standardization, including all six surgical steps, increased from 40.3% (95% CI, 0.28-0.54) to 86.2% (95% CI, 0.68-0.95). The incidence of AL decreased from 21.0% (95% CI, 0.12-0.33) to 6.9% (95% CI, 0.01-0.23). Length of hospital stay (LOS) decreased from 6 days (range 2-50) to 5 days (range 2-26). The rate of patients readmitted within 90 days decreased from 21.0% (95% CI, 0.12-0.33), to 6.9% (95% CI, 0.01-0.23). CONCLUSION: The full standardization was effectively implemented for rectal cancer patients undergoing robot-assisted RRR. The risk of AL, LOS and readmission decreased during the study period. A team focus on high-reliability and peri-operative complications can improve patient outcomes.

Biomechanical Properties of Strictures in Crohn's Disease: Can Dynamic Contrast-Enhanced Ultrasonography and Magnetic Resonance Enterography Predict Stiffness?

Strictures and abdominal pain often complicate Crohn's disease (CD). The primary aim was to explore whether parameters obtained by preoperative contrast-enhanced (CE) ultrasonography (US) and dynamic CE MR Enterography (DCE-MRE) of strictures associates with biomechanical properties. CD patients undergoing elective small intestinal surgery were preoperatively examined with DCE-MRE and CEUS. The excised intestine was distended utilizing a pressure bag. Luminal and outer bowel wall cross-sectional areas were measured with US. The circumferential stricture stiffness (Young's modulus E) was computed. Stiffness was associated with the initial slope of enhancement on DCE-MRE (ρ = 0.63, p = 0.007), reflecting active disease, but lacked association with CEUS parameters. For structural imaging parameters, inflammation and stricture stiffness were associated with prestenotic dilatation on US (τb = 0.43, p = 0.02) but not with MRE (τb = 0.01, p = 1.0). Strictures identified by US were stiffer, 16.8 (14.0-20.1) kPa, than those graded as no or uncertain strictures, 12.6 (10.5-15.1) kPa, p = 0.02. MRE global score (activity) was associated with E (ρ = 0.55, p = 0.018). Elastography did not correlate with circumferential stiffness. We conclude that increasing activity defined by the initial slope of enhancement on DCE-MRE and MRE global score were associated with stricture stiffness. Prestenotic dilatation on US could be a potential biomarker of CD small intestinal stricture stiffness.

Functional outcome and quality of life after transanal minimal invasive pouch surgery.

PURPOSE: To investigate functional outcomes and quality of life (QoL) after restorative proctocolectomy (RPC) using transanal minimal invasive surgery (TAMIS). METHOD: The study consists of two sub-studies. A cohort study comprised 98 consecutive patients, who underwent TAMIS RPC. These patients were the first at our department to undergo TAMIS RPC. We collected information about surgery, complications, postoperative morbidity and mortality ≤ 30 days, and pouch problems. Patients were also invited to participate in a case-control study in which the patients would respond to three different questionnaires, the Inflammatory Bowel Disease Questionnaire (IBDQ), the Short Form-36 General Health Questionnaire (SF-36), and questions from the Pouch Dysfunction Score. We compared the responding TAMIS RPC patients to a Danish national cohort (0-10 years from RPC, n = 514) of patients having RPC between 1980 and 2010. We compared functional outcomes and QoL. RESULTS: Four (4%) of the TAMIS patients had an anastomotic leak; none of these required re-operation with removal of the pouch. Anastomotic leak was treated with antibiotics and drain. Out of the four leaks, only one ended up with a permanent stoma; all others had their stoma reversed successfully. The TAMIS patients had the same number of bowel movements as the patients in the Danish national cohort study. The same was seen with regard to incontinence. We had no conversions in our series of TAMIS procedures. CONCLUSION: The TAMIS technique shows acceptable outcomes, both in regard to postoperative complications and also functional outcome and QoL.

A comparison of herbarium and citizen science phenology datasets for detecting response of flowering time to climate change in Denmark.

