Evidence that Pacific tuna mercury levels are driven by marine methylmercury production and anthropogenic inputs.

Pacific Ocean tuna is among the most-consumed seafood products but contains relatively high levels of the neurotoxin methylmercury. Limited observations suggest tuna mercury levels vary in space and time, yet the drivers are not well understood. Here, we map mercury concentrations in skipjack tuna across the Pacific Ocean and build generalized additive models to quantify the anthropogenic, ecological, and biogeochemical drivers. Skipjack mercury levels display a fivefold spatial gradient, with maximum concentrations in the northwest near Asia, intermediate values in the east, and the lowest levels in the west, southwest, and central Pacific. Large spatial differences can be explained by the depth of the seawater methylmercury peak near low-oxygen zones, leading to enhanced tuna mercury concentrations in regions where oxygen depletion is shallow. Despite this natural biogeochemical control, the mercury hotspot in tuna caught near Asia is explained by elevated atmospheric mercury concentrations and/or mercury river inputs to the coastal shelf. While we cannot ignore the legacy mercury contribution from other regions to the Pacific Ocean (e.g., North America and Europe), our results suggest that recent anthropogenic mercury release, which is currently largest in Asia, contributes directly to present-day human mercury exposure.

Energetic connectivity of diverse elasmobranch populations - implications for ecological resilience.

Understanding the factors shaping patterns of ecological resilience is critical for mitigating the loss of global biodiversity. Throughout aquatic environments, highly mobile predators are thought to serve as important vectors of energy between ecosystems thereby promoting stability and resilience. However, the role these predators play in connecting food webs and promoting energy flow remains poorly understood in most contexts. Using carbon and nitrogen isotopes, we quantified the use of several prey resource pools (small oceanic forage, large oceanics, coral reef, and seagrass) by 17 species of elasmobranch fishes (n = 351 individuals) in The Bahamas to determine their functional diversity and roles as ecosystem links. We observed remarkable functional diversity across species and identified four major groups responsible for connecting discrete regions of the seascape. Elasmobranchs were responsible for promoting energetic connectivity between neritic, oceanic and deep-sea ecosystems. Our findings illustrate how mobile predators promote ecosystem connectivity, underscoring their functional significance and role in supporting ecological resilience. More broadly, strong predator conservation efforts in developing island nations, such as The Bahamas, are likely to yield ecological benefits that enhance the resilience of marine ecosystems to combat imminent threats such as habitat degradation and climate change.

A longitudinal study of perfectionism and orthorexia in exercisers.

Research suggests that trait perfectionism and perfectionistic self-presentation are related to orthorexia - a pathological obsession with correct nutrition. However, no studies have examined these relationships over time or compared the influence of the two aspects of perfectionism on orthorexia. In the present study we sought to address these two issues. Gym members who engaged in high degrees of exercise were recruited via social media platforms. They completed an online questionnaire that included the Multidimensional Perfectionism Scale-Short Form, Perfectionistic Self-Presentation Scale, and the Eating Habits Questionnaire on two occasions: 177 participants (Mean age = 31.6 years) initially completed the questionnaire and 82 completed the questionnaire six weeks later. A series of multiple regression analyses revealed that (i) trait perfectionism predicted an increase in orthorexia symptomatology over time with socially prescribed perfectionism and other-oriented perfectionism unique predictors of orthorexia, (ii) perfectionistic self-presentation predicted orthorexia over time with nondisplay of imperfection a unique predictor of orthorexia, and (iii) when considered alongside each other, only trait dimensions of perfectionism were unique predictors of orthorexia. The present study provides further evidence that perfectionism is related to orthorexia. In addition, the study also provides preliminary evidence that more engrained trait aspects of perfectionism are more predictive of orthorexia over time than the self-presentational aspects of perfectionism.

A daily diary study of primary appraisals, emotional exhaustion, and turnover intentions in sport coaches.

