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The Steller’s eider Polysticta stelleri is a sea duck that breeds in Arctic tundra regions of Russia and Alaska (USA). The Alaska-breeding population is listed as ‘threatened’ under the US Endangered Species Act because of a perceived contraction of the breeding range in North America. Understanding demography of the listed population is critical for evaluating measures that can lead to increased abundance and thus, long-term viability. Specifically, estimates of return rates to breeding areas by adult females and natal areas by juvenile females are needed for planning effective recovery actions. We used a suite of polymorphic loci to genotype individuals and generated genetic profiles of nesting females and female offspring from nest materials collected between 1995 and 2016 in a ~170 km2 study area near Utqiaġvik, Alaska. We analyzed capture histories of genetically identified individuals to estimate breeding site fidelity, temporary emigration, and philopatry. From a sample of 365 nests, we found that breeding site fidelity of adult females was high (0.91 ± 0.07 SE), and temporary emigration was also high (0.77 ± 0.06) and annually variable (range 0.34-0.97). From egg shell remains of 124 hatched females, we observed 9 recaptures as nesting adults, suggesting that philopatry was also high (range 0.6-1.0). Given the relatively high rates of adult female breeding site fidelity and female philopatry that we estimated, management actions that reduce mortality of adult females and increase annual productivity are likely to help maintain the population of a few hundred breeding Steller’s eiders on the Arctic Coastal Plain of Alaska.

Background: This study explores sick leave changes 1-year pre- and post-treatment start for common mental health issues and their associations with self-reported symptoms, functioning, and health changes., Methods: Ninety-five employed patients, without previous disability benefits, underwent treatment at a public mental health outpatient clinic. Sick leave data was obtained from the Norwegian Labour and Welfare Administration. Symptoms, work/social functioning, and health quality were self-reported at treatment onset and completion., Results: Twelve months before starting treatment, only 6.3% were on sick leave, contrasting with 69.5% at treatment start. At post-treatment, 25% received work assessment allowance (WAA), 63% were off sick leave, and 12% were on sick leave. Sick leave days exhibited an inverted U-shape for non-WAA recipients. Those on sick leave post-treatment reported less improvement in symptoms and health, while the WAA group showed diminished work functioning enhancement., Discussion: Evaluating the effect mental health treatment has on sick leave is clearly affected by the timing of assessments. Treatment seems associated with improved sick leave outcomes compared with status at treatment start, but less so when compared with status one year before starting treatment. Also, a large group of patients went on to receive WAA, constituting a group in need of further longitudinal evaluations and interventions.

Background: This cross-sectional study aimed to explore health-related quality of life (HRQoL) in a large heterogeneous patient sample seeking outpatient treatment at a specialist mental health clinic., Method: A sample of 1947 patients with common mental disorders, including depressive-, anxiety-, personality-, hyperkinetic- and trauma-related disorders, completed the EuroQoL 5-Dimension 5-Level (EQ-5D-5L) to assess HRQoL. We investigated clinical and sociodemographic factors associated with the EQ-5D index and the EQ Visual Analogue Scale (VAS) using regression analyses., Results: The sample reported lower HRQoL compared with the general population and primary mental health care patients. Sick leave, disability pension, work assessment allowance, and more symptoms of anxiety and depression were associated with lower EQ-5D index and EQ VAS scores. Furthermore, being male, use of pain medication and having disorders related to trauma were associated with reduced EQ-5D index scores, while hyperkinetic disorders were associated with higher EQ-5D index scores., Conclusion: HRQoL of psychiatric outpatients is clearly impaired. This study indicated a significant association between employment status, symptom severity, and HRQoL in treatment-seeking outpatients. The findings highlight the importance of assessing HRQoL as part of routine clinical assessment., (© 2024. The Author(s).)