Phenology has emerged as a key metric to measure how species respond to changes in climate. Innovative means have been developed to extend the temporal and spatial range of phenological data by obtaining data from herbarium specimens, citizen science programs, and biodiversity data repositories. These different data types have seldom been compared for their effectiveness in detecting environmental impacts on phenology. To address this, we compare three separate phenology datasets from Denmark: (i) herbarium specimen data spanning 145 years, (ii) data collected from a citizen science phenology program over a single year observing first flowering, and (iii) data derived from incidental biodiversity observations in iNaturalist over a single year. Each dataset includes flowering day of year observed for three common spring-flowering plant species: Allium ursinum (ramsons), Aesculus hippocastanum (horse chestnut), and Sambucus nigra (black elderberry). The incidental iNaturalist dataset provided the most extensive geographic coverage across Denmark and the largest sample size and recorded peak flowering in a way comparable to herbarium specimens. The directed citizen science dataset recorded much earlier flowering dates because the program objective was to report the first flowering, and so was less compared to the other two datasets. Herbarium data demonstrated the strongest effect of spring temperature on flowering in Denmark, possibly because it was the only dataset measuring temporal variation in phenology, while the other datasets measured spatial variation. Herbarium data predicted the mean flowering day of year recorded in our iNaturalist dataset for all three species. Combining herbarium data with iNaturalist data provides an even more effective method for detecting climatic effects on phenology. Phenology observations from directed and incidental citizen science initiatives will increase in value for climate change research in the coming years with the addition of data capturing the inter-annual variation in phenology.

Patient-Reported Outcomes and Health-Related Quality of Life in People Living With Ileostomies: A Population-Based, Cross-Sectional Study.

BACKGROUND: The impact of a stoma on long-term health-related quality of life in people living with ileostomies is not clear. OBJECTIVE: This study aimed to describe important patient-reported outcomes and health-related quality of life in people with ileostomies. DESIGN: This is a population-based, cross-sectional study. Patients were invited to answer questionnaires estimating stoma-specific and generic health-related quality of life (EQ-5D-5L and the Major Depression Inventory). Danish norms were retrieved from reference literature. SETTINGS: This study was conducted at the major stoma clinic at Aarhus University Hospital, Denmark. PATIENTS: We invited all patients with ileostomies who were in contact with the clinic between 2012 and 2017. MAIN OUTCOME MEASURES: The primary outcomes measured were patient-reported outcomes specific to people with ileostomies. RESULTS: Of 621 identified patients (50% women), 412 (67%) responded to the survey. Among the responders, 178 (43%) reported that they still had an ileostomy at the time of the survey and were included in the analysis. Fatigue was frequent; 68% (95% CI 60%-75%) reported being tired and 26% (95% CI 20%-33%) answered that they were "always tired," whereas 43% (95% CI 36%-51%) lacked energy, 62% (95% CI 54%-69%) reported poor sleep, and 59% (95% CI 52%-66%) needed to rest during the day. Fifty-six percent (95% CI 48%-63%) needed to know the immediate location of the nearest toilet, and 58% (95% CI 51%-66%) felt sexually unattractive because of their ileostomy. Health-related quality of life measured with generic questions indicated 0.124 points lower health-related quality of life than the Danish norm ( p < 0.001), and 18% (95% CI 13%-25%) scored above the threshold for depression, which is 2.6 times higher than the background population (7%, 95% CI 6%-9%; p < 0.001). LIMITATIONS: This study was limited by potential selection bias, and all participants did not answer all items. CONCLUSIONS: Fatigue and low health-related quality of life is common in people living with ileostomies. Addressing fatigue and stoma-specific challenges in patients with an ileostomy is warranted. See Video Abstract at http://links.lww.com/DCR/B803 . DESENLACES INFORMADOS POR PACIENTES Y CALIDAD DE VIDA RELACIONADA CON LA SALUD EN PERSONAS QUE VIVEN CON ILEOSTOMAS UN ESTUDIO TRANSVERSAL POBLACIONAL: ANTECEDENTES:El impacto de un estoma en la calidad de vida relacionada con la salud a largo plazo en personas que viven con ileostomías no está claro.OBJETIVO:Describir desenlaces importantes informados por pacientes y la calidad de vida relacionada con la salud en personas con ileostomías.DISEÑO:Estudio transversal poblacional. Se invitó a los pacientes a responder cuestionarios que estiman la calidad de vida relacionada con la salud general y específica del estoma (EQ-5D-5L y el Inventario de depresión mayor). Las normas danesas se recopilaron de la literatura de referencia.AJUSTES:El estudio se llevó a cabo en la clínica principal de estomas del Hospital Universitario de Aarhus, Dinamarca.PACIENTES:Invitamos a todos los pacientes con ileostomías que estuvieron en contacto con la clínica entre 2012 y 2017.PRINCIPALES MEDIDAS DE RESULTADO:Resultados informados por el paciente específicos para personas con ileostomías.RESULTADOS:De 621 pacientes identificados (50% mujeres), 412 (66%) respondieron la encuesta. Entre los que respondieron, 178 (43%) informaron que todavía tenían una ileostomía en el momento de la encuesta y fueron incluidos en el análisis. La fatiga era frecuente; el 68% (intervalo de confianza del 95%: 60-75%) informó estar cansado y el 26% (20-33%) respondió "siempre cansado", mientras que el 43% (36-51%) carecía de energía, el 62% (54-69%)) refirieron dormir mal y el 59% (52-6%) necesitaba descansar durante el día. El cincuenta y seis por ciento (48-63%) necesitaba saber la ubicación inmediata del baño más cercano y el 58% (51-66%) se sentía sexualmente poco atractivo debido a su ileostomía. La calidad de vida relacionada con la salud medida con preguntas genéricas indicó una calidad de vida relacionada con la salud 0,124 puntos más baja que la norma danesa ( p < 0,001), y el 18% (13-25%) puntuó con depresión, que es 2.6 veces más alta que la población de base (7%, 6-9%, p < 0,001).LIMITACIONES:Posible sesgo de selección, y no todos los participantes respondieron a todos los ítems.CONCLUSIONES:La fatiga y la baja calidad de vida relacionada con la salud es común en las personas que viven con ileostomías. Se justifica abordar la fatiga y los desafíos específicos del estoma en pacientes con una ileostomía. Consulte Video Resumen en http://links.lww.com/DCR/B803 . (Traducción-Juan Carlos Reyes ).