Cognitive-motivational-relational theory asserts that stress is a dynamic process, during which daily fluctuations in mediating processes (primary appraisals) can explain a range of ill-being and performance related outcomes. We tested this idea using a daily diary study to examine the relationships between primary appraisals, emotional exhaustion, and turnover intentions in sport coaches. Forty-four sport coaches (61% male; Mage = 34.98 years) completed an online questionnaire twice per day for five days. The findings of within-person analyses indicated that hourly harm appraisals positively predicted momentary emotional exhaustion over the diary period (ß = .30, p < .05). Additionally, emotional exhaustion positively predicted coaches' job turnover intentions (ß = .18, p < .05). The findings offer unique insight into the cognitive-motivational-relational theory of stress and emotion by illustrating how exhaustion and turnover intentions may be intensified as a function of primary appraisals experienced during the working day.

Trophic Dynamics and Feeding Ecology of Skipjack Tuna (Katsuwonus pelamis) off Eastern and Western Taiwan.

The skipjack tuna (Katsuwonus pelamis) is a mesopredator fish species with seasonal abundance in waters off Taiwan. Regional ecological and life-history information has been historically lacking for this species. In recent years, stable isotope analysis (SIA) of carbon and nitrogen has been used to assess predator feeding ecology and broader ecosystem trophic dynamics. This study evaluated comparative skipjack feeding ecology in distinct regions off Taiwan, combining traditional stomach content analysis with SIA of individuals off western (n = 43; 2020) and eastern (n = 347; 2012-2014 and n = 167; 2020) Taiwan. The stomach content analysis showed the most important prey to be ponyfish (Photopectoralis bindus) in western Taiwan and epipelagic squids (Myopsina spp.) and carangids (Decapterus macrosoma;) in eastern Taiwan from 2012 to 2014 and epipelagic carangids (Decapterus spp.) and flying fishes (Cheilopogon spp.) in eastern Taiwan in 2020, suggesting that the skipjack tuna is a generalist predator across regions. In contrast, time-integrated diet estimates from Bayesian mixing models indicated the importance of cephalopods and crustaceans as prey, potentially demonstrating more mesopelagic feeding in less productive waters during skipjack migrations outside the study regions. Skipjack off western Taiwan had a slightly higher estimated trophic position than in the waters off eastern Taiwan, potentially driven by the varying nutrient-driven pelagic food web structures. Skipjack SI values increased with body size off eastern Taiwan but not in western waters, suggesting that opportunistic predation can still result in different predator-prey size dynamics between regions.

Athlete Burnout Symptoms Are Increasing: A Cross-Temporal Meta-Analysis of Average Levels From 1997 to 2019.

With the increasing prevalence of mental health difficulties in sport, athletes may be at greater risk of burnout than ever before. In the present study, we tested this possibility by examining whether average athlete burnout levels have changed over the past 2 decades, from 1997 to 2019. A literature search returned 91 studies (N = 21,012) and 396 effect sizes. Findings from cross-temporal meta-analysis suggested that burnout symptoms have increased over the past 2 decades. Specifically, we found that athletes' mean levels of reduced sense of athletic accomplishment and sport devaluation have increased. As burnout symptoms are now typically higher among athletes than in the past, we can expect more athletes to be prone to the negative effects of burnout. Sport is therefore in urgent need of prevention and intervention strategies to stop and reverse this trend.

Perfectionistic self-presentation and orthorexia in exercisers.

PURPOSE: The present study aimed to provide the first examination of whether perfectionistic self-presentation-an interpersonal expression of perfectionism-is related to orthorexia. METHODS: We recruited a sample of 150 exercisers (Mean age = 27.7 years). Participants completed the Perfectionistic Self-Presentation Scale and the ORTO-15 on a single occasion. RESULTS: Two dimensions of perfectionistic self-presentation-perfectionistic self-promotion and nondisplay of imperfection-showed significant positive correlations with orthorexia. In addition, in multiple regression analyses controlling for the overlap between dimensions, perfectionistic self-promotion emerged as the strongest and only significant predictor of orthorexia. CONCLUSION: Perfectionistic self-presentation is positively associated with orthorexia in exercisers. Perfectionistic self-promotion-a need to portray an image of perfection to others-is primarily responsible for this relationship. LEVEL OF EVIDENCE: Cross-sectional study, Level V.