Objective: This study, the first to assess the reliability and validity of the Work and Social Assessment Scale (WSAS) in Norwegian routine mental health care, examines differences in functional impairment based on sick leave status, psychiatric diagnosis, and sex., Method: Including 3573 individuals from community mental health services (n1 = 1157) and a psychiatric outpatient clinic (n2 = 2416), exploratory factor analysis (EFA) on subsample 1 and confirmatory factor analysis (CFA) on subsample 2 were utilized to replicate the identified factor structure., Results: EFA supported a one-factor model, replicated by the CFA, with high internal consistency (α = .82, ω = .81). Patients on sick leave reported greater impairments in all aspects of functioning, except for relationships, with the largest effect size observed in the reported ability to work (d = .39). Psychiatric outpatients with major depressive disorder were associated with difficulties in home management, private leisure activities, and forming close relationships. Patients with attention-deficit/hyperactivity disorder reported less impairment than those with other disorders. Patients with personality disorders reported more relationship difficulties than those with PTSD, ADHD, and anxiety. No differences were found in the perceived ability to work between diagnoses. Women had a higher impairment in private leisure activities, whereas men reported more impairment in relationships., Conclusion: The demonstrated reliability and validity suggest that WSAS is a valuable assessment tool in Norwegian routine mental health care. Variations in functional impairment across sick leave status, sex, and psychiatric diagnoses highlight the importance of integrating routine assessments of functional impairment into mental health care practices. Future research should combine WSAS with register data to allow for a broader understanding of treatment effectiveness, emphasizing improvements in functional outcomes alongside symptom alleviation., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Lundqvist et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objective: Stepped care models are frameworks for mental health care systems in several countries. According to Norwegian guidelines, individuals with mental health problems of mild severity should be treated in community mental health services, moderate severity in specialist mental health services, while complex/severe problems are often a shared responsibility. This study investigated whether patients are allocated as intended., Methods: In a cross-sectional study, 4061 outpatients recruited from community- and specialist mental health services reported demographic variables, symptoms of anxiety/depression, functional impairment, health status, and sick leave status. The community sample consisted of two subsamples: mild/moderate problems and complex problems., Results: There was substantial overlap (80%-99%) of symptoms, impairment, and health between community- and specialist mental health services. More impairment, worse health, lower age, and being male were associated with treatment at specialist level compared to community mild/moderate. Better health, being in a relationship, and lower age were associated with specialized treatment compared to community complex group., Conclusion: The limited association between treatment level and symptoms and functional impairment reveals inconsistencies between treatment guidelines and clinical practice. How the existing organization affects patient outcomes and satisfaction should be investigated further.

There is a knowledge gap regarding clinically representative therapy given in routine settings, that is treatment as usual (TAU), for patients with common mental health problems (CMHP). This review and meta-analysis aimed to investigate what characterizes clinically representative therapy in Nordic routine clinics and meta-analyze the outcome of such treatment. Databases (PubMed, EMBASE, PsychINFO, and SveMed+) were searched for TAU, CMHP, and Nordic countries, together with backward and forward search in Scopus (7 November 2022). Studies were either randomized controlled trials (RCT) or open trials, using prospective study designs, examining heterogeneous outpatient groups in routine treatment. Within- and between-group effect sizes (ES), using random effects model, and moderator analyses were calculated. Eleven studies (n = 1,413), demonstrated a small to moderate within-group ES with high heterogeneity (g = 0.49, I 2  = 90%). ESs in RCTs were significantly smaller than in open trials. TAU had a marginally smaller ES (g = -0.21; adjusted for publication bias g = -0.06) compared to a broad set of clinical interventions. Clinically representative therapy in the Nordic countries demonstrated a wide variety of characteristics and also a marginally lower ES compared to other interventions. The ESs were smaller than other meta-analyses examining evidence-based treatments in routine treatment., (© 2023 The Authors. Scandinavian Journal of Psychology published by Scandinavian Psychological Associations and John Wiley & Sons Ltd.)

Background: Patient-reported outcome measures (PROM) provide clinicians with information about patients' perceptions of distress. When linked with treatment and diagnostic registers, new information on common mental health disorders (CMHD) and service use, may be obtained, which might be useful clinically and for policy decision-making. This study reports the prevalence of CMHD and their association with PROM severity. Further, subgroups of self-reported symptoms of depression and anxiety were examined, and their association with clinician-assessed mental disorders, functional impairment, and service use., Methods: In a cohort study of 2473 (63% female) outpatients, CMHD was examined with pre-treatment scores of self-reported depression and anxiety, and the number of assessments and psychotherapy appointments one year after treatment start. Factor mixture modelling (FMM) of anxiety and depression was used to examine latent subgroups., Results: Overall, 22% of patients with a CMHD had an additional comorbid mood/anxiety disorder, making the prevalence lower than expected. This comorbid group reported higher symptoms of anxiety and depression compared to patients with non-comorbid disorders. FMM revealed three classes: "anxiety and somatic depression" (33%), "mixed depression and anxiety" (40%), and "cognitive depression" (27%). The anxiety and somatic depression class was associated with older age, being single and on sick leave, higher probability of depressive-, anxiety-, and comorbid disorders, having more appointments and higher functional impairment. Although the cognitive depression class had less somatic distress than the mixed depression and anxiety class, they reported more functional impairment and had higher service use., Conclusion: The results show that higher levels of somatic symptoms of depression could both indicate higher and lower levels of functional impairment and service use. A group of patients with high somatic depression and anxiety was identified, with severe impairment and high service needs. By gaining insights into CMHD factors' relation with clinical covariates, self-reported risk factors of depression and anxiety could be identified for groups with different levels of aggravating life circumstances, with corresponding service needs. These could be important symptom targets in different groups of patients., (© 2023. The Author(s).)