Danish Society for Gastroenterology and Hepatology's clinical recommendations for colonoscopic surveillance for colorectal dysplasia and cancer in patients with inflammatory bowel disease.

OBJECTIVES: We aimed to produce clinical recommendations for colonoscopic surveillance for dysplasia and colorectal cancer in patients with inflammatory bowel diseases. MATERIALS AND METHODS: The Danish Society for Gastroenterology and Hepatology convened a committee to assess the literature on colorectal cancer in inflammatory bowel diseases and the effectiveness of colonoscopy surveillance, according to the Oxford Centre for Evidence Based Medicine levels of evidence. RESULTS: Clinical recommendations for the colonoscopic surveillance for dysplasia and colorectal cancer in patients with inflammatory bowel diseases were produced. These guidelines cover the risk stratification, entry, and follow-up of patients in the colonoscopy programme, the choice of image-enhanced colonoscopy modality, the investigation and treatment of lesions, and the management of special patient populations in the colonoscopy programme. CONCLUSIONS: Colonoscopic surveillance of inflammatory bowel disease is thought to be associated with a decreased risk of colorectal cancer and colorectal cancer-related mortality. Further evidence regarding the effectiveness of colonoscopic surveillance will contribute to understanding its role in the management of inflammatory bowel diseases. The Danish Society for Gastroenterology and Hepatology clinical guideline will aid gastroenterologists in the risk stratification of patients with inflammatory bowel disease, and the management of colorectal lesions. Gastroenterologists must inform and support patients with inflammatory bowel disease to decide whether to participate in the colonoscopic surveillance programme.

Response of an Afro-Palearctic bird migrant to glaciation cycles.