Development of perfectionism in junior athletes: Examination of actual and perceived parental perfectionism.

Initial research suggests that parental perfectionism is central to the development of athlete perfectionism. However, it is unclear whether perceived or actual parental perfectionism is most important. The present study aimed to address this issue in two ways. First, we re-examined the predictive ability of actual versus perceived parental perfectionism on athlete perfectionism. Second, for the first time, we tested whether perceived parental perfectionism mediated the relationship between actual parental perfectionism and athlete perfectionism. A sample of 150 junior athletes and their parents completed measures of perfectionism (perfectionistic strivings and perfectionistic concerns). Junior athletes completed two measures, one of their own perfectionism and one of perceptions of their parents' perfectionism. Parents completed one measure of their own perfectionism. Regression analyses showed that perceived parental perfectionism predicted athlete perfectionism over and above actual parental perfectionism. Mediation analyses provided support for our proposed model. Overall, the findings suggest that both actual and perceived parental perfectionism are important in the development of perfectionism in junior athletes.

Implicit and explicit attitudes towards sport among young elite athletes with high versus low burnout symptoms.

The development of cynical attitudes towards elite sport is a core symptom of athlete burnout and has been associated with dropout from elite sport. To date, this phenomenon has mainly been studied by investigating explicit attitudes towards sport, whereas athletes' automatic evaluations (i.e. implicit attitudes) that have been shown to influence behavior as well were not considered. This study aimed to compare explicit and implicit attitudes towards sport of young elite athletes with high (N = 24) versus low (N = 26) burnout symptoms. Using self-reported measures, general and athlete burnout symptoms were assessed. Additionally, a single-target implicit association test was administered to examine participants' automatic evaluation of sport. Statistical analysis revealed greater emotional/physical exhaustion and sport devaluation in athletes reporting high compared to low burnout symptoms. Implicit attitudes towards sport did not significantly differ between the groups. Furthermore, no significant correlations were observed between different athlete burnout symptoms and implicit attitudes. Athletes with high burnout symptoms show a tendency to explicitly detach themselves from sport, thus fostering sport devaluation as a core symptom of athlete burnout. However, this process does not seem to be reflected in their implicit attitudes towards sport.

Stable isotope analysis reveals ontogenetic feeding shifts in Pacific blue marlin (Makaira nigricans) off eastern Taiwan.

To gain a better understanding of the trophic ecology of Pacific blue marlin Makaira nigricans off eastern Taiwan, nitrogen and carbon stable isotopes (δ15 N and δ13 C) and Bayesian mixing models were used to explore trophic dynamics and potential ontogenetic feeding shifts across M. nigricans of different size classes. Makaira nigricans samples from east of Taiwan (n = 213) and Palau (n = 37), as well as their prey (n = 70), were collected during 2012 and 2013. Results indicated increases in δ15 N with size, with values of larger size classes (> 200 cm eye-to-fork length; LEF ) significantly higher than those < 200 cm LEF . Values of δ13 C were negatively correlated with size. Makaira nigricans > 200 cm LEF had the highest estimated trophic position (4.44) and also exhibited ontogenetic changes in trophic position. Large M. nigricans fed more on dolphinfish Coryphaena hippurus and hairtail Trichiurus lepturus, while smaller M. nigricans consumed smaller forage fish (e.g., moonfish Mene maculata) and cephalopods. These changes may relate to greater swimming speeds and vertical habitat use in larger M. nigricans, allowing capture and consumption of larger prey items at higher trophic positions. The high trophic level of M. nigricans east of Taiwan confirms its important role as an apex predator in marine food webs and how ecological role changes with size.

Perfectionism and Precompetition Emotions in Youth Footballers: A Three-Wave Longitudinal Test of the Mediating Role of Perfectionistic Cognitions.