Objective: Little is known about the effects of routine mental health care on return-to-work (RTW) outcomes. This systematic review aimed to summarize and evaluate the effects of clinical representative psychotherapy on RTW among patients with a common mental disorder (CMD), treated within public mental health care., Method: A systematic search was conducted using PubMed, PsycINFO, Embase, and SveMED+. Primary outcomes were RTW, sick leave status, or self-reported work functioning. Studies limited to specific treatments and/or specific patient groups were excluded., Results: Out of 1,422 records, only one article met the preregistered inclusion criteria. After broadening of criteria, a total of nine studies were included. Six were randomized controlled trials (RCT), two were register-based studies, and one was a quasi-experimental study. Descriptions of treatment duration and intensity of usual care were rarely specified but ranged from a few sessions to 3 years of psychotherapy. In the RCTs, two studies favored the intervention, one favored routine care, and three found no difference between conditions. Choice of outcomes differed greatly and included RTW rates (full or partial), number of days until RTW, change in sick leave status, and net days/months of work absence. Time points for outcome assessment also varied greatly from 3 months to 5 years after treatment., Conclusion: There is inconclusive evidence to establish to what extent routine mental healthcare is associated with improved RTW outcomes for patients with CMD. There is a need for more and better clinical trials and naturalistic studies detailing the content of routine treatment and its effect on RTW., Systematic Review Registration: This study was pre-registered at PROSPERO (CRD42022304967), https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022304967., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Lundqvist, Brattmyr, Lindberg, Havnen, Solem and Hjemdal.)

Purpose: Health-related quality of life (HRQoL) is an important aspect of mental health outcomes. There are few studies on HRQoL in heterogeneous patient populations seeking help at community mental health services. The aims of the study were to compare how HRQoL, measured by the EuroQol five dimensions with five levels (EQ-5D-5L), was distributed compared to other samples from national and international studies, and to explore what factors are associated with HRQoL., Methods: In a cross-sectional study, 1379 Norwegian outpatients reported their HRQoL before starting treatment. Associations with demographic variables, job status, socio-economic status, and use of pain medication were examined using multiple regression analysis., Results: Most of the sample, 70% to 90%, reported problems with usual activities, pain/discomfort, and anxiety/depression; 30% to 65% reported that these problems were of a moderate to extreme degree. Forty percent reported problems with mobility, and about 20% reported problems with self-care. The sample's HRQoL was considerably lower than the general population, and comparable to patient-groups from specialist mental health services. Originating from a developing country, lower level of education, lower yearly household income, being on sick leave or unemployed, and using pain medication were associated with lower HRQoL. Age, gender, and relationship status were not associated with HRQoL. This is the first study to simultaneously examine the unique contribution of these variables in one study., Conclusion: The most impacted domains of HRQoL were pain/discomfort, anxiety/depression, and usual activities. Lower HRQoL was associated with several socio-demographic factors and use of pain medication. These findings might have clinical implications and suggest that mental health professionals should routinely measure HRQoL in addition to symptom severity, to identify areas that should be targeted to improve HRQoL., (© 2023. The Author(s).)

Objective: The aim of this study was to test factor structure, measurement invariance, and concurrent validity of the nine item Patient Health Questionnaire-9 (PHQ-9) and the seven item Generalized Anxiety Disorder scale-7 (GAD-7) in a heterogeneous outpatient sample., Method: Outpatients completed the PHQ-9, GAD-7, and the Working Social Adjustment Scale (WSAS) before starting treatment. Study design was cross-sectional, with convenience sampling. The total sample consisted of 831 participants (61% women)., Results: Both PHQ-9 and GAD-7 demonstrated better fit statistics with two-factor and bifactor solutions consisting of a cognitive and somatic factor. Omega hierarchical was .78 for PHQ-9 and .81 for GAD-7. Both instruments achieved scalar invariance across gender, diagnosis, and comorbidity. However, the somatic factors demonstrated poor discriminant validity. These factors are not well separatable and risks being too similar if used together. The general factors of both instruments were most associated with functional impairment, although PHQ-9 demonstrated a stronger association with WSAS (γ = .74, r 2  = .62) than GAD-7 (γ = .54, r 2  = .32). Using latent mean difference, women and patients with comorbidity had significantly higher scores of both depression and anxiety., Conclusion: This study shows that the PHQ-9 and GAD-7 may be used as one-dimensional instruments in clinical settings. Tests for measurement invariance supported that both measures are understood and interpreted comparably across gender and diagnostic subgroups., (© 2022. The Author(s).)