Migration allows animals to exploit spatially separated and seasonally available resources at a continental to global scale. However, responding to global climatic changes might prove challenging, especially for long-distance intercontinental migrants. During glacial periods, when conditions became too harsh for breeding in the north, avian migrants have been hypothesized to retract their distribution to reside within small refugial areas. Here, we present data showing that an Afro-Palearctic migrant continued seasonal migration, largely within Africa, during previous glacial-interglacial cycles with no obvious impact on population size. Using individual migratory track data to hindcast monthly bioclimatic habitat availability maps through the last 120,000 y, we show altered seasonal use of suitable areas through time. Independently derived effective population sizes indicate a growing population through the last 40,000 y. We conclude that the migratory lifestyle enabled adaptation to shifting climate conditions. This indicates that populations of resource-tracking, long-distance migratory species could expand successfully during warming periods in the past, which could also be the case under future climate scenarios.

Detecting flying insects using car nets and DNA metabarcoding.

Monitoring insects across space and time is challenging, due to their vast taxonomic and functional diversity. This study demonstrates how nets mounted on rooftops of cars (car nets) and DNA metabarcoding can be applied to sample flying insect richness and diversity across large spatial scales within a limited time period. During June 2018, 365 car net samples were collected by 151 volunteers during two daily time intervals on 218 routes in Denmark. Insect bulk samples were processed with a DNA metabarcoding protocol to estimate taxonomic composition, and the results were compared to known flying insect richness and occurrence data. Insect and hoverfly richness and diversity were assessed across biogeographic regions and dominant land cover types. We detected 15 out of 19 flying insect orders present in Denmark, with high proportions of especially Diptera compared to Danish estimates, and lower insect richness and diversity in urbanized areas. We detected 319 species not known for Denmark and 174 species assessed in the Danish Red List. Our results indicate that the methodology can assess the flying insect fauna at large spatial scales to a wide extent, but may be, like other methods, biased towards certain insect orders.

Temporal trends of legacy organochlorines in different white-tailed eagle (Haliaeetus albicilla) subpopulations: A retrospective investigation using archived feathers.

Understanding the spatiotemporal patterns of legacy organochlorines (OCs) is often difficult because monitoring practices differ among studies, fragmented study periods, and unaccounted confounding by ecological variables. We therefore reconstructed long-term (1939-2015) and large-scale (West Greenland, Norway, and central Sweden) trends of major legacy OCs using white-tailed eagle (Haliaeetus albicilla) body feathers, to understand the exposure dynamics in regions with different contamination sources and concentrations, as well as the effectiveness of legislations. We included dietary proxies (δ13C and δ15N) in temporal trend models to control for potential dietary plasticity. Consistent with the hypothesised high local pollution sources, levels of polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethanes (DDTs) and hexachlorocyclohexanes (HCHs) in the Swedish subpopulation exceeded those in the other subpopulations. In contrast, chlordanes (CHLs) and hexachlorobenzene (HCB) showed higher concentrations in Greenland, suggesting the importance of long-range transport. The models showed significantly decreasing trends for all OCs in Sweden in 1968-2011 except for CHLs, which only decreased since the 1980s. Nevertheless, median concentrations of DDTs and PCBs remained elevated in the Swedish subpopulation throughout the 1970s, suggesting that the decreases only commenced after the implementation of regulations during the 1970s. We observed significant trends of increasing concentrations of PCBs, CHLs and HCB in Norway from the 1930s to the 1970s/1980s and decreasing concentrations thereafter. All OC concentrations, except those of PCBs were generally significantly decreasing in the Greenland subpopulation in 1985-2013. All three subpopulations showed generally increasing proportions of the more persistent compounds (CB 153, p.p'-DDE and ß-HCH) and decreasing proportions of the less persistent ones (CB 52, p.p'-DDT, α- and γ-HCH). Declining trends of OC concentrations may imply the decreasing influence of legacy OCs in these subpopulations. Finally, our results demonstrate the usefulness of archived museum feathers in retrospective monitoring of spatiotemporal trends of legacy OCs using birds of prey as sentinels.

Desert crossing strategies of migrant songbirds vary between and within species.