Perfectionism is related to precompetition emotions in athletes. However, it is unclear why this is the case. In the present study, the authors sought to determine whether perfectionistic cognitions explain this relationship and mediate the relationships between self-oriented perfectionism (SOP), socially prescribed perfectionism (SPP), and general precompetition emotions and multidimensional anxiety and anger. The authors adopted a three-wave longitudinal design and examined between- and within-person effects in a sample of 352 youth footballers (Mage = 14.03 years, SD = 2.30). At the between-person level, perfectionistic cognitions mediated the relationships between SOP, SPP, and all general precompetition emotions plus multidimensional anxiety and anger. At the within-person level, perfectionistic cognitions mediated the relationships between SOP, SPP, and general anxiety and anger plus multidimensional anxiety and anger. Our findings imply that athletes higher in SOP and SPP experience more anxiety and anger when the frequency of perfectionistic cognitions increases in the lead-up to competition.

Development of Perfectionism in Junior Athletes: A Three-Sample Study of Coach and Parental Pressure.

Perfectionism predicts cognitions, emotions, and behaviors in sport. Nonetheless, our understanding of the factors that influence its development is limited. The authors sought to address this issue by examining the role of coach and parental pressure in the development of perfectionism in sport. Using 3 samples of junior athletes (16-19 years; cross-sectional n = 212, 3-month longitudinal n = 101, and 6-month longitudinal n = 110), the authors examined relations between coach pressure to be perfect, parental pressure to be perfect, perfectionistic strivings, and perfectionistic concerns. Mini meta-analysis of the combined cross-sectional data (N = 423) showed that both coach pressure and parental pressure were positively correlated with perfectionistic strivings and perfectionistic concerns. In contrast, longitudinal analyses showed that only coach pressure predicted increased perfectionistic strivings and perfectionistic concerns over time. Overall, our findings provide preliminary evidence that coaches may play a more important role in the development of junior athletes' perfectionism than parents.

Mercury Stable Isotopes Reveal Influence of Foraging Depth on Mercury Concentrations and Growth in Pacific Bluefin Tuna.

Pelagic ecosystems are changing due to environmental and anthropogenic forces, with uncertain consequences for the ocean's top predators. Epipelagic and mesopelagic prey resources differ in quality and quantity, but their relative contribution to predator diets has been difficult to track. We measured mercury (Hg) stable isotopes in young (<2 years old) Pacific bluefin tuna (PBFT) and their prey species to explore the influence of foraging depth on growth and methylmercury (MeHg) exposure. PBFT total Hg (THg) in muscle ranged from 0.61 to 1.93 µg g-1 dw (1.31 µg g-1 dw ±0.37 SD; 99% ± 6% MeHg) and prey ranged from 0.01 to 1.76 µg g-1 dw (0.13 µg g-1 dw ±0.19 SD; 85% ± 18% MeHg). A systematic decrease in prey δ202Hg and Δ199Hg with increasing depth of occurrence and discrete isotopic signatures of epipelagic prey (δ202Hg: 0.74 to 1.49‰; Δ199Hg: 1.76-2.96‰) and mesopelagic prey (δ202Hg: 0.09 to 0.90‰; Δ199Hg: 0.62-1.95‰) allowed the use of Hg isotopes to track PBFT foraging depth. An isotopic mixing model was used to estimate the dietary proportion of mesopelagic prey in PBFT, which ranged from 17% to 55%. Increased mesopelagic foraging was significantly correlated with slower growth and higher MeHg concentrations in PBFT. The slower observed growth rates suggest that prey availability and quality could reduce the production of PBFT biomass.

Assessing niche width of endothermic fish from genes to ecosystem.

Endothermy in vertebrates has been postulated to confer physiological and ecological advantages. In endothermic fish, niche expansion into cooler waters is correlated with specific physiological traits and is hypothesized to lead to greater foraging success and increased fitness. Using the seasonal co-occurrence of three tuna species in the eastern Pacific Ocean as a model system, we used cardiac gene expression data (as a proxy for thermal tolerance to low temperatures), archival tag data, and diet analyses to examine the vertical niche expansion hypothesis for endothermy in situ. Yellowfin, albacore, and Pacific bluefin tuna (PBFT) in the California Current system used more surface, mesopelagic, and deep waters, respectively. Expression of cardiac genes for calcium cycling increased in PBFT and coincided with broader vertical and thermal niche utilization. However, the PBFT diet was less diverse and focused on energy-rich forage fishes but did not show the greatest energy gains. Ecosystem-based management strategies for tunas should thus consider species-specific differences in physiology and foraging specialization.