Prevalence of influenza A virus (IAV) infections in northern-breeding waterfowl has previously been reported to reach an annual peak during late summer or autumn; however, little is known about IAV infection dynamics in waterfowl populations persisting at high-latitude regions such as Alaska, during winter. We captured mallards (Anas platyrhynchos) throughout the non-breeding season (August-April) of 2012-2015 in Fairbanks and Anchorage, the two largest cities in Alaska, to assess patterns of IAV infection and antibody production using molecular methods and a standard serologic assay. In addition, we used virus isolation, genetic sequencing, and a virus microneutralization assay to characterize viral subtypes and to evaluate the immune response of mallards captured on multiple occasions through time. We captured 923 mallards during three successive sampling years: Fairbanks in 2012/13 and 2013/14, and Anchorage in 2014/15. Prevalence varied by age, season, and year/site with high and relatively stable estimates throughout the non-breeding season. Infected birds were detected in all locations/seasons except early-winter in Fairbanks during 2013/14. IAVs with 17 combinations of hemagglutinin (H1-5, H7-9, H11, H12) and neuraminidase (N1-6, N8, N9) subtypes were isolated. Antibodies to IAVs were detected throughout autumn and winter for all sampling locations and years, however, seroprevalence was higher among adults and varied among years. Mallards exhibited individual heterogeneity with regard to immune response, providing instances of both seroconversion and seroreversion to detected viral subtypes. The probability that an individual transitioned from one serostatus to another varied by age, with juvenile mallards having higher rates of seroconversion and seroreversion than adults. Our study provides evidence that a diversity of IAVs circulate in populations of mallards wintering at urban locations in Alaska, and we suggest waterfowl wintering at high-latitudes may play an important role in maintenance of viruses across breeding seasons.

Influenza A Viruses (IAV) in nature must overcome shifting transmission barriers caused by the mobility of their primary host, migratory wild birds, that change throughout the annual cycle. Using a phylogenetic network of viral sequences from North American wild birds (2008-2011) we demonstrate a shift from intraspecific to interspecific transmission that along with reassortment, allows IAV to achieve viral flow across successive seasons from summer to winter. Our study supports amplification of IAV during summer breeding seeded by overwintering virus persisting locally and virus introduced from a wide range of latitudes. As birds migrate from breeding sites to lower latitudes, they become involved in transmission networks with greater connectivity to other bird species, with interspecies transmission of reassortant viruses peaking during the winter. We propose that switching transmission dynamics may be a critical strategy for pathogens that infect mobile hosts inhabiting regions with strong seasonality., (© 2016 John Wiley & Sons Ltd/CNRS.)

Background: The epidemiology of avian hematozoa at high latitudes is still not well understood, particularly in sub-Arctic and Arctic habitats, where information is limited regarding seasonality and range of transmission, co-infection dynamics with parasitic and viral agents, and possible fitness consequences of infection. Such information is important as climate warming may lead to northward expansion of hematozoa with unknown consequences to northern-breeding avian taxa, particularly populations that may be previously unexposed to blood parasites., Methods: We used molecular methods to screen blood samples and cloacal/oropharyngeal swabs collected from 1347 ducks of five species during May-August 2010, in interior Alaska, for the presence of hematozoa, Influenza A Virus (IAV), and IAV antibodies. Using models to account for imperfect detection of parasites, we estimated seasonal variation in prevalence of three parasite genera (Haemoproteus, Plasmodium, Leucocytozoon) and investigated how co-infection with parasites and viruses were related to the probability of infection., Results: We detected parasites from each hematozoan genus in adult and juvenile ducks of all species sampled. Seasonal patterns in detection and prevalence varied by parasite genus and species, age, and sex of duck hosts. The probabilities of infection for Haemoproteus and Leucocytozoon parasites were strongly positively correlated, but hematozoa infection was not correlated with IAV infection or serostatus. The probability of Haemoproteus infection was negatively related to body condition in juvenile ducks; relationships between Leucocytozoon infection and body condition varied among host species., Conclusions: We present prevalence estimates for Haemoproteus, Leucocytozoon, and Plasmodium infections in waterfowl at the interface of the sub-Arctic and Arctic and provide evidence for local transmission of all three parasite genera. Variation in prevalence and molecular detection of hematozoa parasites in wild ducks is influenced by seasonal timing and a number of host traits. A positive correlation in co-infection of Leucocytozoon and Haemoproteus suggests that infection probability by parasites in one or both genera is enhanced by infection with the other, or that encounter rates of hosts and genus-specific vectors are correlated. Using size-adjusted mass as an index of host condition, we did not find evidence for strong deleterious consequences of hematozoa infection in wild ducks.

Shrinking lakes were recently observed for several Arctic and Subarctic regions due to increased evaporation and permafrost degradation. Along with lake drawdown, these processes often boost aquatic chemical concentrations, potentially impacting trophic dynamics. In particular, elevated chemical levels may impact primary productivity, which may in turn influence populations of primary and secondary consumers. We examined trophic dynamics of 18 shrinking lakes of the Yukon Flats, Alaska, that had experienced pronounced increases in nutrient (>200 % total nitrogen, >100 % total phosphorus) and ion concentrations (>100 % for four major ions combined) from 1985-1989 to 2010-2012, versus 37 stable lakes with relatively little chemical change over the same period. We found that phytoplankton stocks, as indexed by chlorophyll concentrations, remained unchanged in both shrinking and stable lakes from the 1980s to 2010s. Moving up the trophic ladder, we found significant changes in invertebrate abundance across decades, including decreased abundance of five of six groups examined. However, these decadal losses in invertebrate abundance were not limited to shrinking lakes, occurring in lakes with stable surface areas as well. At the top of the food web, we observed that probabilities of lake occupancy for ten waterbird species, including adults and chicks, remained unchanged from the period 1985-1989 to 2010-2012. Overall, our study lakes displayed a high degree of resilience to multi-trophic cascades caused by rising chemical concentrations. This resilience was likely due to their naturally high fertility, such that further nutrient inputs had little impact on waters already near peak production.