Each year, billions of songbirds cross large ecological barriers during their migration. Understanding how they perform this incredible task is crucial to predict how global change may threaten the safety of such journeys. Earlier studies based on radar suggested that most songbirds cross deserts in intermittent flights at high altitude, stopping in the desert during the day, while recent tracking with light loggers suggested diurnal prolongation of nocturnal flights and common non-stop flights for some species. We analyzed light intensity and temperature data obtained from geolocation loggers deployed on 130 individuals of ten migratory songbird species, and show that a large variety of strategies for crossing deserts exists between, but also sometimes within species. Diurnal stopover in the desert is a common strategy in autumn, while most species prolonged some nocturnal flights into the day. Non-stop flights over the desert occurred more frequently in spring than in autumn, and more frequently in foliage gleaners. Temperature recordings suggest that songbirds crossed deserts with flight bouts performed at various altitudes according to species and season, along a gradient ranging from low above ground in autumn to probably >2000 m above ground level, and possibly at higher altitude in spring. High-altitude flights are therefore not the general rule for crossing deserts in migrant songbirds. We conclude that a diversity of migration strategies exists for desert crossing among songbirds, with variations between but also within species.

White-Tailed Eagle (Haliaeetus albicilla) Body Feathers Document Spatiotemporal Trends of Perfluoroalkyl Substances in the Northern Environment.

We reconstructed the first long-term (1968-2015) spatiotemporal trends of perfluoroalkyl substances (PFAS) using archived body feathers of white-tailed eagles (Haliaeetus albicilla) from the West Greenland (n = 31), Norwegian (n = 66), and Central Swedish Baltic coasts (n = 50). We observed significant temporal trends of perfluorooctane sulfonamide (FOSA), perfluorooctane sulfonate (PFOS), and perfluoroalkyl carboxylates (∑PFCAs) in all three subpopulations. Concentrations of FOSA and PFOS had started decreasing significantly since the mid-1990s to 2000 in the Greenland and Norwegian subpopulations, consistent with the 3M phase-out, though in sharp contrast to overall increasing trends observed in the Swedish subpopulation. Moreover, ∑PFCA concentrations significantly increased in all three subpopulations throughout the study periods. These temporal trends suggest on-going input of PFOS in the Baltic and of ∑PFCAs in all three regions. Considerable spatial variation in PFAS concentrations and profiles was observed: PFOS concentrations were significantly higher in Sweden, whereas FOSA and ∑PFCA concentrations were similar among the subpopulations. PFOS dominated the PFAS profiles in the Swedish and Norwegian subpopulations, in contrast to the domination of FOSA and ∑PFCAs in the Greenland one. Our spatiotemporal observations underline the usefulness of archived bird of prey feathers in monitoring spatiotemporal PFAS trends and urge for continued monitoring efforts in each of the studied subpopulations.

Sex-specific difference in migration schedule as a precursor of protandry in a long-distance migratory bird.

Protandry, the earlier arrival of males at the breeding grounds relative to females, is common in migratory birds. However, due to difficulties in following individual birds on migration, we still lack knowledge about the spatiotemporal origin of protandry during the annual cycle, impeding our understanding of the proximate drivers of this phenomenon. Here, we use full annual cycle tracking data of red-backed shrikes Lanius collurio to investigate the occurrence of sex-related differences in migratory pattern, which could be viewed as precursors (proximate causes) to protandry. We find protandry with males arriving an estimated 8.3 days (SE = 4.1) earlier at the breeding area than females. Furthermore, we find that, averaged across all departure and arrival events throughout the annual cycle, males migrate an estimated 5.3 days earlier than females during spring compared to 0.01 days in autumn. Event-wise estimates suggest that a divergence between male and female migratory schedules is initiated at departure from the main non-breeding area, thousands of kilometres from-, and several months prior to arrival at the breeding area. Duration of migration, flight speed during migration and spatial locations of stationary sites were similar between sexes. Our results reveal that protandry might arise from sex-differential migratory schedules emerging at the departure from the main non-breeding area in southern Africa and retained throughout spring migration, supporting the view that sex-differential selection pressure operates during spring migration rather than autumn migration.