Perfectionism predicts injury in junior athletes: Preliminary evidence from a prospective study.

According to the stress-injury model (Williams & Andersen, 1998), personality factors predisposing athletes to elevated levels of stress may increase the risk of injury. As perfectionism has been associated with chronic stress, it may be one such personality factor. So far, however, no study has investigated the relationships between perfectionism and injury utilising a prospective design. Therefore, the present study examined perfectionistic strivings, perfectionistic concerns and injury in 80 junior athletes from team and individual sports (mean age 17.1 years; range 16-19 years) over 10 months of active training. The results of logistic regression analyses showed that perfectionism positively predicted injury, but only perfectionistic concerns emerged as a significant positive predictor. The likelihood of sustaining an injury was increased by over two times for each 1 SD increase in perfectionistic concerns. The findings suggest that perfectionistic concerns may be a possible factor predisposing athletes to an increased risk of injury.

Cross-Sectional and Longitudinal Associations Between Athlete Burnout, Insomnia, and Polysomnographic Indices in Young Elite Athletes.

Few studies have examined the association between sleep and burnout symptoms in elite athletes. We recruited 257 young elite athletes (Mage = 16.8 years) from Swiss Olympic partner schools. Of these, 197 were reassessed 6 months later. Based on the first assessment, 24 participants with clinically relevant burnout symptoms volunteered to participate in a polysomnographic examination and were compared with 26 (matched) healthy controls. Between 12% and 14% of young elite athletes reported burnout symptoms of potential clinical relevance, whereas 4-11% reported clinically relevant insomnia symptoms. Athletes with clinically relevant burnout symptoms reported significantly more insomnia symptoms, more dysfunctional sleep-related cognitions, and spent less time in bed during weeknights (p < .05). However, no significant differences were found for objective sleep parameters. A cross-lagged panel analysis showed that burnout positively predicted self-reported insomnia symptoms. Cognitive-behavioral interventions to treat dysfunctional sleep-related cognitions might be a promising measure to reduce subjective sleep complaints among young elite athletes.

Assessing Fukushima-Derived Radiocesium in Migratory Pacific Predators.

The 2011 release of Fukushima-derived radionuclides into the Pacific Ocean made migratory sharks, teleosts, and marine mammals a source of speculation and anxiety regarding radiocesium (134+137Cs) contamination, despite a lack of actual radiocesium measurements for these taxa. We measured radiocesium in a diverse suite of large predators from the North Pacific Ocean and report no detectable (i.e., ≥ 0.1 Bq kg-1 dry wt) Fukushima-derived 134Cs in all samples, except in one olive ridley sea turtle (Lepidochelys olivacea) with trace levels (0.1 Bq kg-1). Levels of 137Cs varied within and across taxa, but were generally consistent with pre-Fukushima levels and were lower than naturally occurring 40K by one to one to two orders of magnitude. Predator size had a weaker effect on 137Cs and 40K levels than tissue lipid content. Predator stable isotope values (δ13C and δ15N) were used to infer recent migration patterns, and showed that predators in the central, eastern, and western Pacific should not be assumed to accumulate detectable levels of radiocesium a priori. Nondetection of 134Cs and low levels of 137Cs in diverse marine megafauna far from Fukushima confirms negligible increases in radiocesium, with levels comparable to those prior to the release from Fukushima. Reported levels can inform recently developed models of cesium transport and bioaccumulation in marine species.

Perfectionism and training distress in junior athletes: a longitudinal investigation.