Accurate estimates of demographic parameters are required to infer appropriate ecological relationships and inform management actions. Known-fate data from marked individuals are commonly used to estimate survival rates, whereas N-mixture models use count data from unmarked individuals to estimate multiple demographic parameters. However, a joint approach combining the strengths of both analytical tools has not been developed. Here we develop an integrated model combining known-fate and open N-mixture models, allowing the estimation of detection probability, recruitment, and the joint estimation of survival. We demonstrate our approach through both simulations and an applied example using four years of known-fate and pack count data for wolves (Canis lupus). Simulation results indicated that the integrated model reliably recovered parameters with no evidence of bias, and survival estimates were more precise under the joint model. Results from the applied example indicated that the marked sample of wolves was biased toward individuals with higher apparent survival rates than the unmarked pack mates, suggesting that joint estimates may be more representative of the overall population. Our integrated model is a practical approach for reducing bias while increasing precision and the amount of information gained from mark-resight data sets. We provide implementations in both the BUGS language and an R package.

Losses in lake area have been observed for several Arctic and Subarctic regions in recent decades, with unknown consequences for lake ecosystems. These reductions are primarily attributed to two climate-sensitive mechanisms, both of which may also cause changes in water chemistry: (i) increased imbalance of evaporation relative to inflow, whereby increased evaporation and decreased inflow act to concentrate solutes into smaller volumes; and (ii) accelerated permafrost degradation, which enhances sublacustrine drainage while simultaneously leaching previously frozen solutes into lakes. We documented changes in nutrients [total nitrogen (TN), total phosphorus (TP)] and ions (calcium, chloride, magnesium, sodium) over a 25 year interval in shrinking, stable, and expanding Subarctic lakes of the Yukon Flats, Alaska. Concentrations of all six solutes increased in shrinking lakes from 1985-1989 to 2010-2012, while simultaneously undergoing little change in stable or expanding lakes. This created a present-day pattern, much weaker or absent in the 1980s, in which shrinking lakes had higher solute concentrations than their stable or expanding counterparts. An imbalanced evaporation-to-inflow ratio (E/I) was the most likely mechanism behind such changes; all four ions, which behave semiconservatively and are prone to evapoconcentration, increased in shrinking lakes and, along with TN and TP, were positively related to isotopically derived E/I estimates. Moreover, the most conservative ion, chloride, increased >500% in shrinking lakes. Conversely, only TP concentration was related to probability of permafrost presence, being highest at intermediate probabilities. Overall, the substantial increases of nutrients (TN >200%, TP >100%) and ions (>100%) may shift shrinking lakes towards overly eutrophic or saline states, with potentially severe consequences for ecosystems of northern lakes., (© 2014 John Wiley & Sons Ltd.)

Shrubs have expanded in Arctic ecosystems over the past century, resulting in significant changes to albedo, ecosystem function, and plant community composition. Willow and rock ptarmigan (Lagopus lagopus, L. muta) and moose (Alces alces) extensively browse Arctic shrubs, and may influence their architecture, growth, and reproduction. Furthermore, these herbivores may alter forage plants in such a way as to increase the quantity and accessibility of their own food source. We estimated the effect of winter browsing by ptarmigan and moose on an abundant, early-successional willow (Salix alaxensis) in northern Alaska by comparing browsed to unbrowsed branches. Ptarmigan browsed 82-89% of willows and removed 30-39% of buds, depending on study area and year. Moose browsed 17-44% of willows and browsed 39-55% of shoots. Browsing inhibited apical dominance and activated axillary and adventitious buds to produce new vegetative shoots. Ptarmigan- and moose-browsed willow branches produced twice the volume of shoot growth but significantly fewer catkins the following summer compared with unbrowsed willow branches. Shoots on browsed willows were larger and produced 40-60% more buds compared to unbrowsed shoots. This process of shoot production at basal parts of the branch is the mechanism by which willows develop a highly complex "broomed" architecture after several years of browsing. Broomed willows were shorter and more likely to be re-browsed by ptarmigan, but not moose. Ptarmigan likely benefit from the greater quantity and accessibility of buds on previously browsed willows and may increase the carrying capacity of their own habitat. Despite the observed tolerance of willows to browsing, their vertical growth and reproduction were strongly inhibited by moose and ptarmigan. Browsing by these herbivores therefore needs to be considered in future models of shrub expansion in the Arctic.