Perfectionistic athletes may train harder and for longer than non-perfectionistic athletes, leaving them susceptible to elevated levels of training distress. So far, however, no study has investigated the relationships between perfectionism and training distress, a key indicator of overtraining syndrome. Furthermore, no study has determined psychological predictors of overtraining syndrome. Using a two-wave design, the present study examined perfectionistic strivings, perfectionistic concerns and training distress in 141 junior athletes (mean age = 17.3 years, range = 16-19 years) over 3 months of active training. Multiple regression analyses were employed to test cross-sectional and longitudinal relationships between perfectionism and training distress. In all analyses, perfectionism emerged as a significant predictor, but strivings and concerns showed differential relationships. When the cross-sectional relationships were regarded, perfectionistic concerns positively predicted training distress (P < .001), whereas perfectionistic strivings negatively predicted training distress (P < .01). When the longitudinal relationships were regarded, only perfectionistic concerns predicted increases in training distress (P < .05), whereas perfectionistic strivings did not (P > .05). The findings suggest that sports scientists who wish to identify athletes at risk of overtraining syndrome may monitor athletes' perfectionistic concerns as a possible risk factor.

Perfectionism and eating disorder symptoms in female university students: the central role of perfectionistic self-presentation.

PURPOSE: Numerous studies have found perfectionism to show positive relations with eating disorder symptoms, but so far no study has examined whether perfectionistic self-presentation can explain these relations or whether the relations are the same for different eating disorder symptom groups. METHODS: A sample of 393 female university students completed self-report measures of perfectionism (self-oriented perfectionism, socially prescribed perfectionism), perfectionistic self-presentation (perfectionistic self-promotion, nondisplay of imperfection, nondisclosure of imperfection), and three eating disorder symptom groups (dieting, bulimia, oral control). In addition, students reported their weight and height so that their body mass index (BMI) could be computed. RESULTS: Results of multiple regression analyses controlling for BMI indicated that socially prescribed perfectionism positively predicted all three symptom groups, whereas self-oriented perfectionism positively predicted dieting only. Moreover, perfectionistic self-presentation explained the positive relations that perfectionism showed with dieting and oral control, but not with bulimia. Further analyses indicated that all three aspects of perfectionistic self-presentation positively predicted dieting, whereas only nondisclosure of imperfection positively predicted bulimia and oral control. Overall, perfectionistic self-presentation explained 10.4-23.5 % of variance in eating disorder symptoms, whereas perfectionism explained 7.9-12.1 %. CONCLUSIONS: The findings suggest that perfectionistic self-presentation explains why perfectionistic women show higher levels of eating disorder symptoms, particularly dieting. Thus, perfectionistic self-presentation appears to play a central role in the relations of perfectionism and disordered eating and may warrant closer attention in theory, research, and treatment of eating and weight disorders.

Contaminated Marine Sediments As a Source of Cesium Radioisotopes for Benthic Fauna near Fukushima.

Marine animals, seawater, and sediment near Fukushima, Japan have become contaminated with 134Cs and 137Cs released in March 2011 from the damaged Fukushima Dai-ichi nuclear power plant. Radiocesium concentrations in some benthic fauna declined more slowly than in pelagic fish in the same region. We tested the hypothesis that benthic fish remained more contaminated due to the bioavailability of radiocesium in sediments. Laboratory experiments demonstrated that the assimilation efficiency of 137Cs was 16% in polychaetes ingesting Fukushima sediment, up to 55% in crabs ingesting polychaetes, and about 80% in fish ingesting worms. In addition, all animals acquired Cs directly from the aqueous phase, but this accounted for only 1.2-2.5% of their total body burden. Thus, diet accounted for nearly all of the total body burden of Cs in these animals. Rate constants of Cs loss from animal tissues were 20% d-1 for polychaetes, 10% d-1 for crabs, and 6% d-1 for fish after acquisition of Cs from water; rate constants following dietary uptake were 45% d-1, 14% d-1, and 5% d-1 for polychaetes, crabs, and fish, respectively. A bioaccumulation model indicated that the transfer factors of Cs from sediments and the trophic transfer factors from worms to predators were about 1. Overall, sediment-bound Cs is sufficiently bioavailable to deposit-feeding polychaetes, and macrofauna assimilate Cs from these polychaetes to account for >90% of their body burden. This helps to explain the longer retention of Cs in bottom-dwelling fish near Fukushima.