Fires are the major natural disturbance in the boreal forest, and their frequency and intensity will likely increase as the climate warms. Terrestrial nutrients released by fires may be transported to boreal lakes, stimulating increased primary productivity, which may radiate through multiple trophic levels. Using a before-after-control-impact (BACI) design, with pre- and postfire data from burned and unburned areas, we examined effects of a natural fire across several trophic levels of boreal lakes, from nutrient and chlorophyll levels, to macroinvertebrates, to waterbirds. Concentrations of total nitrogen and phosphorus were not affected by the fire. Chlorophyll a levels were also unaffected, likely reflecting the stable nutrient concentrations. For aquatic invertebrates, we found that densities of three functional feeding groups did not respond to the fire (filterers, gatherers, scrapers), while two groups increased (shredders, predators). Amphipods accounted for 98% of shredder numbers, and we hypothesize that fire-mediated habitat changes may have favored their generalist feeding and habitat ecology. This increase in amphipods may, in turn, have driven increased predator densities, as amphipods were the most numerous invertebrate in our lakes and are commonly taken as prey. Finally, abundance of waterbird young, which feed primarily on aquatic invertebrates, was not affected by the fire. Overall, ecosystems of our study lakes were largely resilient to forest fires, likely due to their high initial nutrient concentrations and small catchment sizes. Moreover, this resilience spanned multiple trophic levels, a significant result for ecologically similar boreal regions, especially given the high potential for increased fires with future climate change.

We examined individual heterogeneity in survival and recruitment of female Pacific black brant (Branta bernicla nigricans) using frailty models adapted to a capture-mark-recapture context. Our main objectives were (1) to quantify levels of heterogeneity and examine factors affecting heterogeneity, and (2) model the effects of individual heterogeneity on harvest dynamics through matrix models. We used 24 years of data on brant marked and recaptured at the Tutakoke River colony, AK. Multievent models were fit as hidden Markov chain using program E-SURGE with an adequate overdispersion coefficient. Annual survival of individuals marked as goslings was heterogeneous among individuals and year specific with about 0.23 difference in survival between "high" (0.73)- and "low" (0.50)-quality individuals at average survival probability. Adult survival (0.85 ± 0.004) was homogeneous and higher than survival of both groups of juveniles. The annual recruitment probability was heterogeneous for brant >1-year-old; 0.56 (±0.21) and 0.31 (±0.03) for high- and low-quality individuals, respectively. Assuming equal clutch sizes for high- and low-quality individuals and that 80% of offspring were in the same quality class as the breeding female resulted in reproductive values about twice as high for high-quality individuals than low-quality individual for a given class of individuals producing differential contributions to population growth among groups. Differences in reproductive values greatly increased when we assumed high-quality individuals had larger clutch sizes. When we assumed that 50% of offspring were in the same quality class as their mothers and clutches were equal, differences in reproductive values between quality classes were greatly reduced or eliminated (breeders [BRs]). We considered several harvest scenarios using the assumption that 80% of offspring were in the same quality class as their mothers. The amount of compensation for harvest mortality declined as the proportion of high-quality individuals in the harvest increased, as differences in clutch sizes between groups decreased and as the proportion of BRs in the harvest increased. Synthesis and applications. Harvest at the same proportional level of the overall population can result in variable responses in population growth rate when heterogeneity is present in a population. λ was <1.0 under every scenario when harvest rates were >10%, and heterogeneity caused as much as +2% difference in growth rates at the highest levels of proportional harvest for low-quality individuals and the greatest differences in qualities between classes of individuals, a critical difference for a population with λ near 1.0 such as the brant. We observed less response in overall survival in the presence of heterogeneity because we did not observe heterogeneity in the annual survival of BRs. This analysis provides a comprehensive view of overall compensation at the population level and also constitutes the first example of a survival-recruitment model with heterogeneity. Individual heterogeneity should be more explicitly considered in harvest management of vertebrates.

The Prairie Pothole Region (PPR) is the primary breeding region for most species of North American dabbling ducks (Anas spp.). Conservation of these species is guided in part by knowledge of relationships between nest survival probability and habitat features. Positive relationships between duck nest survival and amount and configuration of herbaceous perennial vegetation have been observed in previous studies, but these 2- to 4-year studies might not have adequately characterized the temporal effect of wet-dry episodes on nest survival. Over an eight-year period, we studied nest survival of five species of ducks in the PPR relative to spatial and temporal variation in pond density, primary productivity, and hydrologic status of wetlands, soil, and vegetation on 52 study sites selected to span a gradient of spatial variation in proportion of herbaceous perennial vegetation and in number of wetland basins. We observed the fate of 12 754 nests. Consistent with past studies, 90% of nests that failed to hatch were destroyed by predators. Nest survival probability was positively related to current-year pond density and primary productivity, negatively related to pond density and primary productivity during the previous two years, and positively related to the number of wetland basins on the study site. Predicted relationships between nest survival and proportion or configuration of herbaceous perennial vegetation in the surrounding landscape were not supported. For mallard (Anas platyrhynchos), median estimated nest survival probability ranged from 0.02 (SE = 0.01) to 0.22 (SE = 0.02). Estimated nest survival was greatest on sites with numerous wetland basins that had transitioned from dry, unproductive conditions to wet, productive conditions in the previous 1-2 years. Our results were consistent with time-lagged responses of food webs to resource pulses in a broad array of ecosystems. Our study highlighted the importance of wetland basins and wet-dry episodes to duck nest survival in the PPR. Current habitat conservation efforts focus on landscapes with numerous wetland basins and a high proportion of herbaceous perennial vegetation. Our results suggest that future conservation efforts should focus on preserving high-density wetland complexes across as large a geographic extent as possible even in cropland-dominated landscapes.

Climate-induced phenological shifts can influence population, evolutionary, and ecological dynamics, but our understanding of these phenomena is hampered by a lack of long-term demographic data. We use a multi-decade census of 5 salmonid species representing 14 life histories in a warming Alaskan stream to address the following key questions about climate change and phenology: How consistent are temporal patterns and drivers of phenology for similar species and alternative life histories? Are shifts in phenology associated with changes in phenotypic variation? How do phenological changes influence the availability of resource subsidies? For most salmonid species, life stages, and life histories, freshwater temperature influences migration timing--migration events are occurring earlier in time (mean = 1.7 days earlier per decade over the 3-5 decades), and the number of days over which migration events occur is decreasing (mean = 1.5 days per decade). Temporal trends in migration timing were not correlated with changes in intra-annual phenotypic variation, suggesting that these components of the phenotypic distribution have responded to environmental change independently. Despite commonalities across species and life histories, there was important biocomplexity in the form of disparate shifts in migration timing and variation in the environmental factors influencing migration timing for alternative life history strategies in the same population. Overall, adult populations have been stable during these phenotypic and environmental changes (λ ≈ 1.0), but the temporal availability of salmon as a resource in freshwater has decreased by nearly 30 days since 1971 due to changes in the median date of migration timing and decreases in intra-annual variation in migration timing. These novel observations advance our understanding of phenological change in response to climate warming, and indicate that climate change has influenced the ecology of salmon populations, which will have important consequences for the numerous species that depend on this resource.

1. Patterns of temporary emigration (associated with non-breeding) are important components of variation in individual quality. Permanent emigration from the natal area has important implications for both individual fitness and local population dynamics. 2. We estimated both permanent and temporary emigration of black brent geese (Branta bernicla nigricans Lawrence) from the Tutakoke River colony, using observations of marked brent geese on breeding and wintering areas, and recoveries of ringed individuals by hunters. We used the likelihood developed by Lindberg, Kendall, Hines & Anderson 2001 (Combining band recovery data and Pollock's robust design to model temporary and permanent emigration. Biometrics, 57, 273-281) to assess hypotheses and estimate parameters. 3. Temporary emigration (the converse of breeding) varied among age classes up to age 5, and differed between individuals that bred in the previous years vs. those that did not. Consistent with the hypothesis of variation in individual quality, individuals with a higher probability of breeding in one year also had a higher probability of breeding the next year. 4. Natal fidelity of females ranged from 0.70 +/- 0.07-0.96 +/- 0.18 and averaged 0.83. In contrast to Lindberg et al. (1998), we did not detect a relationship between fidelity and local population density. Natal fidelity was negatively correlated with first-year survival, suggesting that competition among individuals of the same age for breeding territories influenced dispersal. Once females nested at the Tutakoke River, colony breeding fidelity was 1.0. 5. Our analyses show substantial variation in individual quality associated with fitness, which other analyses suggest is strongly influenced by early environment. Our analyses also suggest substantial interchange among breeding colonies of brent geese, as first shown by Lindberg et al. (1998).

Nest-site selection is an important determinant of individual fitness in birds. Understanding what information individuals use to choose nest sites is therefore important for understanding the evolution of nest-site selection, the dynamics of populations, and the conservation of species. We used five years of mark-recapture data for Mountain Bluebirds (Sialia currucoides) to examine how dispersal probability and nest-site selection vary with potential cues of nest-site quality. Dispersal distance between breeding seasons and nest-site selection were modeled as a function of personal reproductive success, conspecific density, conspecific reproductive success, and habitat type. Between years, the dispersal probability was related to personal reproductive success, not conspecific information, and individuals fledging fewer young dispersed longer distances. For dispersing individuals, the probability that a nest site was selected in year i was negatively related to distance from the nest site selected in year i - 1 for all age and sex classes, and positively related to conspecific density and reproductive success in year i - 1 for both second-year (SY) and after-hatch-year (AHY) females. However, nest-site selection in year i was more strongly related to conspecific density in year i- 1 for hatch-year (HY) females and was much more strongly related to the reproductive success of conspecifics in year i - 1 for AHY females. Nest-site selection of HY and AHY males was not consistently related to the metrics of conspecific information, but we suspect that relationships were obscured by competitive interactions. We found no evidence indicating that individuals respond differently to conspecific information at longer distances, suggesting that individuals limit dispersal to areas where they have prior knowledge. We predict that these patterns of nest-site selection will allow birds to loosely track nest-site quality and maintain an ideal free distribution, where average fitness is equal in all habitat types.

Populations of Greater Sage-Grouse (Centrocercus urophasianus) have declined by 69-99% from historic levels, and information on population dynamics of these birds at a landscape scale is essential to informed management. We examined the relationships between hen survival and a suite of landscape-scale habitat and environmental conditions. We radio-marked 237 female Sage-Grouse and measured 426 vegetation plots during 2001-2004 at four sites in a 3200-km2 landscape in north-central Montana, USA. We used program MARK to model monthly survival rates for 11 seasonal intervals. There was strong support for the best-approximating model (AICc weight = 0.810), which indicated that (1) hen survival varied by season within years and by year within seasons, (2) nesting hens had higher nesting-season survival than non-nesting hens, and (3) individuals at one site had lower hunting-season survival than at other sites. We observed considerable variation in hen survival. Process variation was 0.255, with an expected range of annual survival of 0.12 to 1.0. The ratio of process to total variation was 0.999, indicating that observed variation was real and not attributable to sampling variation. We observed a nearly fourfold difference in maximum and minimum annual survival, ranging from 0.962 +/- 0.024 (mean +/- SE) for nesting hens in 2001-2002 to 0.247 +/- 0.050) for non-nesters in 2003-2004. Low annual survival in 2003 resulted from the compounded effects of a West Nile virus outbreak in August and a severe winter in 2003-2004. Increased hen mortality associated with severe winter weather contrasts with prior beliefs that Sage-Grouse populations are typically unaffected by winter weather conditions and underscores the importance of protecting winter sagebrush (Artemisia spp.) habitats.

Questions about individual variation in "quality" and fitness are of great interest to evolutionary and population ecologists. Such variation can be investigated using either a random effects approach or an approach that relies on identifying observable traits that are themselves correlated with fitness components. We used the latter approach with data from 1,925 individual females of three species of ducks (tufted duck, Aythya fuligula; common pochard, Aythya ferina; northern shoveler, Anas clypeata) sampled on their breeding grounds at Engure Marsh, Latvia, for over 15 years. Based on associations with reproductive output, we selected two traits, one morphological (relative body condition) and one behavioral (relative time of nesting), that can be used to characterize individual females over their lifetimes. We then asked whether these traits were related to annual survival probabilities of nesting females. We hypothesized quadratic, rather than monotonic, relationships based loosely on ideas about the likely action of stabilizing selection on these two traits. Parameters of these relationships were estimated directly using ultrastructural models embedded within capture-recapture-band-recovery models. Results provided evidence that both traits were related to survival in the hypothesized manner. For all three species, females that tended to nest earlier than the norm exhibited the highest survival rates, but very early nesters experienced reduced survival and late nesters showed even lower survival. For shovelers, females in average body condition showed the highest survival, with lower survival rates exhibited by both heavy and light birds. For common pochard and tufted duck, the highest survival rates were associated with birds of slightly above-average condition, with somewhat lower survival for very heavy birds and much lower survival for birds in relatively poor condition. Based on results from this study and previous work on reproduction, we conclude that nest initiation date and body condition covary with both reproductive and survival components of fitness. These associations lead to a positive covariance of these two fitness components within individuals and to the conclusion that these two traits are indeed correlates of individual quality.

Capture-recapture models are widely used to estimate demographic parameters of marked populations. Recently, this statistical theory has been extended to modeling dispersal of open populations. Multistate models can be used to estimate movement probabilities among subdivided populations if multiple sites are sampled. Frequently, however, sampling is limited to a single site. Models described by Burnham (1993, in Marked Individuals in the Study of Bird Populations, 199-213), which combined open population capture-recapture and band-recovery models, can be used to estimate permanent emigration when sampling is limited to a single population. Similarly, Kendall, Nichols, and Hines (1997, Ecology 51, 563-578) developed models to estimate temporary emigration under Pollock's (1982, Journal of Wildlife Management 46, 757-760) robust design. We describe a likelihood-based approach to simultaneously estimate temporary and permanent emigration when sampling is limited to a single population. We use a sampling design that combines the robust design and recoveries of individuals obtained immediately following each sampling period. We present a general form for our model where temporary emigration is a first-order Markov process, and we discuss more restrictive models. We illustrate these models with analysis of data on marked Canvasback ducks. Our analysis indicates that probability of permanent emigration for adult female Canvasbacks was 0.193 (SE = 0.082) and that birds that were present at the study area in year i - 1 had a higher probability of presence in year i than birds that were not present in year i - 